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We review the taxonomic identities of museum specimens of three bat species previously reported from Bolivia. We comment on some erroneously reported taxa, or taxa either not represented by voucher materials or based on insufficient data (including acoustic detections) to verify their taxonomic affinities. As result of this review, the list of bat species known to occur in Bolivia is updated to eight families and 133 species, unlike the nine families and 146 species of previous lists. Some recommendations for future research and a brief historical revision of bat inventories in the country are included.

Much recent research has focused on establishing the thermodynamic cost of quantum operations acting on single input states. However, information processing, quantum or classical, relies on channels transforming multiple input states to different corresponding outputs. In Ref. [1] the existence of a bound on the work extraction for multiple inputs was proven. However, no specifics were provided for how optimal multipurpose operations may be constructed, and no upper limit on the dissipated work was given. For the insightful case of qubits, we here give explicit protocols to implement work extraction on multiple states. We first prove conditions on the feasibility of carrying out such transformations at all. Furthermore, we quantify the achievable work extraction, and find that there is a dramatic penalty for multipurpose operations. Our results will be relevant for the growing field of quantum technologies in the thermodynamic assessment of all quantum information processing tasks.

Developing a multidisciplinary research aimed to promote the Safe Ageing of elderly citizens in Alentejo region. Intend to understand and prevent falls and violence in institutionalised and non-institutionalised seniors, in order to decrease economic and financial costs related to falls, injuries and violence.

Participating longevity-linked life annuities (PLLA) in which benefits are updated periodically based on the observed survival experience of a given underlying population and the performance of the investment portfolio are an alternative insurance product offering consumers individual longevity risk protection and the chance to profit from the upside potential of financial market developments. This paper builds on previous research on the design and pricing of PLLAs by considering a Bayesian Model Ensemble of single population generalised age-period-cohort stochastic mortality models in which individual forecasts are weighted by their posterior model probabilities. For the valuation, we adopt a longevity option decomposition approach with risk-neutral simulation and investigate the sensitivity of results to changes in the asset allocation by considering a more aggressive lifecycle strategy. We calibrate models using Taiwanese (mortality, yield curve and stock market) data from 1980 to 2019. The empirical results provide significant valuation and policy insights for the provision of a cost effective and efficient risk pooling mechanism that addresses the individual uncertainty of death, while providing appropriate retirement income and longevity protection.

Self-oscillations are the result of an efficient mechanism generating periodic motion from a constant power source. In quantum devices, these oscillations may arise due to the interaction between single electron dynamics and mechanical motion. Due to the complexity of this mechanism, these self-oscillations may irrupt, vanish, or exhibit a bistable behavior causing hysteresis cycles. We observe these hysteresis cycles and characterize the stability of different regimes in single and double quantum dot configurations. In particular cases, we find these oscillations stable for over 20 seconds, many orders of magnitude above electronic and mechanical characteristic timescales, revealing the robustness of the mechanism at play. The experimental results are reproduced by our theoretical model that provides a complete understanding of bistability in nanoelectromechanical devices., Comment: 11 pages, 10 figures, includes the complete paper and the Supplemental Material

In the last decades, the Chilean educational system is carrying on a process of increasing reforms, beginning with the instauration of a voucher system. Since the implementation of this scheme, however, researchers have pointed out the low academic efficacy and remarkable problem of equity that have developed from this intended reform. After the resulting social discontent, education became an undeniable priority in the national debate; consequently, a significant adjustment to the system was enacted in 2008. Existing scholarly work points to the need for expanding the study of school effectiveness to include a wider notion of context. Theoretically, part of the existing research isolates school performance from its wider sociocultural context, which can be defined as the policy environment and socioeconomic composition of the school. Both of these definitions of context have been avoided or reduced. Although the current effectiveness research emphasises school processes as a way to centralise the idea that school can make a difference, it nevertheless remains acritical with regard to specific policy ideological assumptions and their implications on the notion of effectiveness and the real power of the school to take part in social change. The purpose of this research is to broaden the study of school effectiveness within a long-lasting market oriented system. Using a mixed method research design, the data is collected and analysed through quantitative and qualitative approaches. Deploying multilevel analysis (HLM), the study analyses the presence and impact of the socioeconomic composition of school related to the effectiveness and equity of mathematics academic distribution in 4th grade students at a national level. Aiming to decode the impact of recent policy accountability, the qualitative approach interviews principals and teachers, thereby examining practices for effectiveness and the impact of accountability on the teachers' sense of professionalisation. Nvivo software is used to initiate a grounded theory explanation of the sensemaking of principals and teachers in three socioeconomic disadvantaged school cases. The study concludes that the level of socioeconomic composition of a school impacts more strongly than the family socioeconomic composition, constituting a double disadvantage for vulnerable students. Disadvantaged students attending disadvantaged schools are doubly affected by socioeconomic segregation. These contextual variables affect the effectiveness of schools, resulting in school comparisons that are unfair and misleading. Public schools appear to perform better than private schools when contextual variables are taken into account; however, the existing public policy of school classification does not include multilevel analysis or the type of contextual variables incorporated in this research. Another important conclusion of this study is that the policy of accountability erodes teacher professionalisation and encourages an authoritarian type of leadership. The practice of emphasising specific subjects and the idea of equating student learning with results on standardised evaluations affect the pedagogical practices of teachers, limiting their process to undertaking a series of routine actions for test preparation. Moreover, the urgency toward achieving good test results encourage schools to focus their practices on accomplishing these results, and not on the process of learning. A successful approach to effectiveness within the accountability system seems to be related to highly organised schools with a top-down type of leadership. Disadvantaged schools with a high sense of teacher professionalism and with democratic and flexible school organisation appear to be in opposition to the accountability policy. These findings have significant implications for the operation of a market oriented system. The market oriented system operating in Chile affects the distribution of student opportunities based on their socioeconomic background. The existing school segregation impacts both the operations inside the school and the purpose of the system that is intended to equalise and develop opportunities for students, thereby making school a social institution that can have a positive effect on the lives of pupils and staff. Persisting in a view of the market as a social regulator of effectiveness is not supported by empirical evidence; instead, this view shifts responsibility to the schools and encourages them to compete with each other as a logic of productivity, which affects how schools respond to students who are most in need of their care. Reducing the objectives of education to performativity leads to an impoverishing of the educational experience of students, and a diminishing sense of professionalism of staff. The notion of educational quality requires broadening to include a democratic experience of knowledge construction.

Grado en Derecho

Los materiales liberados durante el proceso de intemperización del suelo pueden ser removidos del sistema en el proceso de drenaje del agua o pueden reaccionar en el sistema para formar una variedad de productos cristalinos o amorfos. Los productos de reacción que se observan comúnmente, son los minerales de arcilla y los óxidos e hidróxidos de aluminio y hierro. La caracterización de estos materiales es de vital importancia porque son ellos quienes reflejan de mejor manera los efectos a largo plazo del entorno químico y de los mecanismos de drenaje del suelo. Además, estos materiales tienen marcada influencia en muchas propiedades del suelo. En el presente trabajo se reportan los resultados de la caracterización mineralógica y elemental de una muestra de suelo proveniente del Fundo Vivero Frutícola Motupe, perteneciente a la Facultad de Agronomía de la Universidad Nacional Pedro Ruiz Gallo de Lambayeque, para lo cual se hace uso de las técnicas de Fluorescencia de rayos X (FRX), difractometría de rayos X (DRX) y espectroscopia Mössbauer por transmisión (EMT). Se incluye además los procedimientos de análisis de rutina como pH, conductividad eléctrica, porcentaje de carbonatos y bicarbonatos. Se analizó la muestra en bruto Mo06. DRX permitió la identificación de Cuarzo, Illita, Ortoclasa y Albita en la muestra en bruto. EMT permitió identificar, en la muestra en bruto, un sexteto adjudicado a la Hematita, un doblete central que podría ser adjudicado a un óxido de hierro en estado superparamagnético y dos dobletes adjudicados a la Illita. La composición química fue determinada haciendo uso de FRX. Se detectaron Hierro y Silicio como elementos mayoritarios y Azufre, Cloro, Potasio, Calcio, Titanio, Vanadio, Cromo, Manganeso, Níquel, Cobre, Zinc, Rubidio, Estroncio y Zirconio como elementos minoritarios. Palabras clave.-Difractometría de rayos X, Espectroscopia Mössbauer, Fluorescencia de rayos X, Súper paramagnetismo. ABSTRACTThe products derived from the weathering process of soils can be removed from this system by the process of water drainage or they can react in this system by forming a variety of crystall or amorphous products. The reaction products that are most commonly observed are the clay minerals, the oxides and hydroxides iron and aluminum. The characterization of these materials is of vital importance because they reflect at its best the long term effects of the chemical environment and draining mechanisms of soils. Moreover, they have a marked influence on many soil properties. This paper reports the results of the elemental and mineralogical characterization of a soil sample from the Motupe orchard and nursery farm that belongs to the Pedro Ruiz Gallo National University, Lambayeque, using X-ray Fluorescence (XRF), X-ray Diffraction (XRD) and Transmission Mössbauer Spectroscopy (EMT) techniques were used. Other routine soil analysis were also applied such as texture, pH, electrical conductivity and percent content of carbonates and bicarbonates. The Mo06 sample bulk was tested. By XRD was identified. Quartz, Illite, Orthoclase and Albite. In the bulk sample by TMS was identified a sextet attributed to Hematite, a central doublet that could be assigned to an iron oxide in the super paramagnetic state and two doublets assigned to the Illite. The chemical composition, for elements with atomic number higher than 13, was determines by XRF. Iron and silicon were determine to be the major components, and Sulfur, Chlorine, Potassium, Calcium, Titanium, Vanadium, Chrome, Manganese, Nickl, Copper, Zinc, Rubidium, Strontium and Zirconium as minor components. Number larger than 13, and Zinc, Rubidium, Strontium and Zirconium as minor components. Keywords.- X ray diffractometry, Mössbauer spectroscopy, X-ray fluorescence, Super paramagnetic.

Akodon spegazzinii Thomas, 1897 Akodon spegazzinii Thomas, 1897. Annals and Magazine of Natural History, 6(20): 216. Akodon tucumanensis J. A. Allen, 1901. Bulletin of the American Museum of Natural History, 14: 410. Akodon alterus Thomas, 1919. Annals and Magazine of Natural History, 9(3): 496. Akodon leucolimnaeus Cabrera, 1926. Revista Chilena de Historia Natural, 30:320. Holotype: B.M. 97.5.5.14. Type locality: Lower Cachi (Thomas 1897). Probably Thomas referred to the lower course of the R��o Cachi which passes through the town of Cachi, close to the junction with the R��o Calchaqu��. The town is situated in the Deparment of Cachi, in central Salta Province (25�� 07`11.93``S, 66�� 09`47.00``W, 2341 m). Description: Because of the terse description of the species (Thomas 1897) and the paucity of specimens available to later workers (Myers et al. 1990; D��az 1999), here we offer a more detailed description of A. spegazzinii based on topotypic specimens but including also material coming from the known range of the species. General coloration remarkably variable, with individuals ochraceous brown, ruddy brown, fulvous brown, and buffy brown, and darker or paler depending on individuals and populations. Dorsal coloration uniform from head to rump and with more or less spattered black or dark brown hairs. The yellow eye ring are always present but its development is variable. Ears of same color as dorsum. Flanks with the same coloration as dorsum but some clearer. The venter is buffy, ruddy gray or ochraceous gray and contrast lightly with the dorsum. The chin is covered by a few isolated white hairs that do not form a conspicuous patch. Inguinal region of some individuals with a more intensive hue. Both fore and hind feet covered with bicolored hairs and whitish, buffy or greyish in appearance. Claws covered with tufts of hairs greyish brown at the base and tipped white. Tail conspicuously bicolored, dorsally brown or blackish brown and ventrally whitish or buffy, more or less furred depending on population. Skull of intermediate size for the boliviensis group and characterized by a well-developed rostrum, relatively narrow zygomatic notches, and lightly swollen frontal sinuses. Interorbital region hourglass shaped, with rounded or slightly squared margins and without overhanging borders. Zygomatic arches not specially flared. The braincase is relatively inflated, but some variation exists among individuals. Temporal and lambdoid crests relatively well developed, mainly in old individuals. Dorsal profile of the cranium relatively arched, especially in young specimens. Zygomatic plate breadth generally intermediate in size but highly variable among individuals. The anterior margin is straight or slightly concave with its dorsal root gently sloping backward. Hamular process generally slender and expanded in its distal end. Posterior ascending process of alisphenoid reaches or surpasses the squamoso-alisphenoid groove. Postglenoid foramen and subsquamosal fenestra are developed, and the ratio between them is highly variable. Incisive foramina relatively long, extended in some specimens to the anterior border of hypocone of M1. Mesopterygoid fossa of intermediate breadth for the group, with the anterior margin slightly rounded or squared and with the lateral borders straight and slightly divergent backward. The medial process of posterior palate can be present but never is well developed. Posteropalatal pits generally tiny and situated at the same level or slightly backward with respect to the anterior margin of mesopterygoid fossa. Parapterygoid fossae of the same breadth or slightly broader than mesopterygoid fossa, relatively shallow, with lateral margins straight or slightly convex, diverging backwards. Tympanic bullae not especially developed with Eustachian tubes generally broad and short. Mandibular ramus delicate. Anterior end of maseteric crest situated just behind the level of the anterior border of M1. The development and position of the capsular projection is variable: in general, it is conspicuous and situated slightly behind the posterior border of the coronoid process. This process is delicate and extends just above the condyloid process. The condyle extends behind the posterior margin of angular process. Upper incisors orthodont, with yellowish orange enamel. Molars with crested crown. M1 with well developed procingulum and anteromedian flexus. The anteroloph is conspicuous, the mesoloph is short and the enteroloph is very small (sometimes missing). A small parastyle can be observed in some specimens. The posteroflexus is poorly developed. M2 with a remnant of anteroloph, which determines a relatively well-developed paraflexus. A weak mesoloph and a very shallow protoflexus and posteroflexus also characterize this molar. M3 with paraflexus and metaflexus clearly visible in most of the examined individuals (excepting very old individuals), sometimes as enamel islands. This molar is not ���8��� shape because the hypoflexus is vestigial and disappears at a very young age. The m1 shows a conspicuous procingulum, well-developed anteromedian flexid and anterolabial cingulum, a tiny ectostylid, and a vestigial mesolophid. The m2 shows a very shallow protoflexid; a tiny ectolophid and a vestigial mesolophid are observable in a few specimens. The m3 presents a remnant of protoflexid, a mesoflexid and a transverse and conspicuous hypoflexid, making it ���S��� shaped. This molar has no trace of posteroflexid. Akodon spegazzinii has 13-14 thoracic ribs; the vertebral column includes 13-14 thoracic, 7-8 lumbar, and 23-26 caudal vertebrae (n = 19). Karyotype: 2n = 40, FN = 40, based on four specimens from Catamarca and one from Tucum��n (Barquez et al. 1980; Myers et al. 1990). Variation: There is considerable variation in external characters among the different populations of A. spegazzinii. Most of these differences probably reflect the different environments from where they were trapped. Populations from humid and low altitude areas are darker, with predominance of black guard hairs. This condition is extreme in populations living in Yungas forest. On the other hand, those populations from open and semiarid environments, such as the Monte desert (e.g. Cachi, type locality of A. spegazzinii) and Puna, are remarkably paler. Moreover, specimens from high altitude localities have fur, ears and tails more densely covered and with longer hairs. Variation within populations includes different color patterns, with ruddy, drabby and dark brown animals. These variations were observable even in mice trapped in the same traplines, in some cases related to reproductive condition or the age of individuals. For example, lactating females were particularly reddish in hue and young individuals darker. Morphometric differences are also conspicuous, even in individuals of the same age class. Some qualitative characters also show some variability. The zygomatic plate is highly variable, with both straight or concave anterior borders more or less sloping backwards. The zygomatic notches can be more or less narrow and shallow. The mesopterygoid fossa can be more or less broad and its anterior border rounded or squared. Our genetic sample includes 17 specimens of A. spegazzinii collected at 10 localities form Catamarca, Salta, and Tucuman provinces. This sample has high haplotypic diversity with 16 haplotypes recovered. However, all are similar as average pairwise comparison among them is 1.2%, and geographic structure is nonexistent. Comparisons: For comparisons between A. spegazzinii and A. boliviensis or A. caenosus please see those accounts. Below we compare it with the remaining species of Akodon present in Yungas of Northwestern Argentina. Jayat et al. (2007a) made detailed comparisons between A. spegazzinii and A. sylvanus. The most relevant differences included general size, with A. sylvanus slightly larger for all the morphometric characters analyzed (Tables 1 and 2). The PCA (Fig. 2) shows some overlap for this species but the DA was very efficient, with only four of 139 individuals not reciprocally well classified. Akodon sylvanus presents also relatively less developed zygomatic notches, more inflated frontal sinuses, broader mesopterygoid fossa, broader and deeper paraterygoid fossa, more developed foramen oval, and conspicuously larger foramen magnum. The general coloration of A. sylvanus is included in the observed variation for the different populations of A. spegazzinii. Notwithstanding, the latter has a more conspicuous eye ring and white spot on the chin. The average percentage of genetic divergence between these species is 4.9% (Table 12). Akodon budini is substantially larger and shows very distinguishable craniodental characteristics. It has a very broad braincase and mesopterygoid fossa, elongated rostrum and relatively narrow and shallow zygomatic notches. The mandible is also distinguishable by the short masseteric crest and lightly developed capsular projection. Moreover, the conspicuous hypsodont molars of A. budini uniquely characterize this species. Akodon simulator and A. spegazzinii are sympatric in parts of their ranges; however, these species are easily differentiable by the larger size of A. simulator and, more importantly, several characteristics of the skin. For example, A. simulator has a more greyish general coloration, more contrast between dorsum and venter, and presents a conspicuous white spot on chin and throat. The skull of A. simulator is more robust, with more divergent and squared interorbital region and broader mesopteryogoid fossa. Furthermore, this species has more proodont incisors. The differences between A. spegazzinii and the new species are considered in detail below. Distribution: A. spegazzinii occurs in southern and central areas of northwestern Argentina, from 24�� 27��� S in central Salta to 28�� 47��� S in southern Catamarca, from 400 to about 3500 m. A single specimen (CNP 1897) is known from southern Mendoza province (Laguna LLancanelo, 1335 m, Malarg��e Department, 35�� 45��� S, 69�� 08��� W); this locality, the first reported for Mendoza province, extends the known distribution of A. spegazzinii 850 km to the south. Records from La Rioja province (Thomas 1920b as A. alterus), corresponding to specimens not examined by us, need confirmation (Fig. 9). Habitat: A. spegazzinii occurs in all altitudinal belts of the Yungas forest (even ecotonal areas with lowland thorn woodlands of Chaco), Monte de Sierras y Bolsones, Puna and Altos Andes. Thus, the species inhabits forests, woodlands and grasslands. In dry areas, such as the Monte desert and Puna, it is only found in grassy zones along streams and rivers. Akodon spegazzinii is especially abundant in cloud grasslands in the upper altitudinal belts of Yungas, where it constitutes the dominant sigmodontine species (Fig. 10). Natural History: Reproduction appears to occur yearlong, with a clear peak between November and April. Most of the individuals were molting in fall and winter (April to August). As it can be expected from the general ubiquity of the species, Akodon spegazzinii coexists with a number of sigmodontine species in the region of interest. In high altitudinal localities, above 3000 m, it has been registered alongside Calomys lepidus (Thomas), Eligmodontia sp., Phyllotis xanthopygus, Reithrodon auritus (G. Fischer) and Neotomys ebriosus Thomas. In cloud grasslands it was caught with Necromys lactens, N. lasiurus and Phyllotis osilae. In forested areas of Yungas A. spegazzinii coexists with Abrothrix illutea, Oligoryzomys sp., Oxymycterus paramensis, O. wayku and Phyllotis anitae. In ecotonal environments of Yungas and Chaco, A. spegazzinii was caugth with Calomys fecundus Thomas, Graomys centralis and Necromys sp. Other species broadly distributted in the region, such as Akodon caenosus, Akodon simulator, Oligoryzomys cf. O. flavescens, Calomys musculinus and Andinomys edax, have also been registered in sympatry with A. spegazzinii. Comments: Myers et al. (1990) viewed spegazzinii as a valid species and considered tucumanensis (type locality Tucum��n, 450 m) as a subspecies. Moreover, Akodon alterus (from Otro Cerro, 3000 m) was considered ���properly allied��� to these forms. Blaustein et al. (1992) studied the status of A. alterus and A. tucumanensis and found weak morphologic and morphometric differences and identical cytogenetic characteristics in the studied populations. Notwithstanding, Mares et al. (1997) listed alterus and tucumanensis as valid species mainly based on their different ecological associations (see also Capllonch et al. 1997; D��az et al. 1997; D��az 1999). In the last ten years the treatment of alterus continued to be confused, alternatively considered as a valid species (D��az 1999; D��az & Barquez 2007), as a subspecies of A. spegazzinii (D��az et al. 2000) or simply as a synonym of this last form (Musser & Carleton 2005; Pardi��as et al. 2006). On the other hand, A. tucumanensis has been recently considered as a synonym of A. spegazzinii (Musser & Carleton 2005), as a subspecies of this last form (Pardi��as et al. 2006) or as a valid species (D��az & Barquez 2007). Cabrera (1926) described A. leucolimnaeus based on two specimens of Laguna Blanca and one from Salar de Antofalla, Catamarca Province. Gyldenstolpe (1932) suggested that this form be included in the genus Necromys Ameghino. For many years this nominal form was considered as a synonym of Necromys lactens Thomas (Cabrera 1961; Reig 1987; Musser & Carleton 1993; Mares et al. 1997) but Galliari et al. (1996) regarded it a valid species, allied to the A. boliviensis group. This view was maintained by Musser & Carleton (2005) and Pardi��as et al. (2006) but its status was considered provisional. Here we offer the first detailed description for A. spegazzinii (see above). We formally tested the taxonomic status of A. alterus and A. leucolimnaeus and established their conspecificity with respect to A. spegazzinii. Moreover, we corroborated the conspecificity of tucumanesis and A. spegazzinii, as suggested by Myers et al. (1990). No clear or constant morphologic differences in skull characters among the specimens coming from Cachi, Laguna Blanca, vicinities of Otro Cerro, and Yungas forest in Tucum��n were found (Fig. 11). Moreover, haplotypes recovered from specimens collected near the type locality of alterus, and assignable to this form, and at the type localities of leucolimnaeus and tucumanensis form part of the spegazzinii clade (Fig. 1). Therefore, the combination of genealogical, genetic (Table 12), morphologic, and morphometric (Tables 5- 8) evidence prompt us to suggest that A. alterus, A. leucolimnaeus , and A. tucumanensis are conspecific with A. spegazzinii. We submit that the lack of large samples, coupled with the geographic and ecotypic variation in pelage described above, misinformed the original authorities of these nominal forms. Specimens from Tucum��n (type locality of tucumanensis) have very dark tones, almost black in some exemplars, which is typical of humid cloud forest dwellers. On the contrary, specimens from Laguna Blanca, in puna environments, have very clear tones, with buffy brown coloration. Individuals coming from Cachi and Otro Cerro are intermediate in coloration although they also differ among them. Cachi presents the typical environmental features of Monte de Sierras y Bolsones, with arid to semi-arid conditions, while Otro Cerro is dominated by relatively humid grasslands communities that are characteristic of the upper belt of Yungas in transition with high Andean environments (Fig. 10)., Published as part of J. Pablo Jayat, Pablo E. Ortiz, Jorge Salazar-Bravo, Ulyses F. J. Pardi��as & Guillermo D'El��a, 2010, The Akodon boliviensis species group (Rodentia: Cricetidae: Sigmodontinae) in Argentina: species limits and distribution, with the description of a new entity, pp. 1-61 in Zootaxa 2409 on pages 28-32, DOI: 10.5281/zenodo.293461, {"references":["Thomas, O. (1897) On some small mammals from Salta, N. Argentina. Annals and Magazine of Natural History, (6) 20, 214 - 218.","Cabrera, A. (1926) Dos roedores nuevos de las montanas de Catamarca. Revista Chilena de Historia Natural, 30, 319 - 321.","Myers, P., Patton, J. L. & Smith, M. F. (1990) A review of the boliviensis group of Akodon (Muridae: Sigmodontinae) with emphasis on Peru and Bolivia. Miscellaneous Publications of the Museum of Zoology, University of Michigan, 177, 1 - 89.","Diaz, M. M. (1999) Mamiferos de la Provincia de Jujuy: Sistematica, distribucion y ecologia. Unpublished D. Phil. Thesis, Universidad Nacional de Tucuman, Argentina, 640 pp.","Barquez, R. M., Williams, D. F., Mares, M. A. & Genoways, H. H. (1980) Karyology and morphometrics of three species of Akodon (Mammalia: Muridae) from northwestern Argentina. Annals of Carnegie Museum, 49, 379 - 403.","Jayat, J. P., Ortiz, P. E., Pardinas, U. F. J. & D'Elia, G. (2007 a) Redescripcion y posicion filogenetica del raton selvatico (Akodon sylvanus: Rodentia: Cricetidae). Mastozoologia Neotropical, 14, 201 - 225.","Thomas, O. (1920 b) On small Mammals from the Famatina Chain, North-western Rioja. Annals and Magazine of Natural History, Series, 9 (6), 417 - 422.","Blaustein, S. A., Liascovich, R. C., Apfelbaum, L. I., Daleffe, L. Barquez, R. M. & Reig, O. A. (1992) Correlates of systematic differentiation between two closely related allopatric populations of the Akodon boliviensis group from NW Argentina (Rodentia, Cricetidae). Zeitschrift fur Saugetierkunde, 57, 1 - 13.","Diaz, M. M., Braun, J. K., Mares, M. A. & Barquez, R. M. (1997) Key of Mammals of Salta Province, Argentina. Occasional Papers of the Oklahoma Museum of Natural History, 2, 1 - 10.","Capllonch, P., Autino, A., Diaz, M. M., Barquez, R. M. & Goytia, M. (1997) Los mamiferos del Parque Biologico Sierra de San Javier, Tucuman, Argentina: observaciones sobre su sistematica y distribucion. Mastozoologia Neotropical, 4, 49 - 71.","Diaz, M. M. & Barquez, R. M. (2007) The Wild Mammals of Jujuy Province, Argentina: Systematics and Distribution. In: Kelt, D. A., Lessa, E. P., Salazar-Bravo, J. & Patton, J. L. (Eds.), The Quintessential Naturalist: Honoring the Life and Legacy of Oliver P. Pearson. University of California Publications in Zoology 134, pp. 417 - 578.","Diaz, M. M., Braun, J. K., Mares, M. A. & Barquez, R. M. (2000) An update of the taxonomy, systematics, and distribution of the mammals of Salta province, Argentina. Occasional Papers of the Oklahoma Museum of Natural History, 10, 1 - 52.","Musser, G. M. & Carleton, M. D. (2005) Superfamily Muroidea .. In: Wilson, D. E. & Reeder, D. M. (Eds.) Mammal species of the world: A taxonomic and geographic reference. Third ed. Baltimore: John Hopkins University Press, pp. 894 - 1531.","Jayat, J. P., Ortiz, P. E., Teta, P., Pardinas, U. F. J. & D'Elia, G. (2006) Nuevas localidades argentinas para algunos roedores sigmodontinos (Rodentia: Cricetidae). Mastozoologia Neotropical, 13, 51 - 67.","Gyldenstolpe, N. (1932) A manual of Neotropical sigmodont rodents. Kunglia Svenska Vetenskapsakademiens Handlingar, Stockholm, 11, 164 pp.","Cabrera, A. (1961) Catalogo de los mamiferos de America del Sur. Parte II. Revista del Museo Argentino de Ciencias Naturales \" Bernardino Rivadavia \", Zoologia, 4 (2), 309 - 732.","Reig, O. A. (1987) An assessment of the systematics and evolution of the Akodontini, with the description of new fossil species of Akodon (Cricetidae: Sigmodontinae). Pp. 347 - 399 in Studies in Neotropical mammalogy. Essays in honor of Philips Hershkovitz (Patton, B. D. & Timm, R. M., eds.). Fieldiana, Zoology, new series, 39, 1 - 506.","Musser, G. M. & Carleton, M. D. (1993) Familia Muridae. In: Wilson, D. E. & Reeder, D. M. (Eds.), Mammals species of the world: a taxonomic and geographic reference. Washington: Smithsonian Institution Press, pp. 501 - 756.","Galliari, C. A., Pardinas, U. F. J. & Goin, F. J. (1996) Lista comentada de los mamiferos argentinos. Mastozoologia Neotropical, 3, 39 - 61."]}

Akodon boliviensis Meyen, 1833 Akodon boliviense Meyen, 1833. Verhandlungen der Kaiserlichen Leopoldinisch-Carolinischen Akademie der Naturforscher, 16(2):600, pl. 43, fig. 1. Holotype: no holotype was designated by Meyen. Type locality: ���Auf der Hochebene von Hochperu, in dem Indianer-dorfe Pichu-pichun, auf einer H��he von 14,000 fuss gefangen.��� Pichu-Pich��n, 14,000 ft., Chucuito Province, Puno Department, Peru (as clarified by Myers et al. 1990). Description: Detailed morphological description in Myers et al. (1990). The specimens of northwestern Argentina follow, in general, this description and can be distinguished from the remaining species present in this region by the following combination of characters. Dorsal fur soft and somewhat dense, with dorsal coloration uniform pale brown with an olivaceous tinge and lightly streaked with black hairs. Yellow eyerings well defined. Ears of the same color as dorsum and densely covered with hairs. Coloration of sides similar to or somewhat lighter than dorsum. Venter buffy, clearly contrasting with dorsum. Chin with a small patch of completely white hairs. Inguinal region almost rufous in some individuals. Fore and hind feet of the same general coloration than the venter, with bicolored hairs, brown on base and whitish or pale buff on tip. Tail heavily covered with hairs and bicolored, dark brown dorsally and whitish or pale buffy ventrally. Skull with rostrum short and relatively broad. Zygomatic notches proportionally broad and deep. Frontal sinuses slightly swollen. Interorbital region slightly divergent with margins in posterior half something squared in adult specimens. Zygomatic arches relatively well developed. Braincase inflated with temporal and lambdoidal crests relatively well developed. Zygomatic plate with anterior margin flat or slightly concave, oriented vertically or slopes gently backward from bottom to top. Most of examined specimens shows a posterior ascending process of alisphenoid projected at least to the squamoso-alisphenoid groove. Incisive foramina extending to the level of the hypoflexus of M1 or surpassed it. Mesopterygoid fossa narrow with straight borders and sides either parallel or gradually diverging posteriorly, and anterior margin rounded or squared. Parapterygoid fossae broader than mesopterygoid fossa, diverging backward and with straight to slightly convex lateral margins. Mandibular ramus delicate with masseteric crest extending slightly behind of the anterior border of m1, although in some individuals it only reaches the level of protoflexid. Capsular projection well developed and generally situated below the sigmoid notch. Upper incisors generally orthodont. The M1 with procingulum and anteromedian flexus well developed. The anteroloph and mesoloph are always present, the enteroloph is tiny and present only in some specimens. The M2 shows a well developed mesoloph and the M3 is large and complex, with well developed metaflexus and hypoflexus making it distinctively ���8���-shaped in most specimens. The m1 presents a well developed procingulum and a penetrating anteromedian flexid. Protostylid and ectostylid are always presents but the second is poorly defined in some individuals. A small mesolophid-mesostylid is present in a few specimens. In m2 most of the examined specimens have an ectostylid, and a mesolophid-mesostylid is present only in a few individuals but always vestigial (the only young specimen and two adults individuals). The m3 is proportionally large (nearly a half of m2), showing a poorly developed anterior cingulid in most specimens. Karyotype: 2n = 40, FN = 40-42, from Puno and Tacna Departments, Peru (Gardner & Patton, 1976; Myers et al., 1990). Variation: In the few known specimens from northwestern Argentina most variation is age-dependent. Pelage color of young specimens is slightly darker than that of adults. Young individuals also present a shorter and more delicate rostrum, narrower zygomatic notch, less swollen frontal sinuses, broader interorbital region and more inflated braincase. Moreover, the incisive foramina and the mesopterygoid fossa are narrower and the parapterygoid fossae not as deeply excavated. Some variable characters unrelated with age include the general coloration, with some individuals more richly colored; eye ring, development of the hamular process of the squamosal (i.e., tympanic hook in Myers et al., 1990) and the shape of anterior margin of the mesopterygoid fossa. Representatives of this species in northwestern Argentina are morphometricly indistinguishable from those of Peru and Bolivia although they are slightly smaller in some measurements (e.g. CIL, RL) and slightly larger in others (e.g. IOC, IFL, RW 2). Nine specimens coming from Abra de Cienaga Negra and one from Azul Cuesta show subtle morphologic and morphometric differences respect to the specimens from Rodeo Pampa and Pampa Verde (whose haplotypes were more closely related to that of a Peruvian specimen MVZ 171607). These specimens are more richly colored, have a broader interorbital constriction (IOC) and rostral width (RW 2), and a thiner zygomatic plate (ZP). Comparisons: Akodon boliviensis is a medium sized species within the boliviensis group and is, on average, larger than A. caenosus for most of the analyzed measurements (Table 1). Nevertheless, only braincase breadth (BB), mid rostral width (RW 2) and molars series (MTRL and MdTRL) were statistically different according to the N HSD test (Table 2). The PCA analysis indicates some overlap between these species (Fig 2) but the DA misclassified only one of the specimens of A. boliviensis as A. caenosus. In general, the coloration of A. boliviensis is somewhat paler than A. caenosus and the ears are more densely furred. Cranial traits such as a more developed zygomatic notches and a proportionally narrower interobital region distinguish A. boliviensis. Contrary to that observed in A. boliviensis, only in few studied specimens of A. caenosus in northwestern Argentina the posterior ascending process of the alisphenoid extend to the squamoso-alisphenoid groove. As Myers et al. (1990) recognized, the shape of M3 and the thickness of the hamular process of squamosal also differentiate both species. However, A. caenosus shows a great variability in these traits. Additionally, these species show a relatively high average percentage (7.0%) of genetic divergence (Table 12). The examined skins of Akodon boliviensis are very similar to those of specimens of Akodon spegazzinii from high altitude localities, sharing similar hue and color patterns. However, A. boliviensis is on average smaller than A. spegazzinii for most morphometric measurements (Table 1) with the N HSD test indicating significative differences in seven of these measurements (Table 2). In this sense, A. boliviensis presents a more delicate skull, with shorter rostrum and molar series, narrower braincase, narrower and more shallow zygomatic notches and less flared zygomatic arches. The PCA analysis indicates some overlap (Fig 2) but the DA was efficient in separating these species, with only two misclassified specimens. The genetic distance between these taxa is relatively small (2.8%). The striking morphometric and coloration pattern differences between A. boliviensis and A. sylvanus preclude confusing these species. Akodon boliviensis is conspicuously paler, with a drabby brown color, whereas A. sylvanus is dark brown with a strong olivaceous tinge. The contrast between dorsum and venter is more conspicuous in A. boliviensis. In addition, this species shows a more developed eyering and white spot on the chin. The skull of A. boliviensis is clearly more slender, with a shorter and more delicate rostrum, and narrower braincase, interorbital region and mesopterygoid fossa. The molars in A. boliviensis are smaller and clearly less hypsodont. The morphometric differences between these species are notorious with practically no overlap in PCA and none misclassified specimens in DA (Tables 1, 2 and figure 2). The average percentange of genetic divergence between these species is 4.9 %. The comparison between A. boliviensis and the new species will be addressed under the treatment of the latter. Distribution: In northwestern Argentina A. boliviensis is restricted to northernmost Salta Province, mainly above 2500 m (Jayat et al. 2006). All known records come from the Zenta and Santa Victoria ranges. Thus, it is likely that the species probably reaches adjacent Jujuy province due to the continuity of habitats along these mountain ranges (Fig. 6). Habitat: We captured most specimens in highland grasslands, both in upper forest/humid grassland ecotones as well as in drier grasslands more typical of Andean environments. Most of the collecting localities are characterized by grasslands interspersed with rocky outcrops, although in Pampa Verde (locality 6 on figure 6) the humid grasslands are adjacent to alder (Alnus acuminata) forest along humid ravines. Natural history: Four individuals captured in winter (July and August) were molting with only one of them with reproductive activity signs. All specimens caught in spring (nine specimens collected in November) showed reproductive activity and were molting. Other sigmodontine species registered in northwestern Argentina alongside A. boliviensis include Akodon caenosus, Akodon budini Thomas, Necromys lactens Thomas, N. amoenus Thomas, Oligoryzomys cf. O. flavescens (Waterhouse), Oxymycterus paramensis Thomas, Phyllotis osilae J. A. Allen and P. xanthopygus (Waterhouse). Comments: Cabrera (1961) considered A. spegazzinii and A. tucumanensis as subspecies of A. boliviensis, and A. alterus as a synonym of A. boliviensis tucumanensis, a position followed by many authors through the 1980s (e.g. Apfelbaum & Reig 1989; Barquez et al. 1980; Mares et al. 1981; Ojeda & Mares 1989). In the first revision of these small Andean forms, Myers et al. (1990) defined the Akodon boliviensis group, characterized the morphological and distributional boundaries of A. boliviensis, and considered A. spegazzinii as a valid species (with two subspecies A. s. spegazzinii and A. s. tucumanensis). Jayat et al. (2006) erroneously cited A. boliviensis for Escoipe, in central Salta province. This record was based on one specimen (JPJ 69) whose morphometric characteristics were similar to those of A. boliviensis; however, our molecular studies indicate that this and other small specimens caught in the same locality are referable to A. spegazzinii. D��az (1999) and D��az & Barquez (2007) referred one specimen (MMD 395) from Miyuyoc, at 3700 m, Jujuy province to Akodon alterus. We did not examine this specimen, but based on the latitudinal position and characteristics of the reported locality where the specimen was trapped, we note that it may represent another record of A. boliviensis., Published as part of J. Pablo Jayat, Pablo E. Ortiz, Jorge Salazar-Bravo, Ulyses F. J. Pardi��as & Guillermo D'El��a, 2010, The Akodon boliviensis species group (Rodentia: Cricetidae: Sigmodontinae) in Argentina: species limits and distribution, with the description of a new entity, pp. 1-61 in Zootaxa 2409 on pages 20-23, DOI: 10.5281/zenodo.293461, {"references":["Myers, P., Patton, J. L. & Smith, M. F. (1990) A review of the boliviensis group of Akodon (Muridae: Sigmodontinae) with emphasis on Peru and Bolivia. Miscellaneous Publications of the Museum of Zoology, University of Michigan, 177, 1 - 89.","Gardner, A. L. & Patton, J. L. (1976) Karyotypic variation in oryzomyne rodents (Cricetinae) with comments on chromosomal evolution in the Neotropical cricetine complex. Occasional Papers of the Museum of Zoology, Louisiana State University, 49, 1 - 48.","Jayat, J. P., Ortiz, P. E., Teta, P., Pardinas, U. F. J. & D'Elia, G. (2006) Nuevas localidades argentinas para algunos roedores sigmodontinos (Rodentia: Cricetidae). Mastozoologia Neotropical, 13, 51 - 67.","Cabrera, A. (1961) Catalogo de los mamiferos de America del Sur. Parte II. Revista del Museo Argentino de Ciencias Naturales \" Bernardino Rivadavia \", Zoologia, 4 (2), 309 - 732.","Apfelbaum, L. I. & Reig O. A. (1989) Allozyme genetic distances and evolutionary relationships in species of akodontine rodents (Cricetidae: Sigmodontinae). Biological Journal of the Linnean Society, 38, 257 - 280.","Barquez, R. M., Williams, D. F., Mares, M. A. & Genoways, H. H. (1980) Karyology and morphometrics of three species of Akodon (Mammalia: Muridae) from northwestern Argentina. Annals of Carnegie Museum, 49, 379 - 403.","Mares, M. A, Ojeda, R. A. & Kosco, M. P. (1981) Observation on the distribution and ecology of the mammals of Salta Province, Argentina. Annals of Carnegie Museum, 50, 151 - 206.","Ojeda, R. A. & Mares, M. A. (1989) A Biogeographic analysis of the Mammals of Salta Province, Argentina. Patterns of species assemblage in the Neotropics. Special Publications, The Museum, Texas Tech University, 27, 1 - 66.","Diaz, M. M. (1999) Mamiferos de la Provincia de Jujuy: Sistematica, distribucion y ecologia. Unpublished D. Phil. Thesis, Universidad Nacional de Tucuman, Argentina, 640 pp.","Diaz, M. M. & Barquez, R. M. (2007) The Wild Mammals of Jujuy Province, Argentina: Systematics and Distribution. In: Kelt, D. A., Lessa, E. P., Salazar-Bravo, J. & Patton, J. L. (Eds.), The Quintessential Naturalist: Honoring the Life and Legacy of Oliver P. Pearson. University of California Publications in Zoology 134, pp. 417 - 578."]}

Akodon boliviensis species group The great morphological similarity among species of the A. boliviensis group, as well as high levels of intraspecific variability, has precluded a clear and stable taxonomy for the group and in particular for those forms present in northwestern Argentina. This situation, together with the lack of studies of representative series of specimens, including the holotypes and additional specimens collected at the type localities, resulted in the suggestion, along the years, of different taxanomic scenarios, sometimes quite distinct among themselves. As in previous instances (e.g., Patton et al., 2000), the integration of morphologic and molecular data interpreted in a geographic context has proven usefull to assess species boundaries of a taxonomically confusing group. In this regard, the evidence presented herein indicates the existence of four species of the A. boliviensis group in northwestern Argentina with a new species belonging to this group from central Argentina. The taxonomic status of A. spegazzinii (including alterus, leucolimnaeus, and tucumanensis) with respect to A. boliviensis is the most debatable of the taxonomic decisions we make. Based on a small series of specimens, Myers et al. (1990) had earlier proposed the valid status of this form. In line, much of the available evidence here considered suggests that A. spegazzinii represents a distinct species from A. boliviensis. For example, they form reciprocally monophyletic groups (Fig. 1) that are allopatrically distributed; in addition, they are clearly identifiable in morphometric multivariate space and morphological grounds (see comparison above). Moreover, these species have different karyotypes, including the presence of heteromorphism in the largest autosomal pair and the X chromosome in A. spegazzinii (Gardner & Patton, 1976; Barquez et al., 1980; Myers et al., 1990), and different ecological preferences. Our records indicate disjunct distribution for these forms, with A. boliviensis restricted to high altitudinal grasslands in the extreme north of the region and A. spegazzinii extended over many habitats and large areas in south-central portions of the region. In spite of these differences, the genetic divergence betweem them was the smallest among all species pairs of the A. boliviensis group (Table 12). In addition, some overlap in morphological and morphometric characters was evident. Moreover, we could not evaluate the constancy of these differences because we failed to capture both species in sympatry. So, additional studies are needed in the north of the northwestern Argentinean region and in possible areas of sympatry to test the constancy of the observed differences here reported. The taxonomic status of A. tucumanensis, A. alterus, and A. leucolimnaeus remained controversial despite the pioneering work by Myers et al. (1990). While all these forms were treated as subspecies or allied to A. spegazzinii by some authors (e.g. Myers et al. 1990; D��az et al. 2000; Pardi��as et al. 2006; Jayat et al., 2008a), others considered them as valid species (e.g. Barquez et al., 1991; Mares et al., 1997; D��az, 1999; D��az & Barquez, 2007; but see Galliari et al., 1996 about the status of A. tucumanensis). In spite of the extended usage of the specific epithet alterus in previous works (e.g. Capllonch et al. 1997; D��az et al. 1997; Mares et al. 1997; D��az 1999; D��az & Barquez 2007) none of these references was based on a detailed study of extensive topotypical series nor the use of molecular characters. Blaustein et al. (1992) were the only authors who tested the status of alterus (with respect to tucumanensis). However, they erroneously assumed that specimens from El Infiernillo, Tucum��n, belonged to alterus; then, they did not truly test the taxonomic status of A. alterus. They also failed to separate these specimens from A. tucumanensis from low altitude Yungas forest of Tucum��n. In words of Blaustein et al. (1992, pag. 11) ���... we believe that any conclusion on the taxonomic status of the two forms is untimely.��� The status of A. leucolimnaeus was even more dubious and, until the preliminary observations of Galliari et al. (1996), it was considered as a synonym of Necromys lactens (Cabrera, 1961; Reig, 1978, 1987; Mares et al., 1997). However, Galliari et al. (1996) ranked leucolimnaeus as a valid species of Akodon (see also Musser & Carleton [2005] and Pardi��as et al. [2006]), view that contrasts with our results. All the available evidence indicates that the nominal forms alterus, leucolimnaeus, and tucumanensis must be considered junior synonyms of A. spegazzinii. Haplotypes from specimens coming from the type localities of these fall within the spegazzinii clade (Fig. 1). The genetic divergence among haplotypes of this clade is low (1.2% in average) and we found no clear morphological or morphometric differences among these forms. Most of the observed differences in coloration among populations may relate to the great environmental heterogeneity inhabited by A. spegazzinii (Fig. 10). In the A. boliviensis clade, two haplotypes recovered from specimens from northern Salta were more closely related to the haplotype of a Peruvian specimen (MVZ 171607) than to those of other three Argentinean specimens (Fig. 1). This phylogeographic break, together with some morphological, morphometric and genetic differences between these two groups also suggest the possiblity of unrecognized biological diversity within this group. This scenario is similar to that observed in N. amoenus, another highland inhabitant (D���El��a et al., 2008). Notwithstanding, the studied material of A. boliviensis is scarce and the difference between both clades is moderate (2.1% of average genetic divergence), so we point that further research is needed on this area. Myers et al. (1990) considered A. caenosus as a subspecies of A. lutescens (as A. puer caenosus in that publication). They highlighted subtle morphometric, morphologic, and cytogenetic characteristics that distinguished specimens from northwestern Argentina from those of Peru and Bolivia. Our phylogenetic analyses include haplotypes recovered from Argentinean specimens assignable to caenosus and a Peruvian specimen belonging to lutescens. These haplotypes form a paraphyletic group respect to A. subfuscus (Fig. 1). This topology, if lutescens and subfuscus are not to be considered conspecifics, suggests a specific status for A. caenosus. Moreover, the average genetic distance between the Peruvian haplotype of lutescens (MVZ 171612) and those from northwestern Argentinean specimens of A. caenosus is relatively high (3.5%); the average divergence value among specimens of A. caenosus is much lower (1%). Although, there are not clear morphological and morphometric differences among our material of A. caenosus and the values offered by Myers et al. (1990) for A. lutescens, the alternative position of considering A. subfuscus and A. lutescens conspecific seems less supported. These species differ by a substantially high (5.1%) average genetic distance. Furthermore Myers et al. (1990) detailed several morphological characters that distinguish A. lutescens from A. subfuscus. Although we failed to obtain small specimens of Akodon from the type locality of A. aliquantulus (we studied ca. 100 individuals of Akodon from this locality and its surroundings and more than 390 from Tucum��n province), its diagnosis does not permit us to distinguish the two type specimens from A. caenosus. Moreover, the haplotypes of three small Akodon sequenced from Catamarca and Tucum��n were remarkably similar to haplotypes of A. caenosus topotypes (with average genetic distance lower than 1%). On these bases (see also our Species Account discussion above) we place aliquantulus under the synonymy of A. caenosus. This study corroborated the proposition of Jayat et al. (2007a) of placing A. sylvanus as a valid species of the A. boliviensis group. In the MP analysis A. sylvanus appears as the sister species of A. polopi; in accordance to low support of this clade (JKA. polopi is sister to the A. boliviensis - A. spegazzinii clade. Akodon polopi, the new species here described, is a clearly distinct member of the A. boliviensis group, with several diagnostic characters coming from different sources of evidence; not surprinsingly, it was early mentioned as a possible new subspecies by Elio Massoia or a new species (see Polop, 1989). This species, known only from high altitude grasslands of central Argentina, is the only species of the A. boliviensis group inhabiting the Sierras Grandes range, a medium altitude mountain system isolated (ca., 600 km) from the main Andean chain by low elevation arid and semiarid environments. Data at hand are insufficient to pose a biogeographic scenario accounting for the diversification of A. polopi and the remainder species of the A. boliviensis group. Notwithstanding, Pampa de Achala has been mentioned as a biogeographic refuge and an area of endemism for other taxa (Polop, 1989, and references there). Relationships among species of the Akodon boliviensis group are well resolved and mostly coungrent among analyses. Differences relate to the position of A. polopi and A. sylvanus. The present study, as several previous ones, reaffirms the phylogenetic legitimacy of both the boliviensis group and extends our knowledge of its contents, limits, and geographic ranges of its member species. However, we assert that additional research is still needed before an adequate picture of Andean Akodon can be acquired. In this line, more field work coupled with the study of specimen series housed in research institutions is essential., Published as part of J. Pablo Jayat, Pablo E. Ortiz, Jorge Salazar-Bravo, Ulyses F. J. Pardi��as & Guillermo D'El��a, 2010, The Akodon boliviensis species group (Rodentia: Cricetidae: Sigmodontinae) in Argentina: species limits and distribution, with the description of a new entity, pp. 1-61 in Zootaxa 2409 on pages 43-45, DOI: 10.5281/zenodo.293461, {"references":["Patton, J. L., Da Silva, M. D. F. & Malcom, J. R. (2000) Mammals of the rio Jurua and the evolutionary and ecological diversification of Amazonia. Bulletin of the American Museum of Natural History, 244, 1 - 306. Piantanida, M. J. & Barrantes, G. E. (1998) Growth studies in Akodon dolores (Rodentia: Muridae) in captivity. Acta Theriologica, 43, 185 - 193.","Myers, P., Patton, J. L. & Smith, M. F. (1990) A review of the boliviensis group of Akodon (Muridae: Sigmodontinae) with emphasis on Peru and Bolivia. Miscellaneous Publications of the Museum of Zoology, University of Michigan, 177, 1 - 89.","Gardner, A. L. & Patton, J. L. (1976) Karyotypic variation in oryzomyne rodents (Cricetinae) with comments on chromosomal evolution in the Neotropical cricetine complex. Occasional Papers of the Museum of Zoology, Louisiana State University, 49, 1 - 48.","Barquez, R. M., Williams, D. F., Mares, M. A. & Genoways, H. H. (1980) Karyology and morphometrics of three species of Akodon (Mammalia: Muridae) from northwestern Argentina. Annals of Carnegie Museum, 49, 379 - 403.","Diaz, M. M., Braun, J. K., Mares, M. A. & Barquez, R. M. (2000) An update of the taxonomy, systematics, and distribution of the mammals of Salta province, Argentina. Occasional Papers of the Oklahoma Museum of Natural History, 10, 1 - 52.","Jayat, J. P., Ortiz, P. E., Teta, P., Pardinas, U. F. J. & D'Elia, G. (2006) Nuevas localidades argentinas para algunos roedores sigmodontinos (Rodentia: Cricetidae). Mastozoologia Neotropical, 13, 51 - 67.","Jayat, J. P., Ortiz, P. E. & Miotti, M. D. (2008 a) Distribucion de sigmodontinos (Rodentia: Cricetidae) en pastizales de neblina del noroeste argentino. Acta Zoologica Mexicana, 24, 137 - 177.","Barquez, R. M., Mares, M. A. & Ojeda, R. A. (1991) Mamiferos de Tucuman - Mammals of Tucuman. Oklahoma Museum of Natural History, University of Oklahoma, Norman, 282 pp.","Diaz, M. M., Braun, J. K., Mares, M. A. & Barquez, R. M. (1997) Key of Mammals of Salta Province, Argentina. Occasional Papers of the Oklahoma Museum of Natural History, 2, 1 - 10.","Diaz, M. M. (1999) Mamiferos de la Provincia de Jujuy: Sistematica, distribucion y ecologia. Unpublished D. Phil. Thesis, Universidad Nacional de Tucuman, Argentina, 640 pp.","Diaz, M. M. & Barquez, R. M. (2007) The Wild Mammals of Jujuy Province, Argentina: Systematics and Distribution. In: Kelt, D. A., Lessa, E. P., Salazar-Bravo, J. & Patton, J. L. (Eds.), The Quintessential Naturalist: Honoring the Life and Legacy of Oliver P. Pearson. University of California Publications in Zoology 134, pp. 417 - 578.","Galliari, C. A., Pardinas, U. F. J. & Goin, F. J. (1996) Lista comentada de los mamiferos argentinos. Mastozoologia Neotropical, 3, 39 - 61.","Capllonch, P., Autino, A., Diaz, M. M., Barquez, R. M. & Goytia, M. (1997) Los mamiferos del Parque Biologico Sierra de San Javier, Tucuman, Argentina: observaciones sobre su sistematica y distribucion. Mastozoologia Neotropical, 4, 49 - 71.","Blaustein, S. A., Liascovich, R. C., Apfelbaum, L. I., Daleffe, L. Barquez, R. M. & Reig, O. A. (1992) Correlates of systematic differentiation between two closely related allopatric populations of the Akodon boliviensis group from NW Argentina (Rodentia, Cricetidae). Zeitschrift fur Saugetierkunde, 57, 1 - 13.","Cabrera, A. (1961) Catalogo de los mamiferos de America del Sur. Parte II. Revista del Museo Argentino de Ciencias Naturales \" Bernardino Rivadavia \", Zoologia, 4 (2), 309 - 732.","Musser, G. M. & Carleton, M. D. (2005) Superfamily Muroidea .. In: Wilson, D. E. & Reeder, D. M. (Eds.) Mammal species of the world: A taxonomic and geographic reference. Third ed. Baltimore: John Hopkins University Press, pp. 894 - 1531.","Jayat, J. P., Ortiz, P. E., Pardinas, U. F. J. & D'Elia, G. (2007 a) Redescripcion y posicion filogenetica del raton selvatico (Akodon sylvanus: Rodentia: Cricetidae). Mastozoologia Neotropical, 14, 201 - 225.","Polop, J. (1989) Distribution and ecological observations of wild rodents in Pampa de Achala, Cordoba, Argentina. Studies on Neotropical Fauna and Environment, 24, 53 - 59."]}

Akodon caenosus Thomas, 1918 Akodon diminutus Barquez, D��az and Goytia, 1994. Nomen nudum (see Galliari et al., 1996). Akodon aliquantulus D��az, Barquez, Braun and Mares, 1999. Journal of Mammalogy, 80:788. Holotype: BMNH 18.1.1.38, adult male. Type locality: Le��n, Jujuy, 1500 m (Thomas, 1918). Description: Detailed morphological description in Myers et al. (1990) (as A. puer caenosus). Additional morphological and morphometric data for some populations of northwestern Argentina can be found in Thomas (1918; original description of A. puer caenosus), Barquez et al. (1980) and D��az (1999). Here we summarize the characteristics of populations along the latitudinal and altitudinal gradients of northwestern Argentina. Akodon caenosus is the smallest species of the boliviensis group in northwestern Argentina. Dorsal coloration uniform and highly variable, ochraceous brown with yellowish, rufous, or olivaceous casts. Ears of the same color than the dorsum and with a tuft of hairs in front. Laterals clearer than dorsum and more richly colored in some specimens. Venter paler, whitish gray, buffy gray, yellowish or even ruddy, clearly contrasting with dorsum. Chin with few white hairs that do not form a conspicuous patch. Inguinal region with a more intense tinge than the rest of the venter in some specimens. Fore and hind feet covered with whitish or buffy hairs. Tail strongly bicolored, dorsally blackish-brown and ventrally whitish or buffy, densely or sparsely covered depending on the analyzed populations and individuals. The skull is the smallest among the Akodon species of northwestern Argentina. Rostrum short, with very narrow and shallow zygomatic notches and frontal sinuses not well developed. Interorbital region comparatively broad, with hourglass shaped and with margins rounded or slightly squared. Zygomatic arches not flared, braincase small and inflated, with temporal and lambdoid crests not well developed. Zygomatic plate narrow with anterior border straight or slightly concave and generally slopes gently backward from bottom to top. In most of the studied specimens the posterior ascending process of alisphenoid does not reach the squamoso-alisphenoid groove or only touch their lower margin. Hamular process of squamosal delicate, but in a few individuals it is strongly built. Incisive foramina generally extended to the protocone of M1, but in some individuals its reach the hypoflexus or even further back. Mesopterygoid fossa very narrow, its anterior margin rounded or slightly squared and with lateral margins straight and slightly divergent backward. Parapterygoid fossa generally broader than mesopterygoid, with convex border and slightly divergent backward. Mandibular ramus very delicate. Masseteric crest extends slightly behind the anterior margin of m1. Capsular projection generally poorly developed and situated at the same level or behind the coronoid process. Angular process is less extended backward than the condyle. Upper incisors orthodont or slightly opistodont. The procingulum and anteromedian flexus of M1 are well developed. Anteroloph and mesoloph are always present and in some individuals an enteroloph can be observed. The M2 has a conspicuous mesoloph and the M3 shows great variability. In old individuals it is completely oval shaped but in young ones anteroflexus, metaflexus and hipoflexus are present. The m1 has the procingulum and anteromedian flexid well developed and presents protostylid and ectostylid. In some individuals a remnant of metastylid and mesostylid can be observed. The m2 retains only the labial stylid although some specimens have a very small ectostylid. The m3 presents deep labial and lingual flexids. Some individuals show a small protostylid. Karyotype: 2n = 34, FN = 40, based on six specimens from Le��n, Jujuy, and two from El Cadillal, Tucum��n (Barquez et al., 1980; Vitullo et al., 1986 as A. puer). Variation: We have observed substantial morphological variation for this species. Within the same population, we find pale and dark individuals, some of them with striking rufous tones, particularly lactating females. Among the cranial characters, the development of zygomatic notches, zygomatic plate, and the thickness of hamular process show some variability. We also observed morphometric variations for individuals of the same age and population, with remarkable differences among some of the studied localities. In addition, consistent variation in the coloration pattern with elevation and some geographic variation for some morphometric variables are also apparent. The specimens from high altitude populations are conspicuously paler than those from lower localitites, showing more buffy tinges in the coloration of the fur and more developed eyerings. These populations come from open environments characterized as the ecotone between humid grasslands and semiarid areas (e.g., the Prepuna or impoverished grasslands of high-Andean region). Specimens from central Salta and central Tucum��n provinces are on average smaller than individuals from B��rcena and Reyes, southern Jujuy, near the type locality. Comparisons: Externally this species can be confused with A. boliviensis and young individuals of A. spegazzinii. The differences between A. caenosus and A. boliviensis were described in detail by Myers et al (1990) and are summarized above. In areas of sympatry A. caenosus and A. spegazzinii follow similar variation patterns in coloration through altitudinal gradients. However, many morphometric values and several cranial characters are useful in specimen determination. In 15 of the 20 analyzed morphometric variables, A. caenosus is significantly smaller than A. spegazzinii (Tables 1 and 2). This is also verified by the minimum overlap in the PCA analysis (Fig 2) and the lack of missclasifications in the DA. In addition, Akodon caenosus shows narrower and shallower zygomatic notches, comparatively broader interorbital constriction, temporal and mastoid ridges less developed, narrower mesopterygoid fossa and less hypsodont molars. The average percentage of genetic divergence between these species is the greatest (7.7%) observed for the boliviensis group in northwestern Argentina (Table 12). Akodon caenosus and A. sylvanus represent two extremes in the morphometric variation observed within the boliviensis group in northwestern Argentina (Tables 1 and 2; figure 2). Akodon caenosus is, furthermore, paler than A. sylvanus, showing a more evident contrast between dorsum and venter, and has more developed eyerings. The skull of A. caenosus has a shorter and narrower rostrum, less swollen frontal sinuses, narrower braincase and interorbital region and a narrower mesopterygoid and parapterygoid fossa. The upper incisors in A. caenosus are less orthodont and the molars less hypsodont than A. sylvanus. Additionally, these species show a high average percentage of genetic divergence (6.7%). The differences between A. caenosus and the new species are listed under the treatment of the latter. Distribution: Akodon caenosus is the more broadly distributed species of the boliviensis group in northwestern Argentina, with records from northernmost Salta to southern Catamarca, from 400 m to 3100 m elevation (Fig. 7). Habitat: Most of the records come from Yungas environments, from the lower altitudinal belt to high altitude grasslands. Notwithstanding, we have recorded the species in Chacoan environments near the ecotone with Yungas and in the lower altitudinal limit of the High Andean grasslands. Natural history: Although we have recorded specimens in reproductive condition throughout the year, most of the individuals were active between November and January. We observed the highest proportion of molting animals in fall and winter. In their broad distributional range A. caenosus can be found coexisting with many different species depending on the altitudinal or latitudinal sector in northwestern Argentina. Thus, in the north A. caenosus was captured alongside Akodon sylvanus, A. simulator, Oxymycterus paramensis, Oligoryzomys cf. O. flavescens and Oligoryzomys sp. in high altitudinal grasslands at 1400 m. At the same latitude in upper belts above 2000 m, A. caenosus is sympatric with A. boliviensis, Necromys lactens, N. amoenus, Calomys musculinus (Thomas), Phyllotis caprinus Pearson, P. osilae and P. xanthopygus. In the south, in Yungas areas of Tucum��n province, the species was caught together with Akodon spegazzinii, A. simulator, Necromys lactens, N. lasiurus (Lund), Oxymycterus paramensis, Oxymycterus wayku Jayat et al., Oligoryzomys cf. O. flavescens, Oligoryzomys sp., Phyllotis anitae, P. osilae, Andinomys edax and Abrothrix illutea. At this same latitude in Chacoan environments in transition with Yungas A. caenosus is sympatric with Akodon spegazzinii, A. simulator, Necromys sp., Oligoryzomys cf. O. flavescens, Oligoryzomys sp., Calomys sp. and Graomys centralis. Comments: Although originally described as a subspecies of Akodon puer (Thomas 1918), the form caenosus was soon considered as a valid species by Thomas (1920); this latter suggestion was followed by Cabrera (1961), Barquez et al. (1980), and Mares et al. (1981). Vitullo et al. (1986) and Apfelbaum & Reig (1989) considered specimens from Le��n, Jujuy Province (type locality of caenosus) as A. puer and Myers et al. (1990) followed this position (but see Hershkovitz 1990), considering caenosus as the subspecies of A. puer inhabiting northwestern Argentina (see also Barros et al. 1990). Anderson (1997) also recognized three subspecies for A. puer but noted the priority of the name lutescens over puer. Since then, the nomenclature used for this species has been constantly changing. Capllonch et al. (1997) and Mares et al. (1997) listed caenosus as valid species whereas D��az et al. (1999, 2000) recognized caenosus as subspecies of puer for the populations of the northwestern Argentina. Notwithstanding, D��az (1999) and D��az & Barquez (2007) considered again the nominal form caenosus as representing a valid biological species including A. lutescens puer as an additional sigmodontine species in northwestern Argentina. Musser & Carleton (2005) and Pardi��as et al. (2006) followed the conclusions of Myers et al. (1990). D��az et al. (1999) described Akodon aliquantulus, from the ecotone between upper Yungas forest and highland grassland in Tucum��n province (Las Ag��itas, Cumbres del Taficillo, 1700 m, 26�� 42��� S, 65�� 22��� W), and related it to the A. boliviensis group on the basis of its morphology. The unimpressive morphological distinction from A. lutescens, based only on multivariate ordinations and univariate overlap, induced some authors to recommend a revision of the status of this form (Musser & Carleton 2005; Jayat et al., 2008a). This species was diagnosed and differentiated from A. caenosus (as A. puer caenosus) and A. spegazzinii on the account of being smaller in a number of measurements and the ���weakly developed eye ring��� of two individuals originally preserved in fluid and then prepared as skin plus skull. We could not distinguish the type specimens of A. aliquantulus from A. caenosus following the diagnosis provided by D��az et al. (1999). Most of the characters used for the diagnosis of A. aliquantulus (centered, as said, on a few external and cranial dimensions) are subtle, highly variable in many sigmodontine species, and what is most important are age-dependent. Although D��az et al. (1999) considered the two specimens as old individuals (age-class 5) our observations indicate that they must be assigned to the age class 4 of Myers (1989) (Figure 8). The morphometric distinction between A. aliquantulus and A. caenosus was based on a PCA analysis with a relatively low explained variance (63.3%, 7.9% and 5.1% for components 1, 2 and 3 respectively) and the statistic significance of the observed differences was not provided by the authors. We think that the erroneous assignment of age for the two specimens by D��az et al. (1999) misinform their conclusions. The analysis of table 1 of D��az et al. (1999) clearly indicates the overlap between A. aliquantulus specimens and A. caenosus exemplars of ageclass 4 (see also Table 9 of this work). Remarkably, even some of the diagnostic skull measurements (e.g. braincase breadth, maxillary toothrow length) are included in the observed range for age-class 5 individuals of A. caenosus. Moreover, all the characters mentioned in the description of A. aliquantulus are within the levels of morphological variation observed in A. caenosus of Northwestern Argentina. Therefore, we find no defensible argument to consider A. aliquantulus as a distinct species and consider it a junior synonym of A. caenosus., Published as part of J. Pablo Jayat, Pablo E. Ortiz, Jorge Salazar-Bravo, Ulyses F. J. Pardi��as & Guillermo D'El��a, 2010, The Akodon boliviensis species group (Rodentia: Cricetidae: Sigmodontinae) in Argentina: species limits and distribution, with the description of a new entity, pp. 1-61 in Zootaxa 2409 on pages 23-25, DOI: 10.5281/zenodo.293461, {"references":["Thomas, O. (1918) On small mammals form Salta and Jujuy collected by Mr. E. Budin. Annals and Magazine of Natural History, (9) 1, 186 - 193.","Galliari, C. A., Pardinas, U. F. J. & Goin, F. J. (1996) Lista comentada de los mamiferos argentinos. Mastozoologia Neotropical, 3, 39 - 61.","Diaz, M. M., Barquez, R. M., Braun, J. K. & Mares, M. A. (1999) A new species of Akodon (Muridae: Sigmodontinae) from Northwestern Argentina. Journal of Mammalogy, 80, 786 - 798.","Myers, P., Patton, J. L. & Smith, M. F. (1990) A review of the boliviensis group of Akodon (Muridae: Sigmodontinae) with emphasis on Peru and Bolivia. Miscellaneous Publications of the Museum of Zoology, University of Michigan, 177, 1 - 89.","Barquez, R. M., Williams, D. F., Mares, M. A. & Genoways, H. H. (1980) Karyology and morphometrics of three species of Akodon (Mammalia: Muridae) from northwestern Argentina. Annals of Carnegie Museum, 49, 379 - 403.","Diaz, M. M. (1999) Mamiferos de la Provincia de Jujuy: Sistematica, distribucion y ecologia. Unpublished D. Phil. Thesis, Universidad Nacional de Tucuman, Argentina, 640 pp.","Vitullo, A. D., Merani, M. S., Reig, O. A., Kajon, A. E., Scaglia, O., Espinosa, M. B. & Perez-Zapata, A. (1986) Cytogenetics of South American Akodont Rodents (Cricetidae): new kariotypes and chromosomal banding patterns of argentinian and uruguayan forms. Journal of Mammalogy, 67, 69 - 80.","Thomas, O. (1920 a) A further collection of mammals from Jujuy. Annals and Magazine of Natural History, (9) 5, 195 - 196.","Cabrera, A. (1961) Catalogo de los mamiferos de America del Sur. Parte II. Revista del Museo Argentino de Ciencias Naturales \" Bernardino Rivadavia \", Zoologia, 4 (2), 309 - 732.","Mares, M. A, Ojeda, R. A. & Kosco, M. P. (1981) Observation on the distribution and ecology of the mammals of Salta Province, Argentina. Annals of Carnegie Museum, 50, 151 - 206.","Apfelbaum, L. I. & Reig O. A. (1989) Allozyme genetic distances and evolutionary relationships in species of akodontine rodents (Cricetidae: Sigmodontinae). Biological Journal of the Linnean Society, 38, 257 - 280.","Hershkovitz, P. (1990) Mice of the Akodon boliviensis size class (Sigmodontinae, Cricetidae), with the description of two species from Brazil. Fieldiana, Zoology, new series, 57, 1 - 35.","Barros, M. A., Liascovich, R. C., Gonzalez, L., Lizarralde, M. S. & Reig, O. A. (1990) Banding pattern comparison between Akodon iniscatus, and Akodon puer (Rodentia, Cricetidae). Zeitschrift fur Saugetierkunde, 55, 115 - 127.","Anderson, S. (1997) Mammals of Bolivia, taxonomy and distribution. Bulletin of the American Museum of Natural History, 231, 1 - 652.","Capllonch, P., Autino, A., Diaz, M. M., Barquez, R. M. & Goytia, M. (1997) Los mamiferos del Parque Biologico Sierra de San Javier, Tucuman, Argentina: observaciones sobre su sistematica y distribucion. Mastozoologia Neotropical, 4, 49 - 71.","Diaz, M. M., Braun, J. K., Mares, M. A. & Barquez, R. M. (1997) Key of Mammals of Salta Province, Argentina. Occasional Papers of the Oklahoma Museum of Natural History, 2, 1 - 10.","Diaz, M. M., Braun, J. K., Mares, M. A. & Barquez, R. M. (2000) An update of the taxonomy, systematics, and distribution of the mammals of Salta province, Argentina. Occasional Papers of the Oklahoma Museum of Natural History, 10, 1 - 52.","Diaz, M. M. & Barquez, R. M. (2007) The Wild Mammals of Jujuy Province, Argentina: Systematics and Distribution. In: Kelt, D. A., Lessa, E. P., Salazar-Bravo, J. & Patton, J. L. (Eds.), The Quintessential Naturalist: Honoring the Life and Legacy of Oliver P. Pearson. University of California Publications in Zoology 134, pp. 417 - 578.","Musser, G. M. & Carleton, M. D. (2005) Superfamily Muroidea .. In: Wilson, D. E. & Reeder, D. M. (Eds.) Mammal species of the world: A taxonomic and geographic reference. Third ed. Baltimore: John Hopkins University Press, pp. 894 - 1531.","Jayat, J. P., Ortiz, P. E., Teta, P., Pardinas, U. F. J. & D'Elia, G. (2006) Nuevas localidades argentinas para algunos roedores sigmodontinos (Rodentia: Cricetidae). Mastozoologia Neotropical, 13, 51 - 67.","Jayat, J. P., Ortiz, P. E. & Miotti, M. D. (2008 a) Distribucion de sigmodontinos (Rodentia: Cricetidae) en pastizales de neblina del noroeste argentino. Acta Zoologica Mexicana, 24, 137 - 177.","Myers, P. (1989) A preliminary revision of the varius group of Akodon (A. dayi, dolores, molinae, neocenus, simulator, toba and varius). In: Redford, K. H. & Eisenberg, J. F. (Eds.), Advances in Neotropical Mammalogy. Gainesville, Florida: Sandhill Crane Press, Inc., pp. 5 - 54."]}

Akodon polopi, new species Akodon sp. sensu Polop, 1989:53. Studies on Neotropical Fauna and Environments 24:53���59. Akodon boliviensis sensu Polop, 1991:115. Revista de la Universidad Nacional de R��o Cuarto 11:115���121. Akodon sp. sensu Pinna-Senn et al., 1992 Mendeliana 10: 59���70. Akodon alterus sensu Priotto et al., 1996:135. Facena 12: 135���138. Akodon boliviensis sensu Morando & Polop, 1997:132. Mastozoolog��a Neotropical 4 (2): 129���136. Akodon spegazzinii sensu D���El��a, 2003: 310. Cladistics 19:307���323. Akodon spegazzinii sensu D���El��a et al., 2003:354. Mammalian Biology 68:351���364. Akodon spegazzinii sensu Kufner et al., 2004:120. Ecolog��a Aplicada 3 (1,2):118���121. Akodon spegazzinii sensu Pardi��as et al., 2005: 473. Journal of Mammalogy 86 (3):462���474. Akodon spegazzinii sensu Rodrigues Gon��alvez et al., 2007: 23. Miscellaneous Publications of the Museum of Zoology, University of Michigan 197: 1���24. Akodon spegazzinii sensu Smith & Patton, 2007: 831. University of California Publications in Zoology 134:1���981. Akodon sp. sensu Jayat et al., 2007a: 203. Mastozoolog��a Neotropical 14 (2):201���225. Holotype: MACN 23486, Adult male (age class 4), collected by J. Pablo Jayat, Pablo E. Ortiz, Daniel Garc��a Lopez, and Rodrigo Gonzalez on August 17, 2008 (original field number JPJ 2125), skin, skull, skeleton and tissues in alcohol (Figs. 12 and 13). Type locality: Pampa de Achala, 6 km E (by highway 34) from antena repetidora La Posta, 2200 m (31�� 36��� 44.5��� S, 64�� 48��� 48.7��� W), San Alberto Department, C��rdoba Province, Argentina (Fig. 14). Diagnosis: A member of the Subfamily Sigmodontinae distinguishable from all other species of Akodon by the following combination of characters: size intermediate for the genus (mean values in mm for individuals of age class 4; length of head and body, 100; tail length, 70; condyloincisive length, 24.53; maxillary toothrow length, 4.40); fur dense and soft; general coloration uniform, buffy brown; chin with a small but distinguishable white patch; claws on fore and hind feet somewhat long (mean values in mm for 10 individuals of age class 4 in the medial finger: 2.81 and 3.26 respectively); skull with the rostrum relatively short and broad; interorbital region hour-glass shaped but with sharply squared posterior margins; temporal and lambdoid ridges well developed; zygomatic plate relatively broad; mesopterygoid fossa narrow. Upper incisors slightly proodont; first lower molar with a conspicuous metastylid and mesostylid. Molecular apomorphies are listed in Table 13 (note that sequences of some Akodon species were not analyzed, and that only three haplotype of Akodon polopi, new species were available; therefore, these character states should be taken with caution). Measurements of the holotype: External measurements (in mm): length of head and body, 103; tail length, 76; length of hind foot (with claw), 25; ear length, 15; weight (in g): 35. Cranial measurements (in mm): greatest length of skull, 26.80; condyloincisive length, 25.50; zygomatic breadth, 13.84; braincase breadth, 11.84; interorbital constriction, 4.58; maxillary toothrow length, 4.60; nasal length, 10.10; mid rostral width, 5.00; diastema length, 7.12; length of incisive foramen, 6.54; width across occipital condyles, 6.70; breadth of zygomatic plate, 2.50. See Table 14 for measurements of paratypes. Paratypes: Seven specimens collected at the type locality (CNP 1927, 1928; CML 7672, 7673; and MACN 23487, 23488, 23489) (Table 14). Other referred specimens: Twenty one specimens from the type locality (JPJ 2118, 2120, 2121, 2123, 2126 to 2129, 2131, 2133 to 2135, 2139, 2141, 2144, 2146, 2147, 2149, 2150, 2158, 2159); four specimens from Pampa de Achala (CUNRC 2805, 10145, 10178, 50151); three specimens from Pampa de Achala, 2163 m (CUNRC 44748, 44749, 44750); three specimens from Pampa de Achala, 2247 m (CUNRC 44744, 44745, 44747), and nine specimens from Repetidora La Posta, Pampa de Achala, 2171 m (CNP 1500 to 1508). Distribution: The new species is only known from few localities in C��rdoba Province, Argentina: Pampa de Achala, a highland plateau situated in the Sierras Grandes (Polop 1989, 1991), three localities in R��o Cuarto Department (Cerro de Oro, Puesto Gonzalez and La Ventana, all above 1500 m elevation; Priotto et al. 1996), and two additional sites in Pampa de San Luis, Cruz del Eje Department (SW of Pampa de San Luis, 1900 m, and near Cuchilla Nevada, 1700-1800 m; Kufner et al. 2004) (Fig. 14). Etymology: Dedicated to our friend and colleague Jaime Jos�� Polop (Universidad Nacional de R��o Cuarto, C��rdoba, Argentina) for his invaluable contributions to the understanding of the ecology of sigmodontine rodents from central Argentina. In addition, Jaime collected many of the specimens used in the characterization of the new species and even pointed-out the distinctiveness of this form (Polop 1989: 58). Morphological description: Fur dense and soft. Dorsal coloration uniform, buffy brown lightly spattered with black hairs. Guard hairs generally black excepting those from the rump, which are distally whitish. In this region, the guard hairs extend beyond the level of the fur hairs by approximately 5 mm. Flanks coloration clearer and more richly colored. Ventral side clearly contrasting with dorsum and flanks, with buffy or tawny tinges. Chin with a small but distinguishable white patch. Ears densely covered by hairs of the same general color as the dorsum. Fore and hind feet whitish or buffy and densely furred. Tail clearly bicolored, blacky brown dorsally and whitish ventrally. Claws on fore and hind feet somewhat longer than in the other species of the boliviensis group and densely covered by a whitish tuft. Skull heavily constructed in the context of the boliviensis group, with the rostrum relatively short and broad. Nasals short, not acuminate, and extended almost to the anterior face of incisors; frontal sinuses clearly inflated and zygomatic notches broad and deep. Interorbital region hour-glass shaped, with rounded or lightly squared borders and with posterior margins having a greater tendency to be sharply squared than is usually the case for the boliviensis group. Temporal and lambdoid ridges well developed for this group. Zygomatic plate relatively broad, with its anterior margin straight and vertical in most of the individuals. Hamular process relatively robust but showing a variable development, with distal end expanded. Incisive foramina long, with posterior ends reaching the hypoflexus of M1. Mesopterygoid fossa narrow, with its anterior margin rounded and lateral borders slightly divergent backward. Posterior palatal pits small and variable in position. Parapterygoid fossae slightly excavated and broader than mesopterygoid fossa, with lateral margins generally straight and divergent posteriorly. Auditory bullae of intermediate size for the genus, with short and wide Eustachian tubes. Mandible similar to the remaining species of the boliviensis group but somewhat more robust, with the horizontal ramus higher and the coronoid process broader. The capsular projection clearly posterior to the coronoid process. Anterior point of diastema located below the alveolar plane. The angular process ends just ahead the condyloid process. Masseteric crest reachs the level of the anterior margin of m1 or slightly behind. Teeth of typical Akodon pattern (Fig. 15). Upper incisors approximately orthodont, but many individuals somewhat proodont. M1 with procingulum and anteromedian flexus well developed. A small anteroloph and mesoloph are present on the labial side and on the lingual side a tiny enteroloph is visible in some young specimens. M2 with a reduced procingulum and a vestigial mesoloph present. The posteroflexus not well developed. M3 shows the paraflexus and metaflexus always present in young specimens. The hypoflexus is present in only a few individuals. Lower molars crested and transversally compressed. The m1 has a well developed procingulum with a deep anteromedian flexid and a clearly defined anterolabial cingulum. All the young individuals bear a well-developed ectostylid. On the lingual side, young individuals (age classes 1 and 2) show a well-developed metastylid and a relatively robust mesolophid. The m2 preserves an anterolabial cingulum and a small ectostylid but the mesolophid is vestigial. The m3 is large and ���S��� shaped. Akodon polopi has 13-14 thoracic ribs; the vertebral column includes 13-14 thoracic, 8 lumbar, and 26-27 caudal vertebrae (n = 6). Karyotype: 2n = 40. The autosomal pairs 1 to 18 are telocentric and the pair 19 is metacentric. The X chromosomes are subacrocentric and the Y is small metacentric (Polop 1989; Pinna-Senn et al. 1992). Variation: In spite of marked uniformity in fur coloration, we observed slightly darker and more richly colored specimens. Some individuals have a more slender zygomatic plate, with a slightly concave anterior margin, which determine shallower zygomatic notches. The hamular process also shows a variable development, more delicate in some specimens. The posterior palatal pits also vary in position with regard to the anterior border of the mesopterygoid fossa. Comparisons: Akodon polopi is one of the largest and more robust species of the A. boliviensis group. The species is distinguishable from the remaining species by their denser and softer fur, a large skull, with broad rostrum, deep and broad zygomatic notches, and well-expanded zygomatic arches. However, the new species has a comparatively short rostrum, narrow interorbital constriction and a not inflated braincase. A comparatively well developed metastylid in m1 of young individuals is another distinctive feature of A. polopi. In addition to the previously mentioned characteristics, the new species can be differentiated from Akodon boliviensis by the interorbital region with its posterior margins sharply squared, temporal and lambdoid ridges well developed, and the M3 that does not show an ���8��� shape. The numerous morphometric differences between these species include 17 of the 20 measurements analyzed (Table 2). Cyt b haplotypes of A. polopi and A. boliviensis differ by an average of 5.0% (Table 12). Akodon boliviensis was registered in Argentina only in its northernmost end, always above 2400 m, whereas A. polopi lives below 2300 m on isolated mountain ranges from central Argentina, almost 900 km toward the south. Like A. boliviensis, Akodon caenosus does not have a sharply squared interorbital posterior region or well developed temporal and lambdoid ridges. A. caenosus is unmistakable because it is situated at the opposite end in the morphometric range values, with no overlap in most of the analyzed measurements (Table 1) being all of them statistically different (Table 2). Likewise, cyt b haplotypes of A. polopi and A. caenosus are very divergent (6.2%). A. polopi can be differentiated from Akodon spegazzinii by many characteristics. The former has an interorbital region with posterior margins more sharply squared, temporal and lambdoid ridges more developed and a proportionally shorter molar series. The morphometric differences between these species include 14 of the 20 analyzed measurements (Table 2). Cyt b haplotypes of A. spegazzinii and A. polopi differ by on average 5.5%. Akodon sylvanus is very similar to A. polopi in many of the variables we measured, with less than 50% (9 of 20) significantly different. However, the DA efficiently separated both species and no reciprocally misclassified specimens occurred. The anterior region of the skull of A. polopi is shorter and more robust, the zygomatic notches are deeper and broader, and the braincase is less inflated. In ventral view, the mesopterygoid fossa in A. polopi is narrower, and the upper incisors tend to be more prodont. The cyt b haplotypes of A. sylvanus and A. polopi differ on average by 4.7 %. Like A. boliviensis, A. sylvanus appears to show a disjunct distribution with regards to A. polopi; thus far, A. sylvanus is known from only the neighborhood of its type locality in the Sierra de Santa B��rbara in Yungas forest habitats almost 800 km to the north of the type locality of A. polopi. Natural history: The habitat in Pampa de Achala is characterized by extensive highland grasslands dominated by Festuca and Stipa, between 1800 and 2300 m elevation (Fig 16). Intermingled with the grasslands there are scattered small patches of woodlands of Polylepis australis, Heterothalamus alienus, Eupatorium buniifolium, Berberis ruscifolia, Baccharis myrtilloides and Cassia hockeriana, and rocky outcrops (Polop 1989, 1991). None of the specimens that we captured during the end of winter 2008 (August) showed signs of reproductive activity. These data suggest that the species is reproductively active in the late spring and summer seasons and agree with previous studies where the largest number of pregnancy were in Novembre and December (Polop 1989). This author registered an average number of embryos per female of 4.7 (range 3 to 7). Few of the specimens captured in winter show signs of pelage molting. Other sigmodontine species registered at the type locality and surroundings, in the same habitat, include Oxymycterus rufus (as O. paramensis in Polop 1989), Oligoryzomys flavescens, Phyllotis xanthopygus, and Reithrodon auritus. Akodon polopi, new species is the dominant cricetid in the places where it was registered. In previous studies (Kufner et al. 2004) and our surveys, it constituted more than 70% of the captured animals but Polop (1989, 1991) indicated a minor percentage (53% and 34% respectively). Comments: Although early considered as an undescribed species (Polop 1989), Akodon polopi was alternatively treated as A. boliviensis (Polop 1991; Morando & Polop 1997), A. alterus (Priotto et al. 1996) or A. spegazzinii (D���El��a 2003; D���El��a et al. 2003; Kufner et al. 2004; Pardi��as et al. 2005; Rodrigues Gon��alvez et al. 2007 and Smith & Patton 2007)., Published as part of J. Pablo Jayat, Pablo E. Ortiz, Jorge Salazar-Bravo, Ulyses F. J. Pardi��as & Guillermo D'El��a, 2010, The Akodon boliviensis species group (Rodentia: Cricetidae: Sigmodontinae) in Argentina: species limits and distribution, with the description of a new entity, pp. 1-61 in Zootaxa 2409 on pages 34-42, DOI: 10.5281/zenodo.293461, {"references":["Polop, J. (1989) Distribution and ecological observations of wild rodents in Pampa de Achala, Cordoba, Argentina. Studies on Neotropical Fauna and Environment, 24, 53 - 59.","Polop, J. (1991) Distribucion de cricetidos en las Sierras de Achala (provincia de Cordoba, Republica Argentina). Revista de la Universidad Nacional de Rio Cuarto, Zoologia, 11, 115 - 121.","Pinna-Senn, E., de Barale, D. D., Polop, J. J., Ortiz, M. Y., Provensal, M. C. & Lisanti, J. A. (1992) Estudio cariotipico y morfometrico en una poblacion de Akodon sp. (Rodentia, Cricetidae) de Pampa de Achala. Mendeliana, 10, 59 - 70.","Priotto J. W., Morando, M. & Avila, L. (1996) Nuevas citas de roedores de los pastizales de altura de la Sierra de Comechingones, Cordoba, Argentina. Facena, 12, 135 - 138.","Kufner, M. B., Gavier, G. & Tamburini, D. (2004) Comunidades de roedores de pampas de altura en las Sierras Grandes en Cordoba, Argentina. Ecologia Aplicada, 3, 118 - 121","D'Elia, G., Pardinas, U. F. J. & Myers, P. (2005) An introduction to the genus Bibimys (Rodentia: Sigmodontinae): phylogenetic position and alpha taxonomy. In: Lacey, E. & Myers, P. (Eds.), Mammalian Diversification: From Chromosomes to Phylogeography (A Celebration of the Career of James L. Patton). California: University of California Publications in Zoology, pp. 211 - 246.","Smith, M. F. & Patton, J. L. (2007) Molecular phylogenetics and diversification of South American grass mice, genus Akodon. In: Kelt, D., Lessa, E. & Salazar-Bravo, J. (Eds.), Studies in Contemporary Mammalian Biology. Papers Honoring the Remarkable Career of Oliver P. Pearson, 1915 - 2003. California: University of California Publications in Zoology, pp. 827 - 858.","Jayat, J. P., Ortiz, P. E., Pardinas, U. F. J. & D'Elia, G. (2007 a) Redescripcion y posicion filogenetica del raton selvatico (Akodon sylvanus: Rodentia: Cricetidae). Mastozoologia Neotropical, 14, 201 - 225."]}

Objective: This study aims to study the relationship between physical activity levels, measured with accelerometry, and functional fitness in older adults in the Alentejo region, Portugal. Methods: Fifty-five men and 100 women, aged 65 years and over, were evaluated for the intensity of daily physical activity with accelerometers and for functional fitness with the Senior Fitness Test battery. The associations between functional fitness and time spent in physical activity at different intensities were analyzed. Results: Negative associations were found between sedentary activity time and aerobic endurance, upper-body flexibility and agility. On the other hand, mild and moderate physical activity time showed a positive association with strength, upper-body flexibility, agility and aerobic endurance, both on weekdays and on weekends. Similar results were found for the time spent in moderate physical activity. Conclusions: More active older adults exhibit better functional fitness. The results of this study reinforce the importance of promoting physical activity and reducing sedentary behaviors to improve functional fitness and autonomy in the elderly.

Ribeiro, S., Cabral, P., Henriques, R., Bravo, J., Rodrigues, T., & Painho, M. (2018). Modelação do crescimento urbano para a distribuição eficaz das forças de segurança: o caso português. PROELIUM – Revista da Academia Militar, 7(14), 45-68. A segurança é um fenómeno complexo e dinâmico, exigindo novas abordagens dotadas de instrumentos de apoio à decisão adequados. No âmbito das políticas públicas de segurança, o projeto SIM4SECURITY tem como objetivo criar uma solução tecnológica de apoio à decisão que permita melhorar a eficácia da atividade operacional das forças de segurança. Afigurase necessário o estudo da evolução da urbanização para compreender a distribuição espacial da população e a afetação racional de recursos humanos no âmbito da segurança. Este estudo apresenta o resultado das projeções demográficas, e mapas de uso de solo para 2030 e 2040. Ambos permitem compreender a localização da população no futuro e tecer considerações sobre a proximidade das Forças de Segurança às populações. É analisado o grupo etário com mais de 65 anos, dada a sua vulnerabilidade no que respeita ao sentimento de segurança. Verifica-se que cerca de 13% (10%) da população idosa viverá a mais de 10 km de uma instalação policial em 2030 (2040) num quadro geral de decrescimento populacional em todos os grupos etários. Recomenda-se a adaptação das forças de segurança ao novo perfil demográfico da população, sobretudo no interior do País, de forma a garantir o cumprimento eficaz da sua missão. publishersversion published

A Dissertation as a partial requirement to obtain the degree of Master in Statistics and Information Management, specialization in Risk Analysis and Management This paper is devoted to credit risk modelling issues concerning mortgage commercial loans. Mortgage loans are one of the most popular type of loans provided by credit institutions. Like in the case of other loans, the main concern of institutions providing this type of product is a potential inability to recover the amount assigned to their clients (credit risk). In order to prevent possible losses for credit institutions resulting from clients entering in default, it is therefore crucial to study the behaviour of risky clients. This issue can be addressed through several models, namely through the multi-state Markov model, despite it constituting a more unusual approach in the context of dealing with credit risk modelling. The multi-state Markov model is a useful way of describing a process in which an individual moves through a series of states (finite number) in continuous time. By fitting this model to the loans of risky clients, it is possible to estimate the mean sojourn time in each state before a transition occurs, as well as the transition probabilities between the different states assumed by the contracts, therefore providing a relevant modelling framework for event history data. The present work relies upon 2008-13 databases from one of the biggest American companies that act in the secondary mortgage market, the Fannie Mae. Results show that with the application of the multi-state Markov model, contracts signed during 2013 are more propitious to a scenario of recovery when compared to those referring to the year 2008.

Dissertation presented as the partial requirement for obtaining a Master's degree in Statistics and Information Management, specialization in Information Analysis and Management As propensões atuais da mortalidade têm trazido novos desafios em diversas áreas. Para compensar isso, têm surgido vários estudos relacionados com a previsão da mortalidade, a fim de projetar as tendências futuras da mortalidade e assim reduzir o nível de incerteza associado. Porém, a esperança média de vida tem sido constantemente subestimada. Propusemos a avaliar o desempenho de vários modelos na modelação e projeção da mortalidade portuguesa, desagregada por género, entre 1980 a 2010. Concentramos na estrutura de modelos generalizados de idade - período - corte, com o intuito de incorporar o efeito de coorte e averiguar a existência de gerações que compartilham as mesmas características. E adicionalmente, estudamos o impacto do risco de longevidade numa carteira de anuidades vida, através da mensuração do Value at risk e Expected Shortfall. Entre os modelos discutidos o de Renshaw & Haberman apresentou o melhor ajuste e desempenho preditivo para a construção de índices de mortalidade para os homens e para as mulheres, com base nos Critérios de Informação e erros de previsão, respetivamente. Através da análise dos resíduos, detetamos para os modelos sem o parâmetro de coorte, uma estrutura sistemática na população masculina. Indicando assim, a inércia destes modelos em capturar o efeito de coorte, que por sua vez, leva à possibilidade da existência de um efeito de coorte, conforme já revelado em estudo anteriores. Não obstante, analisamos a incerteza nos parâmetros, mediante a construção de intervalos de confiança, através do método de Bootstrap sobre os resíduos para os modelos de Lee & Carte e Renshaw & Haberman, onde averiguarmos que o índice de coorte é o principal responsável pela incerteza na projecção da mortalidade. No geral, esses resultados sugerem que apesar da relevância do efeito de coorte na modelação da mortalidade, o impacto do mesmo se dissipe ao longo do tempo. The current mortality propensity has led to new challenges in many areas. To compensate this, several mortality prediction studies have been conducted to forecast future mortality trends and thereby reduce the associated uncertainty. However, the average life expectancy was being constantly underestimated. We proposed to examine the performance of different models in modelling and forecasting Portuguese mortality from 1980 to 2010, split by gender. We focused on the structure of generalized age-period-cohort models, such we could consider the cohort effect and check the existence of cohorts with the same characteristics. In addition, we examine the impact of longevity risk on a pension fund portfolio by measuring value at risk and expected shortfall. Among the models discussed, Renshaw & Haberman's model provided the best fitting and predictive performance for the men and women, based on Information Criteria and prediction errors. By analysing the residuals, we found a systematic structure in the male population for the models without cohort parameters. This indicates the inertia of these models in capturing the cohort effect, which in turn leads to the possibility of a cohort effect, as shown in previous studies. Nevertheless, we have analysed the uncertainty in the parameters by using the bootstrap method for residues for the Lee & Carte and Renshaw & Haberman models to establish confidence intervals where the cohort parameter is the main cause of uncertainty in the mortality projection. Overall, these results suggest that despite the relevance of the cohort effect in modelling mortality, the influence of the cohort diminishes over time.

Dissertation presented as the partial requirement for obtaining a Master's degree in Statistics and Information Management, specialization in Risk Analysis and Management Population aging and low precautionary savings rates has put European public social systems under strain. As a result, home-ownership among seniors as viable mean of income stream enhancement and welfare for seniors has been boldly encouraged by governments. Thus, equity release instruments for pensioners have been proposed by the market. These products are mostly encompassed in North America where the elderly are less reluctant to express their desire to transform housing into wealth. Still, southern European countries present large home-ownership rates and an aging low income population that may well unlock future demand. Whilst housing is a highly illiquid asset and emotional attachment as well as inconvenience of moving barriers may occur, in recent literature relatively new approaches to monetize homes have undergone major developments. Particularly, this study will be mainly concerned with the risk and profitability analysis of reverse mortgage schemes through actuarial and deep learning techniques in the attempt to conceive a framework that fully encompasses the valuation needs of companies willing to commercialize home equity based products.

Dissertation submitted in partial fulfilment of the requirements for the degree of Statistics and Information Management specialized in Risk Analysis and Management To effectively manage credit score analysis, financial institutions instigated techniques and models that are mainly designed for the purpose of improving the process assessing creditworthiness during the credit evaluation process. The foremost objective is to discriminate their clients – borrowers – to fall either in the non-defaulter group, that is more likely to pay their financial obligations, or the defaulter one which has a higher probability of failing to pay their debts. In this paper, we devote to use machine learning models in the prediction of mortgage defaults. This study employs various single classification machine learning methodologies including Logistic Regression, Classification and Regression Trees, Random Forest, K-Nearest Neighbors, and Support Vector Machine. To further improve the predictive power, a meta-algorithm ensemble approach – stacking – will be introduced to combine the outputs – probabilities – of the afore mentioned methods. The sample for this study is solely based on the publicly provided dataset by Freddie Mac. By modelling this approach, we achieve an improvement in the model predictability performance. We then compare the performance of each model, and the meta-learner, by plotting the ROC Curve and computing the AUC rate. This study is an extension of various preceding studies that used different techniques to further enhance the model predictivity. Finally, our results are compared with work from different authors. Para gerir com eficácia a análise de risco de crédito, as instituições financeiras desenvolveram técnicas e modelos que foram projetados principalmente para melhorar o processo de avaliação da qualidade de crédito durante o processo de avaliação de crédito. O objetivo final é classifica os seus clientes - tomadores de empréstimos - entre aqueles que tem maior probabilidade de pagar suas obrigações financeiras, e os potenciais incumpridores que têm maior probabilidade de entrar em default. Neste artigo, nos dedicamos a usar modelos de aprendizado de máquina na previsão de defaults de hipoteca. Este estudo emprega várias metodologias de aprendizado de máquina de classificação única, incluindo Regressão Logística, Classification and Regression Trees, Random Forest, K-Nearest Neighbors, and Support Vector Machine. Para melhorar ainda mais o poder preditivo, a abordagem do conjunto de meta-algoritmos - stacking - será introduzida para combinar as saídas - probabilidades - dos métodos acima mencionados. A amostra deste estudo é baseada exclusivamente no conjunto de dados fornecido publicamente pela Freddie Mac. Ao modelar essa abordagem, alcançamos uma melhoria no desempenho do modelo de previsibilidade. Em seguida, comparamos o desempenho de cada modelo e o meta-aprendiz, plotando a Curva ROC e calculando a taxa de AUC. Este estudo é uma extensão de vários estudos anteriores que usaram diferentes técnicas para melhorar ainda mais o modelo preditivo. Finalmente, nossos resultados são comparados com trabalhos de diferentes autores.

Dissertation presented as the partial requirement for obtaining a Master's degree in Statistics and Information Management, specialization in Risk Analysis and Management This paper develops and applies an empirical framework to managing and measuring the longevity risk using derivative instruments, with the aim of suppressing the normal difficulties present in pricing the premium of this type of instruments. More precisely is developed a longevity swap using United States and Japan mortality data, creating a flexible and versatile approach for pricing swap instruments through the risk neutral simulation method. This method is calculated by forecasting survival probabilities, which were estimated and simulated by predicting the mortality parameters applying log bilinear Lee-Carter model across 60 years of both countries data (1954-2014). Using this approach and both countries empirical data is offered a comparative analysis across genders, different type of ages and risk levels. This way it’s possible to expand and test the previous literature contributions and flaws, proving that derivatives are a way to manage the longevity risk in large quantities, which should be considered by insurance companies.

Dissertation presented as the partial requirement for obtaining a Master's degree in Statistics and Information Management, specialization in Risk Analysis and Management Os aumentos da longevidade humana registados a nível global nas últimas décadas, constituem uma das maiores preocupações do sistema público de pensões, companhias de seguros e patrocinadores de fundos de pensões. Para fazer face a esta problemática, têm vindo a ser desenvolvidos diferentes produtos de cobertura do risco de longevidade assentes em soluções de mercado de capitais em alternativa às tradicionais soluções de seguro e resseguro. Esta dissertação teve como objetivo a estimação dos preços de dois tipos de obrigações de longevidade, straight bonds e deferred longevity bonds com uma estrutura contratual idêntica à proposta em 2004 pelo EIB. Esta simulação empírica, baseia-se nos dados de mortalidade para a população dos EUA no intervalo de tempo entre 1980 a 2016 e na utilização do modelo de Poisson-Lee-Carter Poisson para modelar a dinâmica estocástica das taxas de motalidade. Para estimar o prémio de risco de longevidade recorre-se a duas abordagens distintas: Wang Transform e Sharpe Ratio. Este estudo permitiu realizar esta análise por género, diferentes idades e maturidades, e níveis de risco. Desta forma, pretende-se dar um contributo para a resolução do problema associado ao pricing dos derivados de longevidade e provar que estes devem ser considerados pelas companhias de seguros e fundos de pensões na sua gestão do risco de longevidade. The increases in human longevity recorded globally in recent decades are a major concern of the public pension system, insurance companies and pension fund sponsors. To address this problem, different longevity risk hedging products based on capital market solutions have been developed as an alternative to traditional insurance and reinsurance solutions. This dissertation aimed to estimate the prices of two types of longevity bonds, straight bonds and deferred longevity bonds, with a contractual structure identical to the one proposed in 2004 by the EIB. This empirical simulation is based on mortality data for the US population in the time span between 1980 and 2016 and on the use of the Poisson-Lee-Carter Poisson model to model the stochastic dynamics of the mortality rates. To estimate the longevity risk premium, we used two distinct approaches: Wang Transform and Sharpe Ratio. This study allowed to perform this analysis by gender, different ages and maturities, and risk levels. Thus, it is intended to contribute to the solution of the problem associated with the pricing of longevity derivatives and to prove that they should be considered by insurance companies and pension funds in their longevity risk management.

Project Work presented as the partial requirement for obtaining a Master's degree in Statistics and Information Management, specialization in Risk Analysis and Management No setor Segurador, o estado de solvência de uma Companhia é de extrema importância. As Seguradoras, de forma a cumprir as responsabilidades assumidas perante os segurados, devem constituir e manter as provisões técnicas adequadas. Caso contrário, um provisionamento incorreto das responsabilidades pode comprometer a sua solvência. Grande parte do passivo das Seguradoras do Ramo Não Vida é representado pelas provisões técnicas, das quais se destacam, devido à sua importância, as provisões para sinistros. O objetivo principal do presente estudo é analisar os montantes das provisões para sinistros do Ramo Automóvel de uma Companhia de Seguros no período entre 2009 a 2016. Embora existam diversas metodologias de cálculo de provisões para sinistros, recorre-se a métodos estatísticos de previsão, que se baseiam na experiência passada. Em particular, são aplicados métodos determinísticos e estocásticos, nomeadamente o método determinístico Chain Ladder e a técnica de reamostragem Bootstrap associada a este método e, o método estocástico proposto por Thomas Mack. Em resultado, são obtidas estimativas da provisão para sinistros e respectivos intervalos de confiança. Por fim, analisa-se e compara-se os resultados obtidos através destes métodos com os dados disponibilizados pela Companhia.

Dissertation presented as the partial requirement for obtaining a Master's degree in Information Management, specialization in Knowledge Management and Business Intelligence A maior herança da Grande Recessão (crise financeira de 2007/08 e crise das hipotecas subprime dos EUA de 2007/09) é definitivamente a queda da indústria bancária e a incapacidade dos países de reembolsar a sua dívida soberana e aumentar o seu PIB. As ligações são inegáveis e os Bancos Centrais foram responsáveis por uma resposta rápida para reverter essa queda a pique. Esta dissertação pretende analisar o efeito de taxas de juro baixas acrescido de uma política específica adotada pelo Banco Central Europeu (BCE), a saber, a Política de Taxas de Juros Negativos (Negative Interest Rate Policy - NIRP) na rentabilidade dos bancos em Portugal. Em essência, o principal objetivo desta dissertação é entender como a Política de Taxas de Juros Negativas moldaram o setor bancário em Portugal. Identificamos e analisámos os cinco principais canais pelos quais o NIRP impacta a rentabilidade dos bancos, nomeadamente o Canal de Taxa de Juros, o Canal de Crédito, o Canal de Carteira de Ativos, o Canal de Reflação e o Canal de Câmbio. Utilizámos modelos de Regressão Linear Múltipla combinados com uma Regressão Stepwise para identificar as variáveis mais significativas na explicação da rentabilidade e desempenho dos bancos. Este método é comumente usado em estudos similares. Considerámos múltiplas variáveis explicativas, incluindo taxas de juro diretoras do BCE (taxas de facilidade permanente de depósito e de facilidade permanente de cedência marginal de liquidez), taxas de juros do mercado monetário interbancário, variáveis específico do setor financeiro (por exemplo, rácio custo / rendimento, rácio Crédito / Depósito) e variáveis macroeconómicas (Crescimento real do PIB, taxa de desemprego). Recorremos a dados publicamente disponíveis, para 35 bancos diferentes, de 2010 a 2017, fornecidos pela Associação Portuguesa de Bancos (APB), pelo Banco de Portugal (BdP), pelo BCE e pelo Instituto Europeu para os Mercados Monetários (EMMI). Durante este período, os bancos portugueses fizeram algumas mudanças nas suas estratégias de negócio, aumentando o foco nas comissões e comissões de serviço e maiores retornos da gestão de carteiras. Depois de executar os modelos e analisar os resultados, podemos concluir que quando o BCE decidiu utilizar o NIRP, como forma de recuperar a economia europeia, os canais que mais afetaram a rentabilidade do banco português foram o Canal de Taxa de Juro, o Canal de Crédito e o Canal de Carteira de Ativos. The aftermath of the Great Recession (financial crisis of 2007/08 and U.S. subprime mortgage crisis of 2007/09) and the Euro Zone Sovereign Debt Crisis is definitely the fall of the Banking industry and the countries incapability of repaying their debts. The world economy suffered a major setback and Governments and Central Banks had to provide actions to regain the financial strength they once had. A quick response was demanded in order to reverse this tsunami of downfalls that jeopardized the economical actors. This paper intends to analyse the effects of negative interest rates plus a specific policy adopted by the European Central Bank (ECB), namely the Negative Interest Rates Policy (NIRP), on banks’ profitability in Portugal. We identified and analysed the five main channels by which NIRP impacts on banks’ profitability, namely the Interest Rate Channel, the Credit Channel, the Portfolio Channel, the Reflation Channel and the Exchange Rate Channel. We used Multiple Linear Regression models combined with a Stepwise Regression to identify the most significant variables in explaining bank's profitability and performance. This method is commonly used in similar related studies. We considered multiple explanatory variables, including ECB key interest rates (deposit and facility rates), Interbank Money Market Interest Rates, Bank Specific covariates (e.g., Cost-to-Income ratio, Loan-to-Deposit ratio) and macroeconomic variables (e.g., real GDP Growth, unemployment rate). We use publicly available data for 35 different banks from 2010 to 2017 provided by Portuguese Banking Association (Associação Portuguesa de Bancos, APB), Bank of Portugal (Banco de Portugal, BdP), ECB and European Money Markets Institute (EMMI). During this period Portuguese banks made some changes in their business strategies, increasing the focus on servicing fees and commissions and higher returns from portfolio management. After executing the models and analysing the results, we can conclude that when ECB decided to use NIRP, as a mean to recover the European economy, the channels that most affected Portuguese bank’s profitability, were the Interest Rate Channel, the Credit Channel and the Portfolio Channel.

Dissertation presented as the partial requirement for obtaining a Master's degree in Statistics and Information Management, specialization in Risk Analysis and Management A estrutura temporal das taxas de juro, também conhecida por yield curve ou curva de rendimentos define a relação entre as taxas de juros e o prazo de vencimento (ou maturidades) dos investimentos feitos. Assim, o desenvolvimento de modelos que possibilitem a obtenção de previsões precisas sobre a estrutura temporal das taxas de juro e que permitam estudar a dinâmica da evolução das taxas de juro é de crucial importância em diversas áreas de financiamento. Neste estudo investigou-se a performance de diferentes métodos de previsão para obter a estrutura temporal das taxas de juro da Zona Euro, considerando o período entre 2009 e 2015. Em termos mais específicos, foi analisada a capacidade preditiva do modelo de Nelson-Siegel & Svensson assumindo que os parâmetros resultantes da estimação da especificação paramétrica podem ser modelizados através de métodos de séries temporais univariados (modelos ARIMA, Random walk) e multivariados (modelos VAR) e Redes Neuronais Artificiais (RNA) individuais e conjuntas. Os resultados deste estudo mostram que (i) as RNA com a previsão dos parâmetros em simultâneo exibem os valores de erro mais baixos para as maturidades de curto e médio prazo (3 meses a 5 anos); (ii) As RNAs individuais são melhores para prever as taxas de juro nas maturidades compreendidas entre os 7 e os 10 anos, e que (iii) para as maturidades de longo e muito longo prazo (15 e 30 anos respetivamente) deverá ser escolhido o modelo VAR(1). Estes resultados são robustos e consistentes para todos os horizontes de previsão analisados (1,2 e 3 meses). Contudo, no período analisado nenhum dos modelos testados apresenta valores de erro inferiores aos obtidos com o modelo Random Walk.

A thesis submitted in partial fulfillment of the requirements for the degree of Doctor in Information Management, specialization in Statistics and Econometrics This thesis worked on the application of advanced survival models in consumer credit risk assessment, particularly to address issues of recurrent delinquency (or default) and recovery (cure) events as well as multiple risk events and frailty. Each chapter (2 to 5) addressed a separate problem and several key conclusions were reached. Chapter 2 addressed the neglected area of modelling recovery from delinquency to normal performance on retail consumer loans taking into account the recurrent nature of delinquency and also including time-dependent macroeconomic variables. Using data from a lending company in Zimbabwe, we provided a comprehensive analysis of the recovery patterns using the extended Cox model. The findings vividly showed that behavioural variables were the most important in understanding recovery patterns of obligors. This confirms and underscores the importance of using behavioural models to understand the recovery patterns of obligors in order to prevent credit loss. The findings also strongly revealed that the falling real gross domestic product, representing a deteriorating economic situation significantly explained the diminishing rate of recovery from delinquency to normal performance among consumers. The study pointed to the urgent need for policy measures aimed at promoting economic growth for the stabilisation of consumer welfare and the financial system at large.Chapter 3 extends the work in chapter 2 and notes that, even though multiple failure-time data are ubiquitous in finance and economics especially in the credit risk domain, it is unfortunate that naive statistical techniques which ignore the subsequent events are commonly used to analyse such data. Applying standard statistical methods without addressing the recurrence of the events produces biased and inefficient estimates, thus offering erroneous predictions. We explore various ways of modelling and forecasting recurrent delinquency and recovery events on consumer loans. Using consumer loans data from a severely distressed economic environment, we illustrate and empirically compare extended Cox models for ordered recurrent recovery events. We highlight that accounting for multiple events proffers detailed information, thus providing a nuanced understanding of the recovery prognosis of delinquents. For ordered indistinguishable recurrent recovery events, we recommend using the Andersen and Gill (1982) model since it fits these assumptions and performs well on predicting recovery.Chapter 4 extends chapters 2 and 3 and highlight that rigorous credit risk analysis is not only of significance to lenders and banks but is also of paramount importance for sound regulatory and economic policy making. Increasing loan impairment or delinquency, defaults and mortgage foreclosures signals a sick economy and generates considerable financial stability concerns. For lenders and banks, the accurate estimation of credit risk parameters remains essential for pricing, profit testing, capital provisioning as well as for managing delinquents. Traditional credit scoring models such as the logit regression only provide estimates of the lifetime probability of default for a loan but cannot identify the existence of cures and or other movements. These methods lack the ability to characterise the progression of borrowers over time and cannot utilise all the available data to understand the recurrence of risk events and possible occurrence of multiple loan outcomes. In this paper, we propose a system-wide multi-state framework to jointly model state occupations and the transitions between normal performance (current), delinquency, prepayment, repurchase, short sale and foreclosure on mortgage loans. The probability of loans transitioning to and from the various states is estimated in a discrete-time multi-state Markov model with seven allowable states and sixteen possible transitions. Additionally, we investigate the relationship between the probability of loans transitioning to and from various loan outcomes and loan-level covariates. We empirically test the performance of the model using the US single-family mortgage loans originated during the first quarter of 2009 and were followed on their monthly repayment performance until the third quarter of 2016. Our results show that the main factors affecting the transition into various loan outcomes are affordability as measured by debt-to-income ratio, equity as marked by loan-to-value ratio, interest rates and the property type. In chapter 5, we note that there has been increasing availability of consumer credit in Zimbabwe, yet the credit information sharing systems are not as advanced. Using frailty survival models on credit bureau data from Zimbabwe, the study investigates the possible underestimation of credit losses under the assumption of independence of default event times. The study found that adding a frailty term significantly improved the models, thus indicating the presence of unobserved heterogeneity. The major policy recommendation is for the regulator to institute appropriate policy frameworks to allow robust and complete credit information sharing and reporting as doing so will significantly improve the functioning of the credit market.

Dissertation presented as the partial requirement for obtaining a Master's degree in Statistics and Information Management, specialization in Risk Analysis and Management No presente artigo será medido e analisado o risco de crédito de empresas não financeiras pertencentes ao PSI20 durante os anos 2005 a 2015. Com recurso a um modelo tipo KMV, é obtida a Distance-to-Default e a probabilidade de default destas empresas ao longo do tempo. Posteriormente, através de um modelo de regressão linear múltipla, é testada a relação entre os valores obtidos para a Distance-to-Default e características fundamentais das empresas e variáveis macroeconómicas.

Dissertation presented as partial requirement for obtaining the Master’s degree in Statistics and Information Management, with a specialization in Risk Analysis and Management The recent publication of IFRS 9 facilitates the use of hedge accounting, although some challenges arise as well. Hedge effectiveness is to be more align with risk management meaning that hedge accounting ineffectiveness will now be only related to factors such as counterparty credit risk whenever uncollateralized derivatives are to be used as hedge instruments. This master thesis is concerned with what may go wrong in a designated hedging relationship due to CVA and DVS volatility. Using Monte Carlo simulations and regression analysis the probability of hedging ineffectiveness as a function of probability of default perceived implied volatility is to be modelled. A recente publicação da IFRS 9 facilita o uso da contabilidade de cobertura, ainda que acrescente de igual modo alguns desafios. A contabilidade de cobertura passa a estar mais alinhada com a gestão de risco o que significa que a sua ineficácia passa a estar mais relacionada com fatores com risco de contraparte sempre que se usem derivados não coletaralizados como instrumentos de cobertura. Esta tese de mestrado foca-se no impacto da volatilidade do CVA/DVA na contabilidade de cobertura. Fazendo uso de simulações Montes Carlo e regressões estatísticas, procura-se modelizar a probabilidade de ineficácia das coberturas em função em da volatilidade das probabilidades de default.