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New specimens of Anchiornis huxleyi (Theropoda, Paraves) from the late Jurassic of northeastern China. (Bulletin of the American Museum of Natural History, no. 411)
No full text66 pages : illustrations (chiefly color) ; 26 cm.Four new specimens of Anchiornis huxleyi (PKUP V1068, BMNHC PH804, BMNHC PH822, and BMNHC PH823) were recently recovered from the late Jurassic fossil beds of the Tiaojishan Formation in northeastern China. These new specimens are almost completely preserved with cranial and postcranial skeletons. Morphological features of Anchiornis huxleyi have implications for paravian character evolution and provide insights into the relationships of major paravian lineages. Anchiornis huxleyi shares derived features with avialans, such as a straight nasal process of the premaxilla and the absence of an external mandibular fenestra in lateral view. However, Anchiornis huxleyi lacks several derived deinonychosaurian features, including a laterally exposed splenial and a specialized raptorial pedal digit II. Morphological comparisons strongly suggest Anchiornis is more closely related to avialans than to deinonychosaurians or troodontids. Anchiornis huxleyi exhibits many conservative paravian features, and closely resembles Archaeopteryx and other Jurassic paravians from Jianchang County, such as Xiaotingia and Eosinopteryx. The other Jianchang paravian, Aurornis xui, is likely a junior synonym of Anchiornis huxleyi
On the goblin spider genus Birabenella.
Get PDF17 pages : illustrations (some color), color map ; 26 cm.The taxonomy of the poorly known South American goblin spider genus Birabenella Grismado (Araneae: Oonopidae) is updated in light of recently collected material. Three new species are described: B. kamanchaca, from northern Chile, B. portai, from northwestern Argentina, and B. chincha, from southern Peru, where the genus is reported for the first time. The diagnosis of the genus is updated; the presence of the ventral digitiform projection on the male copulatory bulb in the three newly described species supports this character as a putative synapomorphy for the genus. Additionally, all species in this genus possess unipectinate tarsal claws. Preliminary observations indicate that there is some degree of variability in tarsal organ morphology
Supplemental Material for 'A new Tropidurus (Tropiduridae) from the semiarid Brazilian Caatinga : evidence for conflicting signal between mitochondrial and nuclear loci affecting the phylogenetic reconstruction of South American collared lizards. (American Museum novitates, no. 3852)'
No full textSupplemental Material for 'A new Tropidurus (Tropiduridae) from the semiarid Brazilian Caatinga : evidence for conflicting signal between mitochondrial and nuclear loci affecting the phylogenetic reconstruction of South American collared lizards. (American Museum novitates, no. 3852)' - http://hdl.handle.net/2246/663
High resolution images for 'Nineteen new genera and 82 new species of Cremnorrhinina from Australia, including analyses of host relationships and distributions (Insecta, Hemiptera, Miridae, Phylinae, Cremnorrhinini). (Bulletin of the American Museum of Natural History, no. 401)'
No full textHigh resolution images for 'Nineteen new genera and 82 new species of Cremnorrhinina from Australia, including analyses of host relationships and distributions (Insecta, Hemiptera, Miridae, Phylinae, Cremnorrhinini). (Bulletin of the American Museum of Natural History, no. 401)' - http://hdl.handle.net/2246/664
Comparative study of mature euglossine larvae.
No full text16 pages : illustrations (some color)
"June 14, 2016."Herein are described and illustrated the mature larvae of the following species assigned to the Euglossini: Eufriesea surinamensis (Linnaeus), Eufriesea mussitans (Fabricius), Euglossa (Euglossa) cordata (Linnaeus), Eulaema (Apeulaema) polychroma (Mocsáry). They are compared both with one another and with previous accounts of other taxa assigned to the tribe, and a taxonomic key is presented. The paper concludes with a preliminary larval characterization of the tribe
Ornithischian dinosaur Haya griva.
No full text19 pages : illustrations (some color), 1 color map ; 26 cm.Although Mesozoic fossils are quite common in the Gobi Desert of Central Asia, it is often difficult to correlate among different localities because of a dearth of rocks amenable to absolute dating. Specifically, correlating between the eastern Gobi Desert and more western localities has been challenging. Here we give a Santonian-Campanian age for the enigmatic Zos Canyon beds in the Nemegt basin. This is based on the occurrence of the primitive ornithopod dinosaur Haya griva at both eastern Gobi exposures of the Javkhlant Formation and the Zos Canyon locality
A new Tropidurus (Tropiduridae) from the semiarid Brazilian Caatinga : evidence for conflicting signal between mitochondrial and nuclear loci affecting the phylogenetic reconstruction of South American collared lizards. (American Museum novitates, no. 3852)
Get PDF66 pages : illustrations (some color), color maps ; 26 cm.Tropidurus Wied, 1825, is one of the most ubiquitous lizard genera distributed in open habitats of tropical and subtropical South America. Nevertheless, the broad representation of specimens of this group in scientific collections is hardly reflected in our knowledge of its taxonomic diversity. Most species currently assigned to Tropidurus began to be uncovered in the early 1980's and additional populations in need of formal taxonomic treatment have been cataloged ever since. Herein, we name Tropidurus sertanejo, n. sp., a new species of the T. torquatus group endemic to the semiarid Brazilian Caatinga. Tropidurus sertanejo, n. sp., is currently known from two isolated populations in the municipalities of Caetité and Ibotirama, State of Bahia, Brazil. This is the only species of the T. torquatus group lacking granular mite pockets on the lateral neck, and it is also diagnosable by having a conspicuous bronze-colored head, a light-brown dorsal body with small pale salmon spots, and small body size in comparison with most congeners. Phylogenetic analyses recovered a paraphyletic Tropidurus, but firmly supported T. sertanejo, n. sp., as member of a monophyletic T. torquatus species group. Trees generated by independent analyses of nuclear and mitochondrial sequence data conflicted with our total evidence phylogenetic hypotheses. Since topological disagreements were detected among phylogenetic trees resulting from maximum parsimony (MP) and maximum likelihood (ML) reconstructions, and MP analyses do not require distinct evolutionary models or partition schemes to be defined prior to conduction of phylogenetic reconstruction, these factors were considered unlikely to explain all the variation in the observed results, favoring the interpretation of conflicting phylogenetic signal. Because detailed information on the distribution, population size, and ecological requirements of T. sertanejo, n. sp., are currently unavailable, we recommend the species to be listed as "data deficient" following the rules proposed by IUCN
Archaeological investigations along the Ruby Pipeline.
No full text405 pages : illustrations (some color), maps ; 26 cm.The Ruby Pipeline originates in Opal, Wyoming, travels westward across Utah and Nevada, and terminates in Malin, Oregon. Almost 360 miles of the line is in Nevada, where it crosses through some of the most remote, sparsely populated land in the lower 48 states. Despite the remote nature of this corridor, it has produced a rich archaeological record reflecting a dynamic history of land-use pattern changes over a period of at least 13,000 years. Archaeological excavations were conducted at 578 prehistoric sites prior to construction of the pipeline. The sites were distributed across four ecological regions, including (from west to east): the High Rock Country, Upper Lahontan Basin, Upper Humboldt Plains, and Thousand Springs Valley. First evidence of human occupation dates to the Paleoindian (14,500-12,800 cal b.p.) and Paleoarchaic (12,800-7800 cal b.p.) periods, when people spent most of their time in the High Rock Country where important economic resources reached their highest densities. Paleoindian findings are limited to a series of Great Basin Concave Base projectile points and small obsidian flaked stone concentrations. Paleoarchaic sites are much more common, and tend to be represented by Great Basin Stemmed projectile points, bifaces, and a limited number of other flaked stone tools. Most of these assemblages reflect small groups of hunters refurbishing their tool kits as they traveled through the area. An important exception to this pattern was found at Five Mile Flat along the west end of pluvial Lake Parman where two significant habitation sites dating to 11,180 cal b.p. were discovered. One of these sites includes a house floor, which is the oldest ever found in the Great Basin. Despite the warm-dry conditions that characterized much of the middle Holocene, it appears that human populations nearly doubled during the Post-Mazama Period (7800-5700 cal b.p.). Most activity remained concentrated in the High Rock Country, but evidence for occupation begins to trickle out into the Upper Lahontan Basin and Upper Humboldt Plains regions as well. Most of the artifact assemblages remain rather narrow, often composed of Northern Side-notched and Humboldt Concave Base points, bifaces, and debitage, and reflect use of the region by mobile groups of hunters. Major changes took place with the arrival of the Early Archaic (5700-3800 cal b.p.) and continued forward into the Middle Archaic Period (3800-1300 cal b.p.). Early Archaic projectile points are largely represented by Humboldt and Gatecliff forms. It appears that population densities increased almost fourfold from the preceding interval, and all four regions experienced significant occupation for the first time. Simultaneous to this population increase and dispersal, a full complement of site types began to emerge, with large-scale residential areas becoming significant for the first time. This trend continued forward into the Middle Archaic Period where the relative frequency of residential sites almost doubled compared with the Early Archaic interval. Plant macrofossil and archaeofaunal assemblages also become more abundant and diversified at this time, probably marking a broadening of the diet breadth. This general trajectory extends into the Late Archaic (1300-600 cal b.p.) and Terminal Prehistoric periods, as people continued to expand into a wider range of habitats. This was particularly case for the latter interval, as the habitat preferences that made sense for over 12,000 years were upended, with population densities highest in the Upper Humboldt Plains and Thousand Springs Valley. This reorientation corresponds to the arrival of Numic speaking populations, especially the Western Shoshone who appear to have reached northern Nevada much earlier than the Northern Paiute, and is probably linked to a greater emphasis on small-seeded plants that are abundantly present in their territory. Although low ranked compared to many other foods, with the proper technology and work organization, small seeds could support higher population densities than was the case earlier in time. Finally, the discovery of obsidian in multiple Terminal Prehistoric sites from sources located much further away than any other time in the past may signal the earliest use of horses in northern Nevada
Miocene litoptern skull.
No full text76 pages : illustrations (some color), maps ; 26 cm.The Huayquerías Formation (late Miocene, Huayquerian SALMA) is broadly exposed in west-central Argentina (Mendoza). The target of several major paleontological expeditions in the first half of the 20th century, the Mendozan Huayquerías ("badlands") have recently yielded a significant number of new fossil finds. In this contribution we describe a complete skull (IANIGLA-PV 29) and place it systematically as Huayqueriana cf. H. cristata (Rovereto, 1914) (Litopterna, Macraucheniidae). The specimen shares some nonexclusive features with H. cristata (similar size, rostral border of the orbit almost level with distal border of M3, convergence of maxillary bones at the level of the P3/P4 embrasure, flat snout, very protruding orbits, round outline of premaxillary area in palatal view, and small diastemata between I3/C and C/P1). Other differences (e.g., lack of sagittal crest) may or may not represent intraspecific variation. In addition to other features described here, endocast reconstruction utilizing computer tomography (CT) revealed the presence of a derived position of the orbitotemporal canal running below the rhinal fissure along the lateroventral aspect of the piriform lobe. CT scanning also established that the maxillary nerve (CN V₂) leaves the skull through the sphenoorbital fissure, as in all other litopterns, a point previously contested for macraucheniids. The angle between the lateral semicircular canal and the plane of the base of the skull is about 26°, indicating that in life the head was oriented much as in modern horses. Depending on the variables used, estimates of the body mass of IANIGLA-PV 29 produced somewhat conflicting results. Our preferred body mass estimate is 250 kg, based on the centroid size of 36 3D cranial landmarks and accompanying low prediction error. The advanced degree of tooth wear in IANIGLA-PV 29 implies that the individual died well into old age. However, a count of cementum lines on the sectioned left M2 is consistent with an age at death of 10 or 11 years, younger than expected given its body mass. This suggests that the animal had a very abrasive diet. Phylogenetic analysis failed to resolve the position of IANIGLA-PV 29 satisfactorily, a result possibly influenced by intraspecific variation. There is no decisive evidence for the proposition that Huayqueriana, or any other litoptern, were foregut fermenters
Camelops osteology.
No full text45 pages : illustrations (chiefly color), map ; 26 cm.During the past century, fossils of Pleistocene camels have been occasionally reported from unglaciated regions of Alaska and Yukon (collectively known as eastern Beringia), yet detailed descriptions of these materials are limited or lacking altogether. The detailed osteological treatment presented here establishes that these fossils are virtually indistinguishable from the species Camelops hesternus, a common member of Blancan to Rancholabrean faunas and known best from temperate regions of western North America. Metrically, high-latitude members of C. hesternus seem to have been smaller bodied than representatives from more southerly parts of the species range, a finding that is consistent with body-mass differences among populations of other large mammals whose ranges extended into the far north. The presence of C. hesternus in Alaska and Yukon was likely episodic, limited to relatively warm intervals such as the Last Interglaciation (Sangamonian)