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Kinkonychelys, a new side-necked turtle (Pelomedusoides, Bothremydidae) from the late Cretaceous of Madagascar. (American Museum novitates, no. 3662)
No full text25 p. : ill., 1 map ; 26 cm.
"August 28, 2009."
Includes bibliographical references (p. 23-25).The type specimen of Kinkonychelys rogersi, n. gen. et sp., is the first turtle skull to be described from the pre-Holocene fossil record of Madagascar. This specimen, a nearly complete cranium, along with several referred specimens (a series of maxillae and a partial lower jaw), was recovered from the Maastrichtian Maevarano Formation in the Mahajanga Basin of northwestern Madagascar. A braincase with the diagnostic characters of Kinkonychelys, but differing in the position of the jaw articulation, formation of the foramen nervi facialis, and a number of other characters, was found in the same rock unit and is provisionally identified as belonging to Kinkonychelys sp., a presumed distinct, but closely related species, too incomplete to be diagnosed at present. Kinkonychelys is a bothremydid because it has the diagnostic characters of an exoccipitalquadrate contact and a fully enclosed incisura columellae auris (Gaffney et al., 2006). Kinkonychelys belongs to the tribe Kurmademydini, previously known to include only Sankuchemys and Kurmademys from the late Cretaceous of India, because it has a deep fossa pterygoidea, a foramen stapediotemporale facing dorsally, a jugal not retracted from the orbit, a deep fossa precolumellaris, and a large, wide antrum postoticum. Kinkonychelys rogersi and Kinkonychelys sp. both possess a unique form of the overlapping fossa pterygoidea. A cladistic analysis of Kinkonychelys reveals that it is nested within the tribe Kurmademydini of Gaffney et al. (2006) and is related to the other taxa in the tribe as follows: (Sankuchemys (Kinkonychelys+Kurmademys)). The discovery of a Malagasy bothremydid of Maastrichtian age that is nested within the Indian members of the Kurmademydini supports the hypothesis of a connection between Madagascar and the Indian subcontinent that persisted into the late stages of the late Cretaceous
Behavior of Biastes emarginatus.
No full text15 p. : ill. ; 26 cm.
"November 30, 2009."
Includes bibliographical references (p. 14-15).We present information on the nest-searching and parasitic behavior of the European cleptoparasitic bee Biastes emarginatus (Schenck), found attacking nests of Rophites quinquespinosus Spinola in the Czech Republic. Its mature oocyte, first instar, and last larval instar are described and illustrated by SEM micrographs, microphotographs, and diagrams. These stages are compared with those of other members of the Biastini. Because the first instar of the related Neopasites cressoni had not been described before, its description is appended, so that comparisons can be made with B. emarginatus. In most respects, the biology and immature stages of B. emarginatus closely resemble what is known concerning other tribal members, but we note that the mature larva, though agreeing morphologically with those of close relatives, has an anatomy that invites investigation into adaptive function
A new genus of microteiid lizard from the Caparaó Mountains, southeastern Brazil, with a discussion of relationships among Gymnophthalminae (Squamata). (American Museum novitates, no. 3673)
No full text27 p. : ill., 1 map ; 26 cm.
"November 30, 2009."
Includes bibliographical references (p. 20-22).A new genus and species of microteiid lizard is described based on a series of specimens obtained at Parque Nacional do Caparaó (20°28'S, 41°49'W), southeastern Brazil, along the division line between the States of Minas Gerais and Espírito Santo. The new lizard occurs in isolated high-altitude, open, rocky habitats above the altitudinal limits of the Atlantic forest. It is characterized by the presence of prefrontals, frontoparietals, parietals, interparietal, and occipital scales; ear opening and eyelid distinct; three pairs of genials; absence of collar; lanceolate and mucronate dorsal scales; six regular transverse and longitudinal series of smooth ventrals that are longer than wide, with the lateral ones narrower. Maximum parsimony (MP) and partitioned Bayesian (PBA) phylogenetic analyses based on morphological and molecular characters with all known genera of Gymnophthalminae (except for Scriptosaura) plus Rhachisaurus recovered this new lizard in a clade having Colobodactylus and Heterodactylus as its closest relatives. Both analyses recovered the monophyly of Gymnophthalminae and Gymnophthalmini. The monophyly of the Heterodactylini received moderate support in MP analyses but was not recovered in PBA. To eliminate classification controversy between these results, the present concept of Heterodactylini is restricted to accommodate the new genus, Colobodactylus and Heterodactylus, and a new tribe Iphisiini is proposed to allocate Alexandresaurus, Iphisa, Colobosaura, Acratosaura, and Stenolepis. Current phylogenetic knowledge of Gymnophthalminae suggests that fossoriality and increase of body elongation arose as adaptive responses to avoid extreme surface temperatures, either cold or hot, depending on circumstances
Shamosuchus and eusuchian origins.
No full text103 p. : ill. (2 col.), col. map ; 26 cm.
"Issued June 30, 2009."
Includes bibliographical references (p. 79-86).We describe a new specimen of the fossil crocodyliform taxon Shamosuchus djadochtaensis from the late Cretaceous Djadokhta Formation. The new specimen consists of an almost complete skull found in association with postcranial material. Because it is considerably more complete than the holotype, the new specimen permits proper diagnosis of Shamosuchus djadochtaensis and offers new information for exploring its phylogenetic relationships. The phylogenetic analysis conducted here improves taxon sampling of neosuchian crocodyliforms with respect to previous approaches to crocodyliform systematics and reveals that Shamosuchus djadochtaensis bears important information toward an understanding of the relationships of advanced neosuchians and the evolutionary origin of Eusuchia. Shamosuchus djadochtaensis is found to be the sister group of Rugosuchus nonganensis, comprising an Asian clade diagnosed by the presence of a sagittal ridge on the dorsal surface of the frontal, confluent openings for the exit of cranial nerves IX-XI, a posterior region of the palatine bar between suborbital fenestra that is flared posteriorly, and a longitudinal ridge on the lateral surface of the angular. This clade is inferred to be the sister group of Eusuchia, to the exclusion of Bernissartia fagesii and the Glen Rose form, based on the absence of an acute anterior tip of the frontal that wedges between the nasals, the presence of rodlike neural spines in the posterior cervical vertebrae, procoelous cervical vertebrae, and the presence of hypapophyses in the three anteriormost dorsal vertebrae. Incorporating the new information into the phylogenetic analysis indicates the decoupled nature of the evolutionary history of procoely in different regions of the vertebral column and the eusuchian type of palate, both traditionally considered as diagnostic of Eusuchia. All these features have complex evolutionary histories with several cases of convergences and reversals. Finally, a review of all the available evidence on the diversity of advanced neosuchians suggests this group achieved a worldwide distribution and a remarkable morphological diversity, pushing their evolutionary origins back to the Jurassic.American Museum of Natural History
Two new Miniopterus from Madagascar.
No full text34 p. : ill. (some col.), 1 map ; 26 cm.
"November 30, 2009."
Includes bibliographical references (p. 31-34).Based on nearly complete (1125 bp) cytochrome-b sequence data and morphological characters, two new endemic species of Miniopterus are described from Madagascar that were previously identified as M. manavi. Using phylogenetic analysis, the basal nodes of major lineages in the Malagasy members of this genus are weakly supported, while, in most cases, the branches leading to each of the clades are well resolved. Miniopterus mahafaliensis, new species, occurs in the southwestern semidesert areas and M. brachytragos, new species, has a broad distribution across the northern half of the island, ranging across several different biomes. Phylogenetic inference indicates that these two new taxa are not closely related to M. manavi sensu stricto, with average genetic distances of 9.2% and 5.7% from this taxon, respectively. On the basis of this and previous revisions, the former M. manavi complex is now recognized to represent at least five taxa, which do not form a monophyletic group with respect to one another, and represent extraordinary examples of convergent evolution. Miniopterus brachytragos is closely related to the recently named M. aelleni, while M. mahafaliensis is not closely associated with any of these species. Molecular phylogenetic analysis was imperative to resolve the species limits of these taxa and morphology then provided the means to corroborate the recovered clades. There are localities on the island, specifically limestone karstic zones, where four species of the former M. manavi sensu lato complex occur in strict sympatry. These species often use the same day-roost caves and have similar external and craniodental measurements. This raises intriguing questions as to how these animals divide their worlds with regard to dietary regimes and foraging strategies, as well as their speciation history
New Guinea Coccymys and "Melomys" albidens.
No full text139 p. : ill. (some col.), maps ; 26 cm.
"Issued December 9, 2009."
Some specimens of Coccymys collected during the fourth Archbold Expedition to New Guinea (1953).
Includes bibliographical references (p. 135-139).A new species of the New Guinea endemic murine genus Coccymys is described, based on a small sample from Mt. Dayman and Mt. Simpson in the Maneau Range at the far eastern end of the Owen Stanley Ranges of eastern Papua New Guinea, and two specimens from the western portion of the Owen Stanleys, one from Smith’s Gap near Mt. St. Mary, the other from Bulldog Road in the Wau area. Coccymys kirrhos, n. sp., is a vicariant relative of C. shawmayeri, which occurs in the Central Cordillera of Papua New Guinea extending from Mt. St. Mary in the east to the Telefomin region in the west. Coccymys shawmayeri in turn is the eastern montane vicariant of the western New Guinea C. ruemmleri, so far recorded only from the Snow Mountains in western New Guinea (Papua Province of Indonesia) and the eastern end of the Star Mountains over the border in the western section of Papua New Guinea. Coccymys ruemmleri and C. shawmayeri are regionally sympatric in western Papua New Guinea where the former is apparently restricted to high altitudes on the Star Mountains and the latter occurs at lower altitudes in the highlands bounding the Telefomin Valley. The ranges of C. shawmayeri and C. kirrhos, n. sp., overlap at the western section of the Owen Stanley Ranges, and both species have been caught at Bulldog Road, but in different years. This linearly distributed trio of species has been found only in the montane forests and alpine grasslands of the Central Cordillera--there are no records from mountains on Vogelkop Peninsula and the Huon Peninsula, nor from any of the north coast ranges. The new species is described within the context of rediagnosing the genus Coccymys, and documenting morphometric and geographic limits of C. ruemmleri and C. shawmayeri based on most specimens stored in collections of museums. This material consists primarily of museum study skins and accompanying skulls, some fluid-preserved specimens, skeletal fragments from modern samples of owl pellets, and Holocene and late Pleistocene fossils (for C. ruemmleri only). All species of Coccymys are nocturnal and scansorial; stomach contents from samples of C. shawmayeri indicate the diet consists of seeds, fruit, and arthropods. The taxon albidens is represented by six modern examples collected at 2800 m and 3225 m in 1938 from the northern slopes of the Snow Mountains of western New Guinea, and three late Pleistocene fossils obtained from the same region. The species was initially described as a Melomys (Tate, 1951); later an alliance with Coccymys was suggested (Flannery, 1990; Menzies, 1990; Musser and Carleton, 1993), but restudy of anatomical traits (derived solely from stuffed skins with accompany[y]ing skulls) reveals a degree of morphological divergence not only from species in Coccymys but from any other "Old Endemic" New Guinea murine. A new genus, Brassomys, sampled by only six modern specimens and three late Pleistocene fossils, is proposed to embrace albidens. Morphological attributes of that species are contrasted primarily with those characterizing Coccymys, and secondarily with the genera Melomys, Paramelomys, Mammelomys, Protochromys, Abeomelomys, and Pogonomelomys. Biological aspects of albidens are unknown; however, particular external, cranial, and dental traits in combination strongly suggest the species is a nocturnal, arboreal/scansorial invertebrate predator
Contributions in honor of Guy G. Musser.
No full text450 p. : ill. (some col.), maps ; 26 cm.
"Issued December 15, 2009."
Includes bibliographical references.Contents: They sort out like nuts and bolts : a scientific biography of Guy G. Musser / Michael D. Carleton -- Taxonomy, distribution, and natural history of the genus Heteromys (Rodentia: Heteromyidae) in central and eastern Venezuela, with the description of a new species from the Cordillera de la Costa / Robert P. Anderson and Eliécer E. Gutiérrez -- Review of the Oryzomys couesi complex (Rodentia: Cricetidae: Sigmodontinae) in western Mexico / Michael D. Carleton and Joaquin Arroyo-Cabrales -- The antiquity of Rhizomys and independent acquisition of fossorial traits in subterranean muroids / Lawrence J. Flynn -- A new species of Reithrodontomys, subgenus Aporodon (Cricetidae: Neotominae), from the highlands of Costa Rica, with comments on Costa Rican and Panamanian Reithrodontomys / Alfred L. Gardner and Michael D. Carleton -- Phylogenetic relationships of harpyionycterine megabats (Chiroptera: Pteropodidae) / Norberto P. Giannini, Francisca Cunha Almeida, and Nancy B. Simmons -- A new genus and species of small "tree-mouse" (Rodentia, Muridae) related to the Philippine giant cloud rats / Lawrence R. Heaney, Danilo S. Balete, Eric A. Rickart, M. Josefa Veluz, and Sharon A. Jansa -- Biodiversity and biogeography of the moss-mice of New Guinea : a taxonomic revision of Pseudohydromys (Muridae: Murinae) / Kristofer M. Helgen and Lauren E. Helgen -- Systematic revision of sub-Saharan African dormice (Rodentia: Gliridae). Part 2, Description of a new species of Graphiurus from the central Congo Basin, including morphological and ecological niche comparisons with G. crassicaudatus and G. lorraineus / Mary Ellen Holden and Rebecca S. Levine -- Descriptions of new species of Crocidura (Soricomorpha: Soricidae) from mainland Southeast Asia, with synopses of previously described species and remarks on biogeography / Paulina D. Jenkins, Darrin P. Lunde, and Clive B. Moncrieff -- The six opossums of Félix de Azara : identification, taxonomic history, neotype designations, and nomenclatural recommendations / Robert S. Voss, Philip Myers, François Catzeflis, Ana Paula Carmignotto, and Josefina Barreiro -- Skull and dentition of Willeumys korthi, nov. gen. et sp., a cricetid rodent from the Oligocene (Orellan) of Wyoming / John H. Wahlert
Postcranial morphology of didelphid marsupials.
No full text175 p. : ill. ; 26 cm.
Issued March 17, 2009.
Includes bibliographical references (p. 69-73).In this study I provide a phylogenetic hypothesis for didelphid Marsupials including a suite of 114 postcranial characters. The postcranial evidence was cladistically analyzed separately and concatenated with a nonmolecular data set previously published (71 cranio-dental-external characters). A combined analysis was done including published IRBP (interphotoreceptor retinoid binding protein, 1158 bp), DMP-1 (dentin matrix protein 1, 1176 bp), and RAG-1 (recombinase-activating gene, 2790 bp) sequences to the nonmolecular data set. In order to compare and evaluate the influence of the inclusion of postcranial morphology to previous hypotheses, the taxon sampling of didelphine ingroups was almost similar to the one used in recent series of papers on didelphid phylogeny. The postcranial information includes 48 characters from the axial skeleton, 37 from the anterior limb, and 29 from the posterior limb. I present anatomical descriptions for each postcranial character, adding details of different conditions observed among didelphine ingroups, as well as some functional implications. Different hypotheses that are discussed as polymorphic characters are alternatively treated as composite entries (CO) and transformation series (TS) in morphological and combined analyses. Different codings of polymorphic postcranial characters produce topologies that in general are not contradictory. The principal difference is the loss of resolution of trees in TS analysis, compared to CO analysis in postcranial evidence, whereas the support values were in general low in both codings. The topology obtained from postcranial evidence supported some already recovered relationships, such as the monophyly of the large opossums (Didelphis, Philander, Chironectes, Lutreolina, and Metachirus), and several polytypic groups such as Didelphis, Monodelphis, Marmosops, Thylamys, Micoureus, and Philander. Additionally, the intermediate position of Hyladelphys between calorumyines and didelphines is kept in CO analysis. The inclusion of the postcranial data set to previous nonmolecular evidence causes little incongruence, although some modifications in the topology and support values were detected. The effect of different codings of polymorphic characters was similar respect to the postcranial-only data set. In this case, the topology obtained with CO analysis was also notably better resolved than TS analysis. Similarly to the postcranial-only analysis, the topologies obtained in the total morphological evidence applying the two kinds of codings are highly congruent, but the TS treatment seemed not to contribute to retention of more phylogenetic information, since the CO analysis was better resolved. The relationships obtained adding the postcranial evidence to published combined data set (i.e., morphology, IRBP, DMP-1, and RAG-1 sequences) were mostly better resolved and supported in the CO coding than the morphological analyses, although the TS coding causes loss of resolution in the strict consensus. In this sense, some strong differences on deep branch topology can be detected depending on the treatment applied to polymorphic entries and partitioned analyses (e.g., phylogenetic condition of the mouse opossums, nodes C and B). Including the postcranial evidence in the total data set, I also recovered the intermediate position of Hyladelphys, but never the distantly related clades recently recovered by the inclusion of RAG-1 sequences (clades B + I in Gruber, K.F., R.S. Voss, and S.A. Jansa. 2007. Base-compositional heterogeneity in the RAG1 locus among didelphid marsupials: implications for phylogenetic inference and the evolution of GC content. Systematic Biology 56: 1-14). However, the position of Metachirus and Tlacuatzin canescens is highly affected. Excluding the last gene, the partitioned combined analysis considering postcranial evidence was highly congruent with previous IRBP, morphology, and combined topologies, especially in the TS analysis, where all already defined nodes were recovered. The inclusion of postcranial evidence to the previous combined data set actually improves the support values when RAG-1 is eliminated. However, even when the topologies from both kinds of codings of polymorphic data were considerably congruent, the mouse opossums were clustered in CO analysis (although including Metachirus if RAG-1 sequences are included). The application of different criteria for the treatment of polymorphic data affects the relationships and phyletic condition of the mouse opossums. Finally, I discuss the postcranial morphology as evidence of didelphid phylogeny, as well as the new postcranial synapomorphies found in the monophyletic groups recovered in the didelphid crown group
Eocene mammals from western Patagonia.
No full text43 p. : ill., map ; 26 cm.
"March 31, 2009."
Includes bibliographical references (p. 38-43).Two new fossil mammal localities from the Paleogene of central-western Patagonia are preliminarily described as the basis for a new possible biochronological unit for the early Eocene of Patagonia, correlated as being between two conventional SALMAs, the Riochican (older) and the Vacan subage of the Casamayoran SALMA. The mammal-bearing strata belong to the Middle Chubut River Volcanic-Pyroclastic Complex (northwestern Chubut Province, Argentina), of Paleocene-Eocene age. This complex includes a variety of volcaniclastic, intrusive, pyroclastic, and extrusive rocks deposited after the K-T boundary. Geochronological data taken from nearby volcanic deposits that underlie and overlie the mammal-bearing levels indicate that both faunas are of late early Eocene age (Ypresian-Lutetian boundary). In addition to more than 50 species of mammals, including marsupials, ungulates, and xenarthrans, two lower molars are the oldest evidence of bats in South America. Paleobotanical and palynological evidence from inferred contemporary localities nearby indicate subtropical environments characterized by warm and probably moderately humid climate. Remarkably, this new fauna is tentatively correlated with Eocene mammals from the La Meseta Formation in the Antarctic Peninsula. We conclude that the two localities mentioned above are part of a possible new biochronological unit, but the formal proposal of a new SALMA awaits completion of taxonomic analysis of the materials reported upon here. If the La Meseta fauna is correlated biochronologically to western Patagonia, this also suggests a continental extension of the biogeographic Weddelian Province as far north as central-western Patagonia.Published by the American Museum of Natural History, New York, NY
Caninemys, Miocene side-necked turtle.
No full text26 p. : ill., map ; 26 cm.
"March 31, 2009."
Includes bibliographical references (p. 21-23).A new genus and species of podocnemidid pleurodire, Caninemys tridentata, is described on the basis of a skull collected by L.I. Price in 1962 from the late Miocene of Acre, Brazil. It is unique among podocnemidids (and all other turtles) in having greatly inflated maxillae, each with a ventral, toothlike process. Along with a midline process of the premaxillae, these processes form a tridentate condition in the upper triturating surface, also unique among podocnemidids but comparable to the condition in the kinosternid Claudius. This skull has previously been identified as the shell-based genus Stupendemys, but there are no associations supporting this assignment. The type specimens are separated by over 2000 km, and other large podocnemidid taxa are known from this time and region. Although relatively large with a condylobasal skull length of about 17 cm, Caninemys was probably about half the size of Stupendemys. Phylogenetic analysis of 63 skeletal characters provides evidence that this new taxon nests within the family Podocnemididae as follows: (Bauruemys (“Roxochelys” (Podocnemis (Caninemys (Dacquemys ((Erymnochelys, Peltocephalus) (Neochelys (Shweboemys, Stereogenys)))))))).Published by the American Museum of Natural History, New York, NY