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Urophonius granulatus group.
No full text40 p. : ill., map ; 26 cm.
"August 23, 2010."A systematic revision of the granulatus group of the bothriurid scorpion genus Urophonius Pocock, 1893 is presented. Urophonius pizarroi, n. sp., a new species from central Chile, is described. Urophonius granulatus Pocock, 1898, Urophonius somuncura Acosta, 2003, and Urophonius tregualemuensis Cekalovic, 1981, are redescribed using modern standards. The adult males of U. somuncura and U. tregualemuensis are described for the first time. A distribution map and key to the species of the granulatus group are provided, along with a discussion of their phenology
Giant bandicoot.
No full text41 p. : ill., map ; 26 cm.
"September 14, 2010."The giant bandicoot, Peroryctes broadbenti (Ramsay, 1879), is represented in museum collections by 23 specimens collected at 12 localities in the lowlands of the southeastern peninsula (the "Papuan Peninsula") of Papua New Guinea. Available data on P. broadbenti are reviewed, including its comparative anatomy and morphological variability, taxonomic relationships, geographic and elevational distribution, dietary and reproductive traits, and conservation status. Despite previous confusion between this species and P. raffrayana (Milne-Edwards, 1878), the two species are readily distinguished by a suite of external, cranial, and dental characters. Diagnostic characters are enumerated and illustrated, and comparisons drawn with other New Guinean bandicoots. Generic distinction of Peroryctes Thomas, 1906, in cranial morphology from other New Guinean bandicoots is also reviewed. A striking degree of sexual dimorphism is documented in both body size and dentition for P. broadbenti; these comparisons are set in context by a review of sexual dimorphism among bandicoots in general
New material of Erketu ellisoni.
No full text27 p. : ill. ; 26 cm.
"October 22, 2010."Phylogenetic relationships among the diverse Cretaceous sauropods of East Asia have long been controversial. Debate has centered on whether there is any evidence for an endemic clade of Asian species ("Euhelopodidae") and on the placement of these taxa within the context of higher sauropod phylogeny. While most Cretaceous sauropod taxa from Asia are recognized as part of Somphospondyli, recent discoveries have suggested Brachiosauridae may have dispersed into Asia as well. We present new fossils and analyses bearing on these issues. Additional material of the holotype individual of Erketu ellisoni recovered on a subsequent visit to the type locality expands the character data available for this unique sauropod. Associated sauropod dorsal and caudal vertebrae were collected from the same horizon, at a location approximately 2 km from the holotype excavation. The dorsal vertebra exhibits synapomorphies suggesting a representative of Titanosauria co-occurred with Erketu ellisoni. These new specimens, as well as recent discoveries of contemporary Asian sauropod taxa, allow a basis for phylogenetic reappraisal of Erketu and related taxa. Phylogenetic results support a sister group relationship between the Asian Cretaceous sauropods Erketu and Qiaowanlong. Although Qiaowanlong was described as a brachiosaurid, it joins Erketu on the somphospondylian side of the Brachiosauridae-Somphospondyli divergence, erasing the evidence for the dispersal of Brachiosauridae into Asia
A review of Microhydromys (Rodentia, Murinae), with description of a new species from southern New Guinea. (American Museum novitates, no. 3676)
No full text22 p. : ill. (some col.), map ; 26 cm.
"March 4, 2010."
Includes bibliographical references (p. 19-22).The murine rodent genus Microhydromys Tate and Archbold, 1941, includes the smallest of the native rodents of New Guinea and is the rarest Australo-Papuan rodent genus preserved in world museums. We discuss the morphological characteristics of Microhydromys and diagnose two species in the genus: M. richardsoni Tate and Archbold, 1941, distributed over northern New Guinea, and M. argenteus, n. sp., recorded from three localities in southern New Guinea. The only other species previously classified in the genus--Microhydromys musseri Flannery, 1989--is re-allocated to the genus Pseudohydromys Rümmler, 1934. The little available information relating to their biology indicates the species of Microhydromys to be terrestrial inhabitants of foothill and lower montane forest formations and probably naturally rare in those environments
New nonmammalian eucynodont.
No full text24, [1] p. : ill. (some col.), maps (some col.) ; 26 cm.
"June 25, 2010."
Includes bibliographical references (p. 19-21).A new trirachodontid eucynodont, Beishanodon youngi, is named and described based on a well-preserved skull from Triassic lacustrine deposits exposed in the Beishan Hills, northern Gansu Province, China. The new discovery documents the second record of trirachodontid eucynodonts known from China, along with Sinognathus gracilis from the Middle Triassic Ermaying Formation exposed in Shanxi Province. Cladistic analysis supports the placement of the new taxon as the sister group of Sinognathus, and the two together can be classified in Sinognathinae, a new subfamily differentiated from other trirachodontids by possession of several derived character states, including extremely short snout and strongly expanded temporal region. In addition, the stratigraphic and biogeographic significance of the new discovery are discussed. Because trirachodontids have a restricted stratigraphic range in the Triassic, as best documented by the Cynognathus Assemblage Zone of South Africa, discovery of the new fossil of this group from northern Gansu Province in China provides definitive evidence for a Triassic age of the fossil-bearing beds exposed in the Beishan Hills; moreover, the fossil beds are assessed as early Triassic in age based on the evidence from the entire vertebrate fauna
Craniodental materials of Litolophus gobiensis.
No full text26, [1] p. : ill. ; 26 cm.
"June 25, 2010."
Includes bibliographical references (p. 19-22).We describe new craniodental specimens of Litolophus gobiensis recently unearthed from the type locality of the genus, and conduct phylogenetic analyses of Eocene chalicotheres based on a data matrix containing 21 taxa and 58 craniodental characters. Although the phylogenetic relationships of the Eocene chalicotheres are not well resolved in the strict component consensus tree, the 50% majority rule consensus shows that two post-earliest Eocene chalicothere lineages are present. The first lineage represents the main line of chalicothere evolution, including "Grangeria" anarsius, Eomoropus, and post-Eocene chalicotheres. The second lineage, consisting of Litolophus gobiensis and Grangeria canina, is the sister group and stem member to the main lineage. The derivative strict reduced consensus tree, with three unstable taxa pruned, supports some tree topologies of the 50% majority consensus. The taxonomy of some chalicothere taxa is revised based on the phylogenetic analyses, such as "Grangeria" anarsius being probably better referred to the genus Eomoropus as originally identified, E. ulterior being the sister taxon to E. amarorum, and Lophiodon being excluded from the Ancylopoda but allied with the Ceratomorpha
Early Tertiary pseudotoothed birds.
No full text71 p. : ill., map ; 26 cm.
"December 20, 2010."We describe here new specimens of pseudotoothed birds (Odontopterygiformes) from the Upper Paleocene and Lower Eocene of the Ouled Abdoun Basin, Morocco. These Lower Paleogene fossils are among the oldest representatives of the Odontopterygiformes and include braincases, beak fragments, and long bones. Dasornis toliapica (Owen, 1873) (2-3 m wingspan) and Dasornis emuinus (Bowerbank, 1854) (3.5-4.5 m wingspan) were initially described from the Lower Eocene London Clay of Sheppey, England. The new species Dasornis abdoun (1.5-1.7 m wingspan) constitutes the smallest species of pseudotoothed bird ever discovered. We partly revise the oversplit taxonomy of the odontopterygiforms: the two species from the Paleogene of England and Morocco are regarded as congeneric, the name Dasornis having priority over the name Odontopteryx. We also synonymize Neptuniavis minor Harrison and Walker, 1977, and Macrodontopteryx oweni Harrison and Walker, 1976, with D. toliapica (Owen, 1873). Moreover, the genera Pelagornis Lartet, 1857, and Osteodontornis Howard, 1957, are regarded as pertaining to one single taxonomic entity that corresponds to the Pelagornis morphotype. In Dasornis, the morphological peculiarities of the humerus that are related to gliding flight are less pronounced than in Pelagornis. The latter taxon includes exceedingly specialized gliders that were most likely unable of sustained flapping flight and relied almost entirely on winds to provide lift. Pseudotoothed birds pertaining to the Dasornis morphotype were more generalists and could probably undertake flapping flight, even if limited. The species of Dasornis were soaring pelagic feeders that could disperse over large territories like extant albatrosses. They formed large breeding colonies near the shore of the northeastern part of the Moroccan phosphate sea, some 55 million years ago. Our work provides evidence that Dasornis was widespread in the early Tertiary, as it is currently known from the Lower Paleogene deposits of Morocco, England, and Kazakhstan. Paleoenvironmental studies show that these marine deposits formed in a tropical climate. This could explain the occurrence of both Dasornis and prophaethontids in all three Paleogene localities
Extant and extinct artiodactylans.
No full text206 p. : ill. ; 26 cm.
"Issued June 3, 2010."
Includes bibliographical references (p. 202-206).I describe and figure petrosal bones for a sample of 35 (12 extinct, 23 extant) artiodactylans, perissodactylans, †mesonychids, and archaic ungulates. Detailed herein are the cladistic characters of the petrosal used in the recent combined analysis of molecular and morphological data by Spaulding et al. (2009). That analysis, the largest in taxa and characters for artiodactylans (including cetaceans) to date, showed that hippopotamids are the closest living relatives of cetaceans. It also showed that in the shortest trees †Indohyus is on the stem lineage to Cetacea and that †mesonychians are positioned outside Artiodactyla; however, these positions for fossils are highly unstable, as †mesonychians are more closely related to cetaceans than is †Indohyus in trees only two steps longer. I show that in many ways the osteology of the hippopotamid ear resembles that of certain stem cetaceamorphans more than it resembles the ear regions of suines (pigs and peccaries). Previous studies have suggested that many artiodactylans lacked an inflated tegmen tympani of the petrosal; however, that generalization is not supported by data presented herein. Petrosal characters, such as the presence of the prefacial commissure fossa, presence of a convex and hyperinflated tegmen tympani, and the absence of a subarcuate fossa, are shown to be synapomorphies of hippopotamids and cetaceans. Some of these features were previously argued to represent a special similarity between †mesonychids and cetaceans, but these are here interpreted as homoplasies. Other features previously argued to be extremely similar between †mesonychians and cetaceans to the exclusion of other ungulates, such as the presence of the anterior process of the tegmen tympani, are shown to be more widely distributed among ungulates than previously recognized. A number of artiodactylans, including ruminants, are also shown to have transpromontorial sulci on the petrosal despite reports that the internal carotid artery is absent in the neck of ruminants. The petrosals of †anthracothere and †entelodont species exhibit varied morphology, with the †anthracothere †Bothriogenys having the greatest gross similarity to the hippopotamid and cetaceamorphan condition; however, shortest trees indicate that these similarities are convergent