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New species of Lonchophylla (Chiroptera, Phyllostomidae) from the eastern Andes of northwestern South America. American Museum novitates, no. 3635.
No full text16 p. : ill., maps ; 26 cm.
Includes bibliographical references (p. 14-15).Since 2004 five new species have been described in the nectar-feeding phyllostomid bat genus Lonchophylla. All the new species are endemic to one Neotropical ecoregion, suggesting that more species remain to be discovered among collected specimens currently referred to several widespread taxa. Herein we describe a new species, Lonchophylla orienticollina, endemic to the middle elevations of the eastern Andes of Venezuela, Colombia, and Ecuador. The new species superficially resembles its sympatric congener L. robusta, but its cranial morphology and combination of measurements are distinctive. Throughout its range, L. orienticollina is sympatric with L. robusta, and it also overlaps with L. handleyi in the Cordillera Oriental of Ecuador. The evolutionary processes leading to the divergence among Lonchophylla species, as well as the ecological mechanisms that enable multiple, subtly different species to coexist will remain obscure without new field and phylogenetic studies
Behavior of Coelioxys coturnix.
No full text15 p. : ill. ; 26 cm.
Includes bibliographical references (p. 15).In an attempt to determine whether Coelioxys and Radoszkowskiana, both cleptoparasitic members of the Megachilini, had a common cleptoparasitic ancestor, an investigation of the nesting biology and immature stages of C. (Allocoelioxys) coturnix Pérez was undertaken in Egypt. The purpose was to compare these aspects of this species with the results of a recent study of R. rufiventris (Spinola) and certain other species of Coelioxys (Rozen and Kamel, 2007). The egg of C. coturnix is deposited on the egg of Megachile minutissima Radoszkowski after the host female departs to collect cell-closure material. On hatching, the first instar, still surrounded by egg chorion, bites the developing host egg and consumes the entire egg content before feeding upon the host provisions. This behavior contrasts with certain other species of Coelioxys, whose eggs are hidden in the host cell while it is being provisioned and third instars normally kill the young host larvae. Because the behavior of C. coturnix closely mirrors that of R. rufiventris, the authors conclude that two modes of cleptoparasitism have developed in Coelioxys and that Coelioxys and Radoszkowskiana possibly had a common cleptoparasitic ancestor. The five larval instars of C. coturnix are described and compared with those of other Coelioxys species, and its first instar is compared with that of R. rufiventris
Phylogeny and revision of Paretroplus
No full text151 p. : ill. (1 col.) ; 26 cm.Includes bibliographical references (p. 135-139).A species-level phylogeny for Etroplinae is presented, based on the simultaneous analysis of morphological and nucleotide characters, and species of the endemic Malagasy genus Paretroplus are taxonomically revised, including the description of two new species. Relative to most other cichlid genera, Paretroplus is diagnosed by numerous anatomical features, including morphology of the gas bladder, neurocranium, oral jaws and dentition, and suspensorium. Keys to the genera of Malagasy-South Asian cichlids and to the species of Paretroplus are provided. Paretroplus is endemic to Madagascar and is the sister genus to Etroplus, endemic to southern India and Sri Lanka. Together these two genera comprise the subfamily Etroplinae. Paretroplus comprises 12 species, two of which are described herein as new. Three morphologically distinct clades are recovered within Paretroplus, one comprising the comparatively elongate, primarily riverine and rheophilic species P. damii, P. nourissati, P. tsimoly, and P. lamenabe, new species, the second comprising the deep-bodied, primarily lacustrine species P. polyactis, P. petiti, P. kieneri, P. maculatus, P. menarambo, P. maromandia, and P. dambabe, and the third comprising the shallow-bodied and highly mottled species P. kieneri and P. gymnopreopercularis, new species, which occur in both lentic and lotic habitats. Monophyly of Etroplinae and Etroplus are also discussed and diagnostic anatomical features are presented for both clades. The sister-group relationship between Etroplus and Paretroplus represents a well-corroborated transoceanic link within Cichlidae, a pattern congruent with the Mesozoic fragmentation of Gondwana. The anterior of the gas bladder is highly modified in Etroplinae, reaching its most derived configuration in Paretroplus, in which multiple, structurally complex and rigid anterior bullae expand into large exoccipital recesses, forming a mechanical (5 otophysic) connection between the gas bladder and inner ear. Evolution of the gas bladder, and its function in conferring increased hearing ability, is discussed in terms of the phylogenetic information this structure provides for reconstructing hypotheses of relationships within Cichlidae
A new platynotan lizard (Diapsida, Squamata) from the late Cretaceous Gobi Desert (Ömnogöv), Mongolia ; American Museum novitates, no. 3605
No full text22 p. : ill. ; 26 cm.Includes bibliographical references
Native American landscapes of St. Catherines Island, Georgia. (Anthropological papers of the American Museum of Natural History, no. 88)
Get PDFIssued March 3, 2008.
3 v. (xiii, 1136 p.) : ill., maps ; 26 cm.
Contents: pt. 1. The theoretical framework -- pt. 2. The data -- pt. 3. Synthesis and implications.Four deceptively simple questions have guided our long-term research into the aboriginal lifeways of St. Catherines Island: 1. How and why did the human landscape (settlement patterns and land use) change through time? 2. To what extent were subsistence and settlement patterns shaped by human population increase, intensification, and competition for resources? 3. What factors can account for the emergence of social inequality in Georgia's Sea Islands? 4. Can systematically collected archaeological evidence resolve the conflicting ethno-historic interpretations of the aboriginal Georgia coast (the so-called 'Guale problem')? Over a span of four decades, the American Museum of Natural History has addressed these four fundamental questions using a broad array of field and analytical techniques. We conducted a 20 percent probabilistic transect survey of St. Catherines Island, walking and probing for buried sites across a series of 31 east-west transects, each 100 m wide. During this initial survey we located 122 archaeological sites, which we tested with more than 400 one-meter by one-meter units. Because the transect sampling was heavily biased toward sites with marine shell, we also conducted a systematic shovel testing program. We also augmented these systematic surveys with a direct shoreline reconnaissance (mostly following the late Holocene surfaces), recording roughly 84 additional shoreline sites on St. Catherines Island. By plotting the distribution of these known-age sites across the Holocene beach ridges, we have developed a detailed sequence documenting the progradation and erosion of beach ridge complexes adjacent to tidal estuaries and oceanward shorelines on the island. To evaluate the results of the 1000+ test explorations and excavations on St. Catherines Island, we have processed 251 radiocarbon determinations, including two dozen dates on 'modern' mollusks (known-age specimens collected prior to atomic bomb contamination) to compute a 'reservoir' correction factor specific to the estuaries around St. Catherines Island (of [Delta]R = -134 [+ or -] 26). The results have been compiled into a dataset of 239 radiocarbon determinations for samples from St. Catherines Island. One hundred and ten of these dates (from 31 distinct mortuary and midden sites) could be directly associated with datable ceramic assemblages, which were classified according to Chester DePratter's (1979, 1991) Northern Georgia Coast chronology .By comparing the results of typological classification with the radiocarbon evidence currently available from St. Catherines Island, we propose a slightly modified ceramic chronology for St. Catherines Island. We analyzed the seasonal growth increments in modern hard clams (Mercenaria mercenaria) for a 9-year interval (beginning in 1975). Mercenaria suitable for seasonal analysis were recovered from nearly 85 percent (110 of 130) of the sites identified and sampled in the island wide survey. We analyzed about 2000 individual hard clam shells recovered from these shell middens and, of these, 1771 individual specimens (or fragments) provided usable growth increment estimates, enabling us to address seasonal patterns during the 5000 years of human history. This study is reinforced by an oxygen isotope study of modern and ancient clams from St. Catherines Island. This transect survey produced an extensive and diverse set of vertebrate faunal remains collected systematically from archaeological sites tested across the entire island. Elizabeth Reitz and her colleagues analyzed this vertebrate faunal assemblage, which contains at least 586 individuals represented by 14,970 vertebrate specimens weighing 21,615 g. These materials provide a solid basis for refining hypotheses not only for St. Catherines Island, but for most coastal locations. With the exception of the first and last occupations (the St. Simons and Altamaha periods), the samples suggest a stable pattern of resource use through time, with little variation through time or across space (although the small sample sizes for each time period and circumscribed geographical setting might constrain this interpretation). She also notes the presence of numerous seasonal indicators in the vertebrate zoo archaeological samples recovered from archaeological sites on St. Catherines Island--including unshed deer antlers, juvenile deer dentition, and shark and sea catfish remains. But we also recognized the importance of examining diverse sources of seasonal information in our attempt to flesh out overall patterns of site utilization. We also include analysis of the vertebrate zooarchaeological assemblages from Meeting House Field and Fallen Tree, two additional sites intensively investigated by the American Museum of Natural History and the University of Georgia. The intensive program of mortuary archaeology has recovered the remains of more than 725 individuals from 18 archaeological sites on St. Catherines Island. More than 90 percent of these remains were analyzed by Clark Spencer Larsen and his colleagues, using a variety of microscopic, biomechanical, and stable isotopic techniques. In this monograph, we address the archaeology of St. Catherines Island using the broad- based theoretical approach known as optimal foraging theory, which is grounded in the more general paradigm of human behavioral ecology (that studies human behavior by applying the principles of natural selection within an ecological context). The broad rubric of 'optimal foraging theory' encompasses a broad range of specific models, each of which employs a unique set of simplifying assumptions and constraints, and each can be used to derive testable hypotheses about foraging behavior under certain environmental circumstances. Each model is a formal, mathematical construct and they share the key assumption that during 'economic' pursuits, the forager will operate to maximize the overall rate of energetic return. Specifically, we have employed three basic models to address the archaeology of St. Catherines Island. The diet-breadth (or prey choice) model addresses the issue of which foods should an efficient forager harvest from all those available on St. Catherines Island. Diet-breadth models predict that foragers will optimize the time spent capturing prey, and employ the simplifying assumptions that all resources are randomly distributed (without patches) and that 'capture/handling' and 'search' times represent the sum total of all time spent foraging. We also apply the patch choice model, which, combined with the central limit theorem, predicts that foraging effort will correlate directly with efficiency rank order, meaning that foragers should spend more time working the higher-ranked patches and less time in patches with lower energetic potential. Finally, we likewise employ the central place foraging model to investigate the time/energy spent processing resources at temporary camps before transport to a residential base. We find central place foraging theory to be useful for addressing the role and location of the residential base as a locus for provisioning offspring and mates or potential mates. This monograph also reports the results of optimal foraging experiments conducted over a 2-year period on St. Catherines Island, specifically addressing procurement and return rates for key marine and terrestrial resources that would have been available to aboriginal foragers on St. Catherines Island.Publisher: American Museum of Natural History, New York, NY
Immatures of rophitine bees, with notes on their nesting biology (Hymenoptera, Apoidea, Halictidae) ; American Museum novitates, no. 3609
No full text35 p. : ill. ; 26 cm.Includes bibliographical references.This study is a taxonomic overview of the known mature larvae and pupae of the Rophitinae (Halictidae). We either describe and illustrate the mature or nearly mature larvae of the following taxa or provide references to their earlier descriptions: Dufourea holocyanea (Cockerell), D. australis australis Michener, D. mulleri (Cockerell), D. novaeangliae (Robertson), Sphecodosoma (Sphecodosoma) dicksoni (Timberlake), Protodufourea eickworti Bohart and Griswold, Xeralictus timberlakei Cockerell, Systropha planidens Giraud, Rophites (Rhophitoides) canus Eversmann, R. (Rophites) algirus trispinosus Pérez, Conanthalictus (C.) conanthi (Cockerell), and C. (Phaceliapis) bakeri Crawford. We present a key to known mature rophitine larvae. We also describe pupae of the following taxa for the first time and compare them with the pupa of S. dicksoni: D. holocyanea, D. australis australis, and R. canus. The phylogenetic relations of the treated taxa are discussed in light of larval characters, and we discuss the pupal characteristics of the entire family. We offer notes on the nesting biology of various taxa whose immatures were treated and synthesize this information with previous accounts from the literature
Falsified data associated with specimens of birds, mammals, and insects from the Veragua Archipelago, Panama, collected by J.H. Batty ; American Museum novitates, no. 3620
No full text37 p. : ill., map ; 26 cm.Includes bibliographical references (p. 32-33).The professional collector Joseph H. Batty obtained birds, mammals, and insects in Panama in 1901 and supposedly 1902, at least some of which have long been thought to have been labeled with suspicious locality information. Examination of catalog records for birds and mammals, the labels of hundreds of specimens of birds, and archival material provided no concrete evidence of Batty collecting anywhere in Panama except on Isla de Coiba and in the vicinity of Boquete and Boquerón in mainland Chiriquí Province. His series of birds from Coiba contains some taxa that are recognizable as endemic subspecies from Coiba but also contains many specimens of the same species belonging to mainland subspecies in addition to species not known to occur on the island. Analysis of the types of labels used by Batty on birds proved useful for determining which Coiba specimens are the more likely to have authentic locality information. Batty's series of mammals from Coiba, upon which four new taxa were based, also probably contains mislabeled specimens. The series of birds and mammals labeled by Batty as having come from the smaller, low-lying Pacific islands of Chiriquí and Veraguas (Veragua Archipelago), with dates of 1902, contains specimens of many taxa that either are highland species or do not occur in the only habitats likely to be present on some of the islands, or that have never been found on any island elsewhere in Panama, including the very large Isla de Coiba. The itinerary reconstructed from specimen labels as well as the number of specimens are not consistent with the realities of transportation or human capabilities. It is concluded that the specimens in this series probably came from the general area of Batty's two mainland localities in Chiriquí and that he never went to the smaller islands. Accordingly, the type locality of the porcupine Coendou rothschildi Thomas, 1902, should be altered from Isla Sevilla to the vicinity of Boquerón, Chiriquí. With very few exceptions, all of Batty's specimens with questionable locality were sold by him to the private collector Walter Rothschild and do not involve specimens that Batty provided to other museums. Another small series of birds, including some very rare ones, obtained through Batty and labeled as from Chitra, Veraguas, also have untrustworthy date and locality information
Species taxonomy, phylogeny and biogeography of the Brontotheriidae (Mammalia, Perissodactyla) ; Bulletin of the American Museum of Natural History, no. 311
Get PDF475 p. : ill., maps ; 26 cm.Includes bibliographical references (p. 420-429).Print copy to be received imminently--Cataloger's note, 6/5/08.The Brontotheriidae is an extinct family of Eocene perissodactyls known from North America, Asia, and, rarely, Eastern Europe. Brontotheres are widely recognized as having evolved very large body size and conspicuous frontonasal horns, although these traits do not characterize every species. Characters shared by all brontotheriids include an anteroposteriorly abbreviated face and an elongate postorbital cranium. Dentally, brontotheriids share bunoselenodont upper molars with a W-shaped ectoloph, isolated lingual cusps, and with paraconules, metaconules, and transverse molar crests that are either vestigial or absent. Early North American paleontologists such as Leidy, Cope, Marsh, and Osborn placed considerable emphasis on brontothere research, however, since Osborn's massive 1929 monograph on North American brontotheres, serious research on this diverse Eocene family has waned. Nonetheless, a great need for a revision of the Brontotheriidae has long been recognized because earlier works on brontothere taxonomy and systematics, particularly those of Osborn, are universally considered problematic due to their reliance on the discredited theory of orthogenesis. The present study reevaluates the species taxonomy of brontotheres based on craniodental materials. All known taxa were considered for revision except North American representatives of Eotitanops, Palaeosyops, and Megacerops. A phylogenetic species concept, where species are defined as the smallest diagnosable clusters of specimens, was adopted for this study. Monospecific quarry samples (mass death assemblages) consistently suggest that certain characters, including canine size, horn size, and many premolar characters show intraspecific polymorphic tendencies; such characters were not generally used to delimit species. All characters found to be monomorphic within mass death assemblages were considered when delimiting taxa. A total of 116 potential species were considered for revision. Among these species, 41 were found to be valid, 34 species were found to be invalid junior synonyms of valid species, 31 species were found to be nonima dubia, and three others were found to be problematic due to extremely fragmentary fossils, but not necessarily invalid. One new species, Wickia brevirhinus, is named and six other potential species are recognized but remain unnamed due to very poor fossil material. Phylogenetic analysis of 47 brontotheriid taxa was undertaken with 227 states distributed among 87 characters. The outgroup method was employed using Hyracotherium, Pachynolophus, Danjiangia, and Lambdotherium. Two analyses were performed, one with ordered multistate characters and another with unordered multistate characters. Both analyses yielded large numbers of most parsimonious trees. A strict reduced consensus was used to identify and prune fragmentary wildcard taxa a posteriori. Not surprisingly, the results of the phylogenetic analysis differ substantially from prior orthogenetic hypotheses of brontothere phylogeny and a radical revision in the higher classification of brontotheres is presented. Eotitanops and Palaeosyops are the most basal members of the Brontotheriidae. All other brontotheres form a clade, Brontotheriinae, which is supported by numerous molar apomorphies suggesting increased functional emphasis on shearing on the outer wall of enamel of the upper molars. Many of the previously named brontothere subfamilies are clearly paraphyletic while others correspond to subclades of the Brontotheriinae and have been assigned new ranks, resulting in a revised classification consisting of internested monophyletic taxa. Nine to twelve intercontinental dispersals, mostly in the middle Eocene (Uintan and Irdinmanhan land mammal "ages") between North America and Asia are implied by the cladistic results. The timing of these dispersals agrees with prior conclusions regarding the timing of large influxes of mammal taxa into North America from Asia. However, the frequency of interchanges is far greater than previously surmised. Following basic MacArthur-Wilson island biogeography theory, North America, the smaller continent, is viewed as a cul-de-sac, receiving repeated waves of immigrants from Asia, the larger continent. However, the phylogenetic results of the Brontotheriidae suggest the possibility that the predominant direction of dispersal could have been in the opposite direction; this result questions the validity of applying island biogeography theory to continent-scale dispersal dynamics
The braincases of two glyptosaurines (Anguidae, Squamata) and anguid phylogeny ; American Museum novitates, no. 3613
No full text24 p. : ill. ; 26 cm.Includes bibliographical references (p. 20-23).Glyptosaurines are an extinct clade of anguids whose remains are common in many Holarctic Paleogene and Cretaceous deposits. Despite their extensive fossil record (comprised mainly of scutes) the braincase is poorly known. Here, we describe braincase morphology in two North American Eocene glyptosaurines, Melanosaurus maximus and Helodermoides tuberculatus. Although generally conservative in their braincase morphology compared with other anguids, these taxa and some other "higher" glyptosaurines possess a dorsally displaced parasphenoid rostrum. The anterior openings for the Vidian canals open almost directly ventral to the parasphenoid rostrum, and the internal carotids exit anteriorly almost directly dorsal to it. Our phylogenetic analysis recovers a monophyletic Glyptosaurinae nested within Anguidae as the sister taxon to a clade containing Gerrhonotinae and Anguinae. According to our analysis, "melanosaurins" are paraphyletic, Placosaurus is paraphyletic, and Anniella is the sister taxon to Anguis
Estimating body mass in New World "monkeys" (Platyrrhini, Primates), with a consideration of the Miocene platyrrhine, Chilecebus carrascoensis ; American Museum novitates, no. 3617
No full text29 p. : ill. ; 26 cm.Includes bibliographical references (p. 17-19).Well-constrained estimates of adult body mass for fossil platyrrhine species (New World "monkeys") are essential for resolving numerous paleobiological questions. However, no consensus exists as to which craniodental measures best correlate with body mass among extant taxa in this clade. In this analysis, we analyze 80 craniodental variables and generate predictive equations applicable to fossil taxa, including the early platyrrhine Chilecebus carrascoensis. We find mandibular length to be the best craniodental predictor of body mass. There is no significant difference in predictive value between osteological and dental measures. Variables associated with the mandible and lower dentition do significantly outperform the cranium and upper dentition. Additionally, we demonstrate that modern platyrrhines differ, morphometrically, from early fossil forms. Chilecebus possesses unusual cranial proportions in several key features, as well as proportionally narrow upper incisors and wide upper cheek teeth. These variables yield widely divergent body mass estimates for Chilecebus, implying that the correlations observed in a crown group cannot be assumed a priori for early diverging fossils. Variables allometrically consistent with those in extant forms yield a body mass estimate of slightly less than 600 grams for Chilecebus, nearly a factor of two smaller than prior preliminary estimates. Scaled to body mass, the brain of Chilecebus is markedly smaller than those of modern anthropoids, despite its lowered body mass estimate advocated here. This finding, in conjunction with a similar pattern exhibited by fossil catarrhines, suggests that increased encephalization arose independently in the two extant subgroups of anthropoids (platyrrhines and catarrhines)