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Excavations at Gaván-complex sites.
No full text2 volumes (896 pages) : illustrations, maps ; 26 cm.Between 1983 and 1992, the authors conducted an archaeological project that involved five years of survey and excavation in a 450 km² study region that included portions of the high llanos (savanna grasslands) and adjacent Andean piedmont in the state of Barinas, Venezuela. Fieldwork (in 1983-1988) was followed by four years of laboratory analysis in the Departamento de Antropología at the Instituto Venezolano de Investigaciones Científicas (IVIC) in Altos de Pipe, state of Miranda. Our project was designed to investigate whether during pre-Hispanic times the study region had witnessed the development of a chiefdom, which we defined as a regional (multivillage) polity led by a paramount chief who ruled from a regional center and presided over a chiefly administration that was centralized but not internally specialized.... Our fieldwork comprised three seasons of regional survey, during the summer months of 1983-1985, followed by two dry seasons (January-May) of excavation in 1986 and 1988. On survey we recorded a total of 103 archaeological sites in our study region that was centered on the Canaguá River valley, extending across the high llanos (savanna grasslands) and adjacent Andean piedmont. Site occupations pertained to two chronological periods: an early period dating to A.D. 300-1000 and a later period dating to A.D. 1000-1850, taking our coverage into the early historic period. We called the earlier of these occupations on the high llanos the Gaván complex, divided into the Early Gaván phase (A.D. 300-550) and the Late Gavaán phase (A.D. 550-1000), the latter of which exhibited many of the characteristics consistent with the expected archaeological manifestations of a chiefly society. There was convincing evidence of a regional hierarchy...
Phylogenetic studies of apoid wasps (Hymenoptera, Apoidea) with insights into the evolution of complex behaviors.
No full textxiv, 256 pages : illustrations (chiefly color)The wasp superfamily Apoidea -- a group composed of more than 20,000 species of solitary, cleptoparasitic, and social bees, as well as a paraphyletic grade of more than 9,600 species of predatory and cleptoparasitic wasps -- has played an outsized role in the history of behavioral research. Favorite subjects of field naturalists and ethologists for more than two hundred years, these insects have evolved a tremendous diversity of behavioral strategies, each one an equally successful variation on a shared ancestral groundplan. Understanding the course of these evolutionary derivations and innovations is an important part of understanding insect behavior in toto, and one that requires a phylogenetically informed, comparative approach. As a contribution to ongoing efforts in apoid phylogenetic systematics -- and by extension to the study of behavioral evolution within the group -- the current work presents four phylogenetic studies of apoid taxa, with an additional fifth study examining the placement of Apoidea within Hymenoptera as a whole. Each provides some insight into the evolution of a complex behavioral syndrome, namely the development of predatory behavior from within a parasitoid wasp clade (Chapter II), the origins of cleptoparasitism in apid bees (Chapter III), trends in prey choice among philanthine wasps (Chapters IV and V), and innovations in nesting behavior within thread-waisted wasps (Chapter VI). In the first of these studies, I use a combination of direct optimization phylogeny reconstruction and clade sensitivity analysis to re-examine a previously published total evidence dataset based on 111 taxa from across Hymenoptera. This new analysis simultaneously reveals and formalizes deep topological instabilities within this important insect order, and shows how such instability can complicate back-of-the-envelope reconstructions of behavioral evolution (e.g., the origins of aculeate predatory behavior from within a paraphyletic "Parasitica"). In the second, I demonstrate once again the importance of combining multiple classes of phylogenetically informative characters through a simultaneous reanalysis of the bee family Apidae. By merging previously published datasets based on molecular, behavioral, and adult and larval morphological characters (and by providing new adult and larval character codings for taxa previously represented by molecular data alone), I add qualified support to a recently published, nucleotide-derived hypothesis concerning the origins of cleptoparasitism. This hypothesis -- that the trait evolved fewer times than previously supposed, with the nomadine and "melectine" lineages sharing a common cleptoparasitic ancestor -- is corroborated under a variety of different transformation cost parameters and appears relatively robust to the addition of morphological and behavioral data. The next two studies present the results of the most taxonomically comprehensive phylogenetic analyses of the digger wasp subfamily Philanthinae (Apoidea: Crabronidae) to date. While Chapter IV represents the first molecular analysis of the group to include species level terminals from all eight genera and all four tribes, Chapter V expands that work to include 66 newly coded morphological and behavioral characters. Although basal relationships among the four tribes remain either ambiguous or poorly supported, monophyly of the hyperdiverse, cosmopolitan genus Cerceris is strongly suggested for the first time -- a finding that challenges previous notions concerning the evolution of prey choice within the "beetlewolf" tribe Cercerini. Finally, the last study briefly examines relationships among the so-called "thread-waisted wasps" of the family Sphecidae sensu stricto as a prelude to a larger study of nest evolution within the group. While maximum parsimony analysis of 16 nest-related behavioral characters produces a largely unresolved topology, cladistic analysis of a three-gene dataset reveals new cases of paraphyly at both the tribal and generic levels. I briefly discuss the implications of this latter topology for our understanding of nest evolution within the group.Richard Gilder Graduate School at the American Museum of Natural History
High resolution images for 'A systematic review of Sulawesi Bunomys (Muridae, Murinae) with the description of two new species. (Bulletin of the American Museum of Natural History, no. 392)'
No full textHigh resolution images for 'A systematic review of Sulawesi Bunomys (Muridae, Murinae) with the description of two new species. (Bulletin of the American Museum of Natural History, no. 392)' - http://hdl.handle.net/2246/657
Goler Formation eutherian mammals.
No full text57 pages : illustrations (some color), maps ; 26 cmThe Goler Formation is the only rock unit on the West Coast of North America that has yielded a diverse assemblage of Paleocene vertebrates. Intense prospecting of strata representing member 4 of the formation over the past two decades has resulted in recovery of over 70 specimens of eutherian mammals, representing 18 species. All specimens were recovered from member 4a and the lower part of member 4b, except an isolated tooth referred to Phenacodus cf. P. vortmani from member 4d in the uppermost part of the formation. Three taxa are new, the plesiadapid, Nannodectes lynasi, and two hyopsodontid condylarths, Promioclaenus walshi and Protoselene ashtoni. Also present are four species of Phenacodus, two species of Protictis, and single species representing Goleroconus, Mimotricentes, Lambertocyon, Ignacius, Paromomys, Bessoecetor, Thryptacodon, Dissacus, and a taeniodont. The mammalian fauna from member 4a and the lower part of member 4b is collectively referred to as the Goler Assemblage because taxa recovered from sites throughout this 500 m stratigraphic interval are too similar to subdivide into discrete biostratigraphic units. Based on comparison to faunas from well-known Tiffanian sites in the Western Interior, the Goler Assemblage is probably middle Tiffanian (Ti3-Ti4a), although a Ti5a age is also possible. The Goler Assemblage exhibits significant endemism as 40% of its taxa are not reported elsewhere and only four of 18 Goler Assemblage eutherians can be confidently referred to known species. Comparison to seven Ti3-Ti4a aged sites from the Western Interior indicates that the Goler Assemblage has a closer affinity to more southern faunas (southern Wyoming, Colorado, and Texas), than northern faunas (northern Wyoming, North Dakota, and western Canada), and is most similar to the mammalian assemblage from the Ledge Locality in the Bison Basin of southern Wyoming. Presence of late Paleocene-early Eocene marine strata in the uppermost member of the Goler Formation indicates that the Goler Basin was probably adjacent to the Pacific Ocean during most of its existence. Also, significant distances and one or more paleodrainage divides separated the Goler Basin from Western Interior basins, factors that limited the dispersal of mammals between the West Coast and the continental interior and contributed to the formation of a discrete faunal province on the West Coast of North America during the late Paleocene
Psaenythisca, a new genus of bees from South America (Apoidea, Andrenidae, Protandrenini) with a description of the nesting biology and immature stages of one species. (American Museum novitates, no. 3800)
Get PDF32 pages : illustrations, maps ; 26 cm.A new bee genus from Argentina, Psaenythisca, is described and includes three species: P. flavifrons (Vachal, 1909), n. comb. (originally described as Psaenythia), P. wagneri (Vachal, 1909), n. comb. (originally described as Psaenythia), and P. punctata (Urban, 2009), n. comb. (originally described as Anthrenoides). The new genus is proposed based on a comparative study of the Protandrenini lineages. Psaenythisca is closely related to Cephalurgus and Rhophitulus, and can be distinguished mainly by the forewing with three submarginal cells, premarginal area of S2 to S5 of male with dense pubescence, distal margin of S6 of male slightly emarginated, and male genitalia with relatively broad basal sclerite. Among Protandrenini genera with three submarginal cells, it differs from Anthrenoides and Psaenythia by the combination of male genitalia with a basal sclerite, metasomal terga lacking yellow markings, propodeum rounded, middle tibial spur of the female finely serrate, and slender basal area of S8 of male. In addition, a lectotype is designated for Psaenythia (Psaenythia) wagneri Vachal, 1909. The holotype of P. flavifrons and the lectotype of P. wagneri are redescribed, and the female of P. flavifrons and male of P. punctata are described for the first time. An identification key to, and distribution maps of, the species of Psaenythisca are also provided. Nearly a quarter of a century ago, Arturo Roig-Alsina and the second author discovered a communal nest of one of the species, now known as Psaenythisca wagneri (Vachal, 1909). The nest descended approximately 2 m into the ground and is described herein. From this nest, provision masses, eggs, larvae, and pupae were retrieved as well as developmental and behavioral information. The immatures are described and compared with those of related taxa, and the developmental and behavioral information are recorded. Of special interest is the fact that males exhibit a wide range of head sizes and head shapes. All of this gives rise to intriguing new questions for future investigation
New records of Hyachelia tortugae and H. lowryi.
No full text12 pages : illustrations (some color), map ; 26 cm. Specimens collected by the American Museum of Natural History's Center for Biodiversity and Conservation as part of its ongoing program of Pacific sea turtle research and conservation. (Page 3)Amphipods of the genus Hyachelia collected during an epibiont survey conducted over three years (2009, 2010, and 2011) at Palmyra Atoll are reported. Both known species, i.e., Hyachelia tortugae Barnard, 1967, and Hyachelia lowryi Serejo and Sittrop, 2009, were collected from Pacific green turtles, Chelonia mydas (Linnaeus). Given the increased awareness of epibionts and the desire of researchers to make positive identifications, figures of the diagnostic features of both amphipod species are presented. The significance of the cooccurrence of these two species on Pacific green turtles (Chelonia mydas) is discussed
Echiothrix leucura and E. centrosa.
No full text87 pages : illustrations (some color), map ; 26 cm.Among the 15 known genera of murine rodents endemic to the island of Sulawesi, is the shrew rat genus Echiothrix. Physically large (length of head and body = 182-235 mm; weight = 215-310 g) with a bicolored tail typically longer than head and body (100%-135% of head and body length), elongate hind feet (48-55 mm), large ears (31-35 mm), long and thin muzzle, spinous fur, and tiny molars relative to size of skull (length of molar row = 12%-13% of occipitonasal length), Echiothrix was named and described in 1867 and through the years has been treated as monotypic or containing up to three species. Results from analyses of morphometric traits derived primarily from cranial and dental measurements document the presence of two species. Echiothrix leucura (Gray, 1867) is restricted to the northern peninsular mainland east of the Gorontalo region (00°31ʹ N, 123° 03ʹ E). This distribution is concordant with that of four other murids endemic to the northeastern tip of the northern peninsula: Bunomys fratrorum, Taeromys taerae, Rattus xanthurus, and R. marmosurus. Echiothrix centrosa Miller and Hollister, 1921 (Echiothix brevicula Miller and Hollister, 1921, is a synonym), is documented by specimens from the northern peninsula west of the Gorontalo region and in the central portion of the island; 19 other murine species are also known only from the core of Sulawesi. Whether the range of E. centrosa extends to the eastern, southeastern, and southwestern peninsulas is at present unknown. Echiothrix leucura has a more elongate skull compared with E. centrosa (greater lengths of skull, rostrum, diastema, and bony palate), a wider interorbital region, larger braincase, narrower bony palate and mesopterygoid fossa, shorter incisive foramina, and appreciably larger molars; the two species also differ in frequencies of particular molar cusps and cusplets. Both species of Echiothrix are nocturnal, terrestrial, and occupy habitats in tropical lowland evergreen rain forest. Natural history observations made in the field for Echiothrix centrosa show it to be primarily vermivorous; other natural history observations derived from field work in central Sulawesi are provided. One aspect of that natural history is the ectoparasitic load borne by E. centrosa. This shrew rat is host to at least four species of ticks (Haemaphysalis kadarsani, Haemaphysalis hystricis, Haemaphysalis sp. and Amblyomma sp.), a tiny fur mite (Listrophoroides echiothrix), mesostigmatid mites belonging to the genus Laelaps, currently undetermined chiggers, a flea (Farhangia quattuordecimdentata), and a new species of sucking louse described herein as Polyplax beaucournui. This louse has tibiotarsal claws adapted for grasping slender soft hairs in the pelage and not the wide host spines; female lice also attach their eggs only to these slender hairs. The closest relative of Echiothrix is probably Paucidentomys vermidax, another Sulawesian endemic shrew rat that is also vermivorous but lacks molars and has been collected only in montane forests. The present report documents morphological and distributional limits of species in Echiothrix, places one of those species in an ecological and parasitological landscape, and generally contributes to knowledge covering endemic murid species diversity and identifying unique zoogeographical areas on Sulawesi
High resolution images for Taxonomic review of the goblin spiders of the genus Dysderoides Fage and their Himalayan relatives of the genera Trilacuna Tong and Li and Himalayana, new genus (Araneae, Oonopidae). (Bulletin of the American Museum of Natural History, no. 387)
No full textHigh resolution images for Taxonomic review of the goblin spiders of the genus Dysderoides Fage and their Himalayan relatives of the genera Trilacuna Tong and Li and Himalayana, new genus (Araneae, Oonopidae). (Bulletin of the American Museum of Natural History, no. 387); Bulletin no. 387 can be accessed at this link: http://hdl.handle.net/2246/652