Ronald H. Pine

A newly recognized clade of trans-Andean Oryzomyini (Rodentia: Cricetidae), with description of a new genus.

Abstract 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 described and named herein. This new genus falls within the Sigmodontomys–Melanomys–Aegialomys–Nesoryzomys clade, which forms a monophyletic group of mainly southern Central American and northern South American taxa primarily restricted to lowland to midelevation montane trans-Andean habitats and possessing a marked ability to cross expanses of salt water. The new genus occurs at middle elevations from north-central Costa Rica to northwestern Ecuador and along with some populations of Aegialomys and Melanomys occupies the highest elevations for members of this group.

Specimen collection crucial to taxonomy

In their Letter “Photos belong in the taxonomic Code ” (24 February, p. [805][1]), A. R. S. Garraffoni and A. V. L. Freitas argued that, due to the problem posed by organisms whose diagnostic characteristics quickly deteriorate after specimen preservation, a revised version of the International

A new species of Rattus (Rodentia: Muridae) from Manus Island, Papua New Guinea

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 mé;lange 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.

No need to replace an “anomalous” primate (Primates) with an “anomalous” bear (Carnivora, Ursidae)

Abstract 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.

What is an ‘extant’ type specimen? Problems arising from naming mammalian species‐group taxa without preserved types

The International Code of Zoological Nomenclature allows the naming of new species without a type specimen ever having been preserved. This practice causes problems and is undesirable because if related, cryptic, sibling species are encountered later, it may not be possible either to allocate them with certainty to the earlier named species, or to determine them to be something different. We hypothesised that examination of the instances in which mammalian species were named without preserved types would reveal certain problems that are not unique to them, but are encountered more frequently than when types are preserved. We also thought the Codes stipulation that preserved types are not required in the case of specimens that are no longer ‘extant’ would present special problems hitherto unremarked upon in the literature. We conducted a review of cases involving putative new species of mammal named since 1900. These were analysed to see what special problems they present and the frequency of such problems. We found that the Codes waiver of the requirement that a type specimen be deposited in a collection if the specimen is no longer extant presents numerous problems—in particular, that a living-at-large type specimen can still be ‘extant’ even if its whereabouts are unknown at certain times and/or it may no longer be alive. Illustrations alone being used to designate type specimens is especially problematic, owing to mammals’ lack of meristic and other obvious distinguishing external characters. Hoaxes, the difficulty in determining that they are hoaxes, and various errors of taxonomic allocation appear to be especially common with names without preserved types. The Code should be revised to require preserved specimens as types for new names. Tissue samples alone for DNA analysis are not ideal for serving this purpose, but should be allowed to meet the requirement.

Distribution and ecology of squirrels (Rodentia: Sciuridae) in Paraguay, with first country records for Sciurus ignitus

Abstract 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 Aché indigenous ones, coupled with an earlier published account, indicate that the squirrel Sciurus aestuans also occurs in eastern Paraguays Departamento Alto Paraná, although no specimens are now available from the country.