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Ichthyomyini, a morphologically distinctive group of Neotropical cricetid rodents, lacks an integrative study of its systematics and biogeography. Since this tribe is a crucial element of the Sigmodontinae, the most speciose subfamily of the Cricetidae, we conducted a study that includes most of its recognized diversity (five genera and 19 species distributed from southern Mexico to northern Bolivia). For this report we analyzed a combined matrix composed of four molecular markers (RBP3, GHR, RAG1, Cytb) and 56 morphological traits, the latter including 15 external, 14 cranial, 19 dental, five soft-anatomical and three postcranial features. A variety of results were obtained, some of which are inconsistent with the currently accepted classification and understanding of the tribe. Ichthyomyini is retrieved as monophyletic, and it is divided into two main clades that are here recognized as subtribes: one to contain the genus Anotomys and the other composed by the remaining genera. Neusticomys (as currently recognized) was found to consist of two well supported clades, one of which corresponds to the original concept of Daptomys. Accordingly, we propose the resurrection of the latter as a valid genus to include several species from low to middle elevations and restrict Neusticomys to several highland forms. Numerous other revisions are necessary to reconcile the alpha taxonomy of ichthyomyines with our phylogenetic results, including placement of the Cajas Plateau water rat (formerly Chibchanomys orcesi) in the genus Neusticomys (sensu stricto), and the recognition of at least two new species (one in Neusticomys, one in Daptomys). Additional work is necessary to confirm other unanticipated results, such as the non-monophyletic nature of Rheomys and the presence of a possible new genus and species from Peru. Our results also suggest that ichthyomyines are one of the main Andean radiations of sigmodontine cricetids, with an evolutionary history dating to the Late Miocene and subsequent cladogenesis during the Pleistocene. [ABSTRACT FROM AUTHOR]

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Copyright of Therya is the property of Asociacion Mexicana de Mastozoologia, A. C. 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.)

Necromys is a genus of sigmodontine rodent that inhabits grasslands and scrublands in South America. Eight extant species are recognized in the genus; one of these is Necromys lactens , which inhabits high-elevation grasslands in the Yungas from south-central Bolivia to northwestern Argentina. Morphological variation in N. lactens has been recognized by the description of three nominal forms. Geographically structured genetic diversity also has been observed, but a thorough revision of these nominal forms within an integrative framework has yet to be performed. We conducted a phylogeographic assessment based on an 801 base-pair fragment of the cytochrome- b gene that guided morphometric analyses (univariate and multivariate comparisons) of patterns of geographic variation in the species, and the distinction of its nominal forms. Haplotypes of N. lactens form a well-supported and geographically structured clade. Within it, there are two main clades; haplotypes from the northern range form a well-supported clade, sister and allopatric to a weakly supported southern clade, which includes variants collected at or near the type localities of three nominal forms. In turn, both main clades are composed by two allopatric subclades. Morphometric analyses indicated no differences in shape of the skull among the three nominal forms or between the recovered clades and subclades. Taking together all the available evidence, we consider N. lactens to be a monotypic species. Necromys es un género de roedor sigmodontino que habita los pastizales y arbustales de América del Sur. Se reconocen ocho especies actualmente en existencia en el género; una de ellas, Necromys lactens , habita pastizales de altura en las Yungas, desde el centro-sur de Bolivia hasta el noroeste de Argentina. Se ha reconocido variación morfológica en N. lactens con base en descripciones de tres formas nominales; también se ha observado diversidad genética geográficamente estructurada, pero una revisión exhaustiva de esas formas nominales dentro de un esquema integrativo aún no se ha llevado a cabo. Realizamos una evaluación filogeográfica basada en un fragmento de 801 pares de bases del gen citocromo b que orientó análisis morfométricos (comparaciones univariadas y multivariadas) respecto al patrón geográfico de variación de la especie y la distinción de sus formas nominales. Los haplotipos de N. lactens forman un clado bien apoyado y geográficamente estructurado. Dentro de este clado, los haplotipos del norte de su área de distribución forman un clado bien apoyado que es hermano y alopátrico con respecto de un clado austral débilmente apoyado, el cual incluye variantes colectadas en las localidades tipo de las tres formas nominales o sus cercanías. A su vez, ambos clados principales están compuestos por dos sub-clados alopátricos. Los análisis morfométricos no revelaron diferencias en la forma del cráneo entre las tres formas nominales ni entre los clados y sub-clados recuperados. Teniendo en cuenta toda la evidencia disponible, consideramos que N. lactens es una especie monotípica. [ABSTRACT FROM AUTHOR]

The article describes the presence of a known specimen of the cricetid genus Punomys, a new rodent genus, for Bolivia based on an adult female caught in 1987. The specific affinities of the specimen are currently unidentified as it shares qualitative as well as quantitative characters with Punomys kofordi and P. lemminus but also differs significantly from both species. It suggests that the levels of intraspecific variation within the known species of Punomys need to be examined critically and the unique Bolivian specimen is damaged badly enough to prevent the comparison of many taxonomically significant characters.

The article presents a study which examines the development of Chinchillula sahamae during captivity. For the study, researchers analyzed information derived from observations over a 25-week period of a wild-caught, captive adult female chinchilla rat and its offspring. The female chinchilla rat was found in Ulla Ulla, Franz Tamayo, La Paz, Bolivia in January 2004. Researchers observed that the rats stopped nursing on day 22 and began gnawing and looking for solid food. Findings indicated growth patterns with sigmoid curves characteristics for all mammal species and small vertebrates.

Neogale africana (Desmarest, 1818), Amazon Weasel, is a poorly known South American carnivore, with records from north-central Brazil to Ecuador and south to central Peru and central Brazil. Based on two videographic records, we report the presence of this species in Bolivia and document a new elevational record. Furthermore, our new record extends the species' distribution by 900 km from the nearest locality in Peru, and by 1500 km from the nearest Brazilian locality. Current gaps in its distribution are attributable to the low detectability and rarity of this mustelid. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]