Search

We describe a new species of Rattus , from 3 modern specimens collected on Manus Island in the Admiralty Group, Papua New Guinea, between 2002 and 2012. Subfossil specimens of early to late Holocene age from the Pamwak archaeological site on Manus Island are referred to the new species on morphological criteria; these confirm the species as a long-term resident of Manus Island. The new species is distinguished by its combination of large size; short tail; dorsal pelage that is coarse, spiny, and dark, with prominent black guard hairs; and sharply contrasting cream ventral pelage. Based on its overall body form, the species is almost certainly terrestrial. The dentition combines robust incisors with relatively small molars and the cranium displays a distinctive melange of characters—including an elongate and anteriorly expanded rostrum and a mesopterygoid fossa that is narrow anteriorly and broadens to the rear. Sequence data from the mitochondrial control region and 3 nuclear genes place the new species as a highly divergent member of the Australo–Papuan Rattus radiation, with no identified close relative among sampled taxa. Morphological comparisons are made between the new species and other pertinent species of Rattus from the region, including R. sanila , a species known only from Late Pleistocene fossil to Late Holocene subfossil remains from an archaeological site on New Ireland. The conservation status of the new species is discussed in the light of a recent survey that failed to locate surviving populations in 2 areas of natural forest on Manus Island. Further survey work is urgently needed to identify any surviving populations and to assess the role of potential threats to the species.

We document for the first time that Sciurus ignitus, a medium-sized agouti-patterned squirrel with white venter, occurs in Paraguay, being found in the northern Chaco–Pantanal region of the country, where the borders of Paraguay, Bolivia, and Brazil come together. Sciurus urucumus, the only species of squirrel previously known with certainty to range into Paraguay, occurs in the Chiquitano Forest of the northeastern Paraguayan Chaco. We provide details of the Paraguayan habitats for the known specimens of both species. At present, we know of no localities where the two species co-occur. We critically evaluate some of the morphological characters used previously to characterize S. ignitus. Interviews with local hunters, including Ache indigenous ones, coupled with an earlier published account, indicate that the squirrel Sciurus aestuans also occurs in eastern Paraguay's Departamento Alto Parana, although no specimens are now available from the country.

By means of mitochondrial 12S rRNA sequencing of putative “yeti”, “bigfoot”, and other “anomalous primate” hair samples, a recent study concluded that two samples, presented as from the Himalayas, do not belong to an “anomalous primate”, but to an unknown, anomalous type of ursid. That is, that they match 12S rRNA sequences of a fossil Polar Bear (Ursus maritimus), but neither of modern Polar Bears, nor of Brown Bears (Ursus arctos), the closest relative of Polar Bears, and one that occurs today in the Himalayas. We have undertaken direct comparison of sequences; replication of the original comparative study; inference of phylogenetic relationships of the two samples with respect to those from all extant species of Ursidae (except for the Giant Panda, Ailuropoda melanoleuca) and two extinct Pleistocene species; and application of a non-tree-based population aggregation approach for species diagnosis and identification. Our results demonstrate that the very short fragment of the 12S rRNA gene sequenced by Sykes et al. is not sufficiently informative to support the hypotheses provided by these authors with respect to the taxonomic identity of the individuals from which these sequences were obtained. We have concluded that there is no reason to believe that the two samples came from anything other than Brown Bears. These analyses afforded an opportunity to test the monophyly of morphologically defined species and to comment on both their phylogenetic relationships and future efforts necessary to advance our understanding of ursid systematics.

We expand upon recent studies on relationships within the Oryzomyini, in particular, those involving taxa currently assigned to the genus Sigmodontomys. In recent years, Sigmodontomys has been treated as including 2 species, alfari (J. A. Allen, 1897) and aphrastus (Harris, 1932), but throughout their complicated taxonomic history both species also have been placed in the genus Oryzomys, and alfari independently in Nectomys. Using morphological (98 external, cranial, dental, and postcranial) and molecular (nuclear interphotoreceptor retinoid–binding protein gene and mitochondrial cytochrome-b and ribosomal 12S RNA genes) characters, we infer the phylogenetic position of these 2 species within Oryzomyini. We document that alfari and aphrastus do not form a monophyletic group. Sigmodontomys alfari is most closely related to Melanomys, and aphrastus is either the sister to that clade, or to the extinct Caribbean genus Megalomys. Thus, aphrastus is best regarded as representing a new genus, which is ...

A new species of the didelphid marsupial genus Monodelphis is described from the eastern Bolivian province of Santa Cruz. The new species, currently known from a single specimen, belongs to the M. brevicaudata group but differs from other taxa within that clade (M. brevicaudata, M. domestica, M. glirina, M. maraxina, and M. palliolata) in size, qualitative morphological characters, and cytochrome-b gene sequences.

Until now, there has been a single Paraguayan record of climbing rats of the genus Rhipidomys (Tschudi, 1845), and the specimen has not been identified at the species level. Remarkably, this record has been overlooked in recent mammal lists. Field work conducted in Paraguay during and since 2006 has produced the second and third records of Rhipidomys for this country. We conducted an assessment of external and skull morphologic variation, as well as Maximum Parsimony and Bayesian analyses based on DNA sequences, all of which indicate that all three known Paraguayan specimens of Rhipidomys belong to the species Rhipidomys macrurus (Gervais, 1855). In addition, we provide information distinguishing R. macrurus from some of its congeners, as well as new natural history data. There is now a total of 31 sigmodontine species with published Paraguayan records.

Mouse opossums of the genus Marmosa Gray (Didelphidae) represent a complex of taxa with poorly understood affinities. Species now placed within this genus are mostly the leftovers from previous taxonomic arrangements. Even the most recent and complete revisions have not fully resolved the relationships among Marmosa and the many taxa previously included in Marmosa or listed as synonyms of it. Herein, we review and discuss one of these taxa, Stegomarmosa, based on new specimens that significantly increase our knowledge of the morphological diversification of the group. Until recently, this genus/subgenus has been known only from a single specimen taken more than 50 years ago in southeastern Peru. In 1997-1998, six additional specimens were collected at two little-separated localities almost 200 km NW of the type locality. We include a detailed diagnosis of the genus-group Stegomarmosa and its type species, M. andersoni, and update the distribution for and provide new information on the natural history of the latter. We also discuss published claims, concerning geographic range, that may be inaccurate and misleading. Finally, we scored the morphological characters used in the most recent phylogenetic analyses of the didelphids, in order to explore the affinities of M. andersoni and to determine the distinctiveness of the taxon Stegomarmosa.

Eruption sequences of permanent cheek teeth in various insectivores and carnivores were ascertained. The Insectivora shows relatively great variation in eruption sequences, reflecting the heterogeneity of the order. In the Canidae, Hyaenidae, and Felidae the fourth premolars generally complete eruption before the third premolars. In Mustelidae and Viverridae the lower third premolar completes eruption before the lower fourth premolar. The functional and evolutionary significances of this and other differences in sequence between taxa are discussed.

A new subgenus of Marmosa and its type species are described from Peru. Morphological characters separating the new subgenus from currently recognized subgenera of murine opossums are presented. Characters separating the new species from other species of Marmosa found to be sympatric with it are also discussed.

Twenty-seven species of bats which are rare in collections and/or which constitute noteworthy records of range extension are discussed. Two are new to Mexico: 8 to Chiapas, 3 to Veracruz, 4 to Honduras, 6 to Nicaragua, one to Panama, 2 to Guatemala. The systematic status of Sturnira mordax (Goodwin) is discussed. Weights, measurements and biological data are included for most species.

The taxonomy and natural history of the long-whiskered rice rat, Oryzomys bombycinus Goldman, is reviewed. This species, known previously from a few localities in Costa Rica, Panama, and Colombia is here definitely reported for the first time from Nicaragua and Ecuador. The currently recognized subspecies are provisionally retained on the basis of coat color. Habitat preferences and other ecological information are discussed.

Monodelphis emihae (Thomas) generalement considere comme conspecifique avec M. brevicaudata (Erxleben), est une espece distincte sympatrique de M. brevicaudata. D'abord connu seulement de la rive occidentale de Rio Tapagos, M. emiliae existe aussi sur la rive orientale et au Perou. M. emiliae presente comme certains autres didelphides une coloration fugitive qui est en correlation avec sa fluorescence en lumiere ultraviolette

Evidence from morphological and behavioral investigations shows that the genus Brachyphylla, presently referred to the subfamily Stenoderminae, is more properly regarded as a phyllonycterine. Certain aspects of the natural history of Cuban phyllonycterines are discussed.

Until more comparisons can be made between bats of the subfamily Nyctophilinae, it seems premature to raise Bauerus (a subgenus of Antrozous ) to generic rank. In particular, complete specimens of Antrozous koopmani are needed. Two specimens of Bauerus taken recently in Honduras extend the known geographic range of the subgenus, which previously was known from one locality on the Tres Marias Islands and another in Veracruz. Antrozous (Bauerus) dubiaquercus and the nominal species A . ( B .) meyeri are treated as merely subspecifically distinct, with the former known only from the tropical deciduous forest of the Tres Marias Islands and the latter characteristic of the tropical evergreen forest of the mainland. The penes of A. dubiaquercus and A. pallidus are unusual, trilobate structures, different from those found in other North American vespertilionid bats and the Australian genus, Nyctophilus . Antrozous seems most closely related to the Old World Otonycteris , and neither seems closely related to the nyctophilines ( Lamingtona, Nyctophilus , and Pharotis ) of the Australian Region.