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Early Cretaceous anuran from China.
No full text39 pages : illustrations (some color), map ; 26 cm.Based on 12 well-preserved skeletons of postmetamorphic individuals, a new crown-group frog taxon is named and described from the Lower Cretaceous Guanghua (upper part of Longjiang) Formation (stratigraphic equivalent of the world-famed Yixian Formation) exposed in Dayangshu Basin, Hulunbuir, in the far northeast of Inner Mongolia, China. The new taxon, Genibatrachus baoshanensis, documents another early Cretaceous anuran having reduction of the presacral vertebrae to eight in number, similar to several frog taxa of roughly the same age from Spain and Brazil. The new frog also displays several features that are ontogenetically and phylogenetically informative, including ontogenetic fusion of the palatine to the sphenethmoid, and ontogenetic fusion of ribs to the diapophyses of the posterior trunk vertebrae. In addition, the new discovery extends the geographic range of early Cretaceous frogs of the Jehol Biota northward to near the 50th parallel north in East Asia
Ordovician succession, Hinlopenstretet.
Get PDF28 pages : illustrations (some color), map ; 26 cm.The Ordovician sections along the western shore of the Hinlopen Strait, Ny Friesland, Spitsbergen were discovered in the late 1960s and since then prompted numerous paleontological publications; several of these publications are now considered classical in the literature of paleontology of Ordovician trilobites and of Ordovician paleogeography and stratigraphy. Our 2016 expedition aimed at a major recollection and reappraisal of these classical sites. Here we provide a first high-resolution lithological description of the Kirtonryggen and Valhallfonna formations (Tremadocian-Darriwilian), which together comprise a thickness of 843 m, a revised bio- and lithostratigraphy, and an interpretation of the depositional sequences. We find that the sedimentary succession is very similar to successions of eastern Laurentia; its Tremadocian and early Floian part is composed of predominantly peritidal dolostones and limestones characterized by ribbon carbonates, intraclastic conglomerates, microbial laminites, and stromatolites, and its late Floian to Darriwilian part is composed of fossil-rich, bioturbated, cherty mud-wackestone, skeletal grainstone and shale, with local siltstone and glauconitic horizons. The succession can be subdivided into five third-order depositional sequences, which are interpreted as representing the Sauk IIIB Supersequence known from elsewhere on the Laurentian platform
Beck's birds of northeast New Guinea.
No full text36 pages : illustrations, maps ; 26 cm.In 1928-1929 Rollo Beck discovered in New Guinea a spectacular new species of bowerbird, Sericulus bakeri, which according to his specimen labels he collected near the previously well-studied lowland town and former colonial capital of Madang. That seemed so implausible that suspicions arose that Beck had intentionally falsified the locality--especially when it eventually turned out that the new bowerbird is instead confined to the nearby Adelbert Mountains. Beck made this discovery in the course of amassing large collections in northeast New Guinea that, in fact, have never been published as a whole, although Ernst Mayr (1941) in his List of New Guinea Birds included some of Beck's records. Much doubt has remained about Beck's collecting localities. Hence we have now reconstructed Beck's itinerary on the basis of his field diary and specimen register; the letter by his wife who accompanied him; a spreadsheet of his cataloged specimens in the American Museum of Natural History (AMNH); and correspondence, records, and photographs archived at the AMNH. We show that Beck collected at 10 sites grouped into three areas: the foothills of the Adelbert Mountains and adjacent lowlands, the westernmost foothills of the Huon Peninsula, and the Cromwell Mountains in the east of the Huon Peninsula. We assemble a table listing all species that Beck collected at each of the 10 sites. For each site, we discuss the upland species, open-country species, and other groups of species collected there. Those results illuminate the upland avifaunas of the Adelbert Mountains and the Huon Peninsula, range borders in Northeast New Guinea, and a possible Massenerhebung effect in the Cromwell Mountains. It is clear that Beck's labeling of his Sericulus bakeri specimens as collected at Madang was not done with intent to mislead, but is instead readily understandable from Beck's previous collecting experiences and his preparation for his New Guinea trip
Micro-CT visualization of the rostrum of the weevil, Phynchites auratus. Supplemental Material for 'The weevil rostrum (Coleoptera, Curculionoidea) : internal structure and evolutionary trends. (Bulletin of the American Museum of Natural History, no. 416)'
No full textMicro-CT visualization of the rostrum of the weevil, Phynchites auratus. Supplemental Material for 'The weevil rostrum (Coleoptera, Curculionoidea) : internal structure and evolutionary trends. (Bulletin of the American Museum of Natural History, no. 416)
New material of Eocene Helaletidae (Perissodactyla, Tapiroidea) from the Irdin Manha Formation of the Erlian Basin, Inner Mongolia, China, and comments on related localities of the Huheboerhe area. (American Museum novitates, no. 3878)
No full text44 pages : illustrations (some color), maps ; 26 cm.Perissodactyls first appeared at the beginning of the early Eocene and reached their highest diversity, dominating contemporaneous mammalian faunas in species richness during the middle Eocene. Tapiroidea is an important perissodactyl group that includes earliest-Eocene forms, such as Orientolophus as well as extant taxa (such as Tapirus), that preserves numerous plesiomorphic characters. Because tapiroids were widely distributed in North America and Asia in the middle Eocene, they have played an important role in biostratigraphically defining middle Eocene North American Land Mammal Ages (NALMA) and Asian Land Mammal Ages (ALMA), respectively, as well as in biostratigraphic correlation between the two continents. Here we report a new cranial specimen of middle Eocene helaletid Paracolodon fissus and a maxilla of Desmatotherium mongoliense from the middle Eocene Irdin Manha Formation of the Erlian Basin, Inner Mongolia, China. Paracolodon fissus was previously assigned to Desmatotherium, Helaletes, or Colodon, whereas D. mongoliense was assigned to Helaletes or Irdinolophus by different authors. Based on the new material described in this report, we are able to clarify the affinities and phylogenetic position of these species according to morphological comparison and phylogenetic analyses. We maintain the genus Paracolodon for P. inceptus and P. fissus from Asia and reassign mongoliense to Desmatotherium. Fossils of perissodactyls and other groups from the Irdin Manha Formation favor correlation of the Irdinmanhan ALMA with the early and middle Uintan NALMA (Ui1-Ui2). Through our field investigation, we also clarified that the localities "7 miles southwest" and "10 miles southwest" of Camp Margetts, originally used by the American Museum of Natural History's Central Asiatic Expedition (CAE), correspond to the localities currently known as Huheboerhe and Changanboerhe, respectively
Two new genera of tritylodonts.
No full text35 pages : illustrations (some color), map ; 26 cm.Two new genera and species of Tritylodontidae, Shartegodon altai and Nuurtherium baruunensis, are described and compared with other known tritylodontids. The new taxa are represented by two partial skulls and, in the case of Nuurtherium, postcranial elements. They were collected from the lower part of the Ulan Malgait Sequence (Upper Jurassic) in the Shar Teg locality, Gobi-Altai Aimag, southwestern Mongolia. The upper postcanine teeth of these two genera have unique cusp formulae that differentiate them from other tritylodontids. As has been suggested for most tritylodontids in general, these two new genera may have been herbivorous
Arabian Tarsalia.
No full text28 pages : color illustrations ; 26 cm.The uncommonly encountered bee tribe Tarsaliini (Apinae) is recorded from the Arabian Peninsula for the first time, and based on a new species of the genus Tarsalia Morawitz. The tribes Ancylaini and Tarsaliini are diagnosed and their differences highlighted. Tarsalia kindahensis Engel, new species, is described and figured from the eastern portion of the Najd of central-eastern Saudi Arabia (Qassim and Riyadh regions). The new species is most similar to T. mimetes (Cockerell), known only from Egypt and Sudan, as well as the larger T. persica (Warncke) from Iran. These three species are morphologically and largely geographically distinct from the remainder of the genus, and are segregated into a new subgenus, Astibomelissa Engel. An updated and corrected checklist of the genera and subgenera of bees recorded from Saudi Arabia is appended
Supplemental Material for 'Molecular phylogenetics of the wrens and allies (Passeriformes, Certhioidea), with comments on the relationships of Ferminia. (American Museum novitates, no. 3887)'
No full textSupplemental Material for 'Molecular phylogenetics of the wrens and allies (Passeriformes, Certhioidea), with comments on the relationships of Ferminia. (American Museum novitates, no. 3887)