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Tamandua Gray, 1825 contains two species of anteaters: Tamandua mexicana (Saussure, 1860), which occurs in southern Mexico, throughout Central America and south to the west of the Andes in South America, and Tamandua tetradactyla (Linnaeus, 1758), widely distributed in South America, from Venezuela to northern Argentina, as well as Trinidad and Tobago. Historically, different coloration patterns have been attributed to the coat of Tamandua, with T. mexicana typically showing a partial or complete dark "vest" on the dorsal portion of the body, whereas T. tetradactyla can show a complete, partial, or absent vest and a coat varying from golden, pale yellow and pale gray to brown or black. These different coat colors are sometimes treated as inherent characteristics of subspecies of Tamandua. Here, we review color variation in Tamandua and describe six chromatic disorders for the genus: albinism, leucism, "brown" variation, melanism (partial and total), xanthochromism (partial and total) and, for the first time for anteaters, erythrism. In addition, we detail the morphological expression and geographic distribution of these anomalies in populations of Tamandua from Central and South America. [ABSTRACT FROM AUTHOR]

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We investigated the occurrence of congenital dental abnormalities in 94 wild boars Sus scrofa scrofa, and 20 Iberian pigs Sus scrofa domesticus from Doñana (DNP) and Sierra de Andújar Natural Park (ANP) southern Spain. The only dental variation found was agenesis of the lower first premolar, either deciduous (Dp1) or permanent (P1). We analyzed prevalence variations using: odds ratios, Fisher's exact test and logistic-regression models. The lower first premolar has often been reported to be absent in modern domestic breeds of pigs, but it is usually reported as present in wild boar. However, we found a similar occurrence of agenesis in wild boar as in Iberian pigs. A common genotypic background between wild boar and Iberian pig populations of ANP sharing the same ecosystems may explain this result. When considering only wild boar, unexpected differences between populations were detected. The wild boar from ANP showed higher estimated probabilities of agenesis than those from DNP. Environmental conditions can also represent influencing factors for changes within subspecies. Our findings reinforce the idea that in suids the congenital absence of premolars probably has an evolutionary relevance, which could represent a generalized trend towards the reduction of the dental formula from the plesiomorphic placental dentition. [ABSTRACT FROM AUTHOR]

Copyright of Revista Internacional de Ciências is the property of Editora da Universidade do Estado do Rio de Janeiro (EdUERJ) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The reasons Lutreolina crassicaudata is always captured in close proximity to water are not clear. We investigated locomotory behavior and performance in swimming, running, climbing, and jumping of L. crassicaudata. One adult male was videotaped in the laboratory while swimming, walking on the ground and on a horizontal tube 1.2 m from the ground, climbing a tree trunk angled 45[degrees], and jumping gaps between supports. The locomotor cycles in these different activities were described by speed, stride length, stroke or stride frequency, time of power and recovery phases or stance and swing phases, and by displacement of points on the animal. L. crassicaudata employed a quadruped paddling gait in swimming. Swimming speed was similar to that of terrestrial didelphids, but stroke frequency and buoyancy ability were more similar to those of the water opossum. Different gaits were used for locomotion in each habitat type and we conclude that L. crassicaudata cannot be considered a specialized species for aquatic locomotion. Key words: animal behavior, climbing, Didelphidae, locomotion, Lutreolina, swimming

Semiaquatic habits evolved in several Sigmodontinae rodent species, but this issue remains poorly studied. The marsh rat Holochilus vulpinus (Brants, 1827) has been associated with palustrine wetland environments and exhibits several morphological traits related to the semiaquatic habit. However, its swimming behavior and the way its morphological specializations contribute to it have not been evaluated so far in this species. This note focuses on describing and quantifying the swimming behavior and swimming performance of H. vulpinus. In order to address these issues, five individuals of H. vulpinus, four adults and one subadult, were filmed while swimming and their performance was quantified. The obtained results indicate that the swimming mode is bipedal paddling, alternating the stroke of the hind feet. The quantitative indicators also qualify H. vulpinus as a good swimmer compared to other terrestrial and semiaquatic mammals. [ABSTRACT FROM AUTHOR]

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The mara Dolichotis patagonum (Caviomorpha, Caviidae) is probably the extant rodent with the most pronounced postcranial specializations for fast locomotion. When running the species can reach a speed of ~40 km/h. It has been suggested that its body posture and limb bones show evolutionary parallelism regarding small-sized artiodactyl species. Due to its elongated limbs and relatively large body mass (average 8 kg) compared to other rodents, its limb bones may experience large loads at high speeds. Using kinematic data from high speed video films and skeletal dimensions of museum specimens, ground reaction forces and stresses acting on the humerus and tibia during different gaits were estimated. Values of bending stress obtained for the tibia were greater than those for the humerus during walking, gallop and "pronk". The stress experienced by the tibia when running doubled the value obtained when walking (54.5 vs. 26.1 MPa, respectively). Estimated bone safety factors were less than half during fast locomotion (3.1) compared to walking (6.4). It is discussed how maras' body posture and skeletal dimensions affect bone stress experienced during locomotion. [ABSTRACT FROM AUTHOR]

Mandibles from separate populations of free-living mouflons (Ovis aries musimon) from Southern Spain, submitted to different ecological conditions, were studied. Searching for ontogenetic shape variations we used geometric morphometrics tools and we explored the use of several mathematical models for describing growth rate variations between populations and sexes. A strong allometry was detected with variations in shape mainly matching with molar and premolar eruption. Mandible shape did not vary significantly with sex nor was sexual size dimorphism detected in adults, whatever the population. By modeling growth we detected differences between populations in all parameters such as the maturity rate describing precocity, and the time it took to reach asymptotic size (varying from 9 up to 18 months). A longer period of growth did not result in a larger asymptotic size, but it led to smaller mandibles. Mouflons with relatively late teeth replacement, lower maturation rate and smaller adult size were those of the population submitted to extreme environmental conditions, like epizootic disease, droughts and ungulate overpopulations. We discuss how a delay in reaching mature size has probably an important subsequent impact on reproductive and life-history traits in this species. Being able to record the effects of density-dependent and densityindependent factors, mandibles become a target of interest for ecological and management studies also on mouflons. [ABSTRACT FROM AUTHOR]

Copyright of Revista Internacional de Ciências is the property of Editora da Universidade do Estado do Rio de Janeiro (EdUERJ) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Internacional de Ciências is the property of Editora da Universidade do Estado do Rio de Janeiro (EdUERJ) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Internacional de Ciências is the property of Editora da Universidade do Estado do Rio de Janeiro (EdUERJ) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Internacional de Ciências is the property of Editora da Universidade do Estado do Rio de Janeiro (EdUERJ) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Internacional de Ciências is the property of Editora da Universidade do Estado do Rio de Janeiro (EdUERJ) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Internacional de Ciências is the property of Editora da Universidade do Estado do Rio de Janeiro (EdUERJ) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Armadillos comprise a particular group of armoured animals whose functional morphology of locomotion remains unclear. For the first time, the kinematic patterns of Dasypus novemcinctus are analysed. Eight specimens of nine‐banded armadillos were studied at a research institute in São Paulo State, Brazil. The individuals were induced to cross a horizontal corridor and each gait performed during the time each of them was kept inside this structure was recorded to a detailed analysis posteriorly performed in a computer program. Four parameters regarding speed range were considered: stride frequency (Hz) (1/stride period), stride length (m), speed (ms−1) and duty factor (%). A total of 89 strides have been analysed among symmetrical (60.6%) and asymmetrical gaits (39.4%), and six footfall patterns were here reported as follows: lateral sequences (symmetrical), transverse gallop, canter, bound, half‐bound and crutch walk (asymmetrical). This kind of analysis implements our knowledge on the locomotory aspects of these animals, hence contributing to the improvement of our knowledge on this still poorly known group. [ABSTRACT FROM AUTHOR]

Copyright of Biota Neotropica (Edicao em Iingles) is the property of Biota Neotropica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article explores the microornamentation of snake scales and its significance. Topics include the use of microornamentation in taxonomy and its historical context, the functional adaptations of microornamentation related to various environmental factors, and the dual influence of phylogenetic history and environmental preferences on the patterns observed in snake scale microstructures.

The echimyid rodents of the genus Phyllomys are medium-sized arboreal spiny rats endemic to the Atlantic Forest of Brazil. The genus is currently composed of 13 species, although there are at least four other undescribed species. The ecology, zoogeography and diversity of the genus are still poorly understood. Here, we provide the first record of Phyllomys sulinus from the Brazilian state of Rio de Janeiro, based on a specimen collected in the Serra da Bocaina National Park, which extends the known geographic range of the species approximately 130 km to the northeast. At this site, P. sulinus occurred in syntopy with the cryptic Phyllomys nigrispinus. We describe the karyotype of P. nigrispinus for the first time and identify two different diploid numbers (2n=84 and 85). We also conducted a molecular analysis of the cytochrome b gene of five specimens, which we identified by phylogenetic reconstruction. Our findings reinforce the importance of molecular data, such as DNA sequences, and karyotypes for the differentiation of cryptic, syntopic species. [ABSTRACT FROM AUTHOR]

The stance of pterosaurs on land is traditionally a controversial question. Here, we show that pterosaurs likeAnhanguera piscatorwere quadrupeds. An osteological model ofA. piscatorwas three-dimensionally built in digital space. The reconstructed muscles of its pelvic girdle were then placed on their points of origin and insertion to allow the biomechanical calculations to find the most efficient stance on land to be performed. The hindlimb readjustment (i.e. the repositioning of the hindlimb according to the achieved results) led to a pelvic counterclockwise displacement at 10°, which means that the ilium previously placed at 0° regarding an axis parallel to the ground was moved (and so the whole pelvis) 10° up from the preacetabular process. This new position preventsA. piscatorfrom having a fully upright stance. A 10° displacement of the pelvic girdle would compel the forelimbs to be highly sprawled. Therefore, this study affordsA. piscatorhaving a quadrupedal gait and demonstrates that a bipedal stance is not viable once the lever arm values decrease abruptly both for extensor and flexor muscles during the femoral extension. This is the first time this approach is used to shed light on this question. [ABSTRACT FROM PUBLISHER]

Abstract: The present study compares the forefoot and hindfoot musculature of five representative species of Cavioidea rodents. In all species, the musculature of both forefeet and hindfeet have the same array regardless of the absence of digit I in the manus of Hydrochaeris hydrochaeris and Cavia porcellus. Our results suggest a tendency in these species towards a three-digit system, with a functional loss of digit V and a predominance of digit III in their forefeet. In the same way, the muscular reduction of digit I in the other rodents analyzed indicates a four-digit system with predominance of digit II in Myoprocta acouchy and Dasyprocta leporina and of digit V in Agouti paca. There seems to be an association between the muscular arrangement and functional axis of the foot, raising the general question why this axis runs between the third and forth digit, or along the third digit. [Copyright &y& Elsevier]

The origin and distribution of the femoral nerves in both antimeres were studied in 30 New Zealand rabbits (15 males and 15 females). The specimens were collected after natural death and fixed with 10% formaldehyde solution. In males, the femoral nerve originated from the ventral branches of the fourth, sixth and seventh lumbar spinal nerves in seven animals (46.67%), in two animals (13.33%) from the ventral branches of the fifth and sixth lumbar spinal nerves, in one animal (6.67%) from the ventral branch of the fifth lumbar spinal nerve, in three animals (20%) from the ventral branches of the fifth, sixth and seventh lumbar spinal nerves, in one animal (6.67%) from the ventral branches of the fourth and fifth lumbar spinal nerves, and in one animal (6.67%) from the ventral branches of the fifth and seventh lumbar spinal nerves. In females, the femoral nerve originated from the ventral branches of the fourth, sixth and seventh lumbar spinal nerves in four animals (26.67%), in two cases (13.33%) from the ventral branches of the fifth and sixth lumbar spinal nerves, in one animal (6.67%) from the ventral branch of the fifth lumbar spinal nerve, in three animals (20%) from the ventral branches of the sixth and seventh lumbar spinal nerves, in four animals (26.67%) from the ventral branches of the fifth, sixth and seventh lumbar spinal nerves and in one animal (6.67%) from the ventral branches of the fourth and seventhlumbar spinal nerves. In all animals the femoral nerves were distributed in different branches to the major and minor psoas, femoral quadriceps, sartorius and pectinius muscles. [ABSTRACT FROM AUTHOR]

The intestines of Sturnira lilium, Phyllostomus hastatus, Carolliaperspicillata, GlossophagasoricinaíindDesmodus rotundus were analized through macroscopic, morphometric and light microscopy studies. The species studied presented some common charactenstics generally found in bats, such as the absence of a caecum and an appendix. The frugivorous bat S. lilium has a longer intestine than the other species. The intestinal epithelium is of the simple columnar type, constituted of absorptive cells characterized by microvilli and goblet cells, which in all the species proved to be PAS + and AB +. These cells presented some differences in quantity and in distribution among the species. The intestinal mucosa presented morphologic and morphometric differences, such as the shape and size of villi as well as the length of the crypts of Lieberkühn. Histologically the different intestinal portions could be distinguished: in the middle portion we found few goblet cells and long villi; in the distal portion we found an increase in goblet cells and a decrease in villi height; and in the large intestine no villi were found, but rather abundant intestinal glands with numerous goblet cells. In C. perspicillata, P. hastatus and G. soricina we could observe Peyeras patches in the distal portion near the large intestine, whereas in D. rotundus and S. lilium we found aggregations of lymphoid nodulous tissue distributed along the tube. In all species we observed the presence of Paneth cells at the base of the crypts of Lieberkühn. We could observe differences among the species in the distribution of collagen in the small intestine submucosa and serosa. The outer muscular layer has one circular layer and a longitudinal layer, the circular layer increasing in thickness along the tube. Large intestine charactenstics are uniform among the species. Sfractures such as the taenia coli and the appendices epiploicae were absent. These results should contribute not only to improve understanding of bat morphology, but also to provide grounds for the evaluation of evolutionary models on the adaptive radiation of phyllostomid feeding habits. [ABSTRACT FROM AUTHOR]

Here we report the first record of Drymoreomys albimaculatus Percequillo, Weksler & Costa, 2011 (Cricetidae, Sigmodontinae) in Rio de Janeiro state, Brazil. One specimen was captured at Serra da Bocaina National Park, municipality of Paraty. The specimen was captured in a pitfall trap, in a mixed habitat of forest and bamboo. The karyotype showed 2n = 62 and FN = 62, which is similar to the previously described for the species. [ABSTRACT FROM AUTHOR]

Morphological variation of the ramus mandibulae of wild Sus scrofa was described and correlated to sex and age differences. Young forms (n=27, 15 males, 12 females) and adults (n=23, 13 males, 10 females) were analyzed through Geometric Morphometrics (2-D) to assess differences between groups. We found significant differences between age- and sex-related shape variations at ramus mandibulae level. Young wild boars present bulky angular process with backward oriented coronoid process, while adults show slender jaw vertical ramus, and orthogonally oriented coronoid process. The ramus mandibulae in female wild boars is more robust and bulky than in males. The morphological changes between young and adult forms are related to alterations in the osteo-muscular jaw complex along wild boars ontogeny. The jaw morphological variations observed in adult wild boars could also be related to dietary differences between sexes. [ABSTRACT FROM AUTHOR]

Here we present a commented list of mammals registered in the Serra da Bocaina National Park. Three field trips (February, 2010, and May and July, 2011) were accomplished along the RJ-165 highway in the Municipality of Paraty, State of Rio de Janeiro, Brazil. Forty-eight species belonging to nine orders were recorded. The local mammal fauna could be considered diverse and rich, with some species regarded as biological indicators of habitat quality. Endangered and rare rodent species like Blarinomys breviceps, Juliomys rimofrons, and Thaptomys nigrita were captured. Road and hunting impacts on mammals are discussed. [ABSTRACT FROM AUTHOR]

The anaconda Eunectes murinus (Linnaeus, 1758) inhabits large hydrographic basins in tropical America and figures among the world's largest snakes, attaining a length of 12 m. This study analyzed the growth of three female anaconda siblings, with records from their birth in captivity up to around 14 months of age. The snakes were kept in a controlled environment with constant temperature and data related to biometry, feeding and skin shedding were recorded. At the end of these 445 days, the siblings had grown on average 2.6 times their initial length and increased their initial weight by 3830.10g, incorporating about 43.5% of total food ingested to their body mass. They showed a total of 0.69 skin sheddings per month in that period, and did not exhibit significant differences in shedding intervals, nor in body growth (weight and length), when compared among themselves. Food was refused at times, coinciding with the days that preceded the ecdyses. Sheddings do not seem to be explained by feeding or growth, which suggests a relation to other endogenous factors. A more detailed study of this species is needed to better understand its growth to the adult phase and its hormonal levels during growth. [ABSTRACT FROM AUTHOR]

Until now, Juliomys rimofrons Oliveira and Bonvicino, 2002 has been known only from the type locality, the county of Itamonte, State of Minas Gerais, Brazil. Based on morphological and karyological examinations, in this study we identified two new records for this species. Both records correspond to individuals collected at Serra da Bocaina National Park, in the states of Rio de Janeiro and São Paulo, Brazil. These records increase the species' geographic range southwards, approximately 100 km from the type locality. [ABSTRACT FROM AUTHOR]