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Proceedings of the Third Caldwell Conference, St. Catherines Island, Georgia, May 9-11, 2008
No full text341 p. : ill. (some col.), maps (some col.) ; 26 cm.
"Issued June 23, 2010."
Includes bibliographical references (p. 303-341).The late Archaic of the American Southeast is typically described as a time of population growth, innovative developments in subsistence strategies, and increased social complexity. Although it is difficult to generalize, many early Woodland communities are characterized as relatively small scale, fairly mobile foragers organized into unranked or minimally ranked lineages and clans. Early Woodland groups also seem to be more socially isolated than their late Archaic predecessors, with a decline in regional exchange networks. The papers in this volume were presented at a conference entitled "What Happened in the Late Archaic?" which was co-sponsored by the American Museum of Natural History and the St. Catherines Island Foundation and held on St. Catherines Island (Georgia), May 9-11, 2008. The Third Caldwell Conference invited the participants to engage the appropriate archaeological data from the American Southeast, specifically addressing the nature of change during the late Archaic-early Woodland transition. This volume consists of a dozen substantive papers, followed by three discussant contributions.
TABLE OF CONTENTS: Trend, tradition, and transition at the end of the Archaic / Tristram R. Kidder -- "Nothing but the river's flood" : late Archaic diaspora or disengagement in the lower Mississippi Valley and southeastern North America / Jon L. Gibson -- The two rings of St. Catherines Island : some preliminary results from the St. Catherines and McQueen shell rings / Matthew C. Sanger and David Hurst Thomas -- Two late Archaic period shell rings, St. Simon's Island, Georgia / Rochelle A. Marrinan -- The Archaic above Choctawhatchee Bay : hydrodynamics, adaptation, and abandonment / Rebecca Saunders -- Prehistoric landscapes of complexity : Archaic and Woodland period shell works, shell rings, and tree islands of the Everglades, South Florida / Margo Schwadron -- Shell rings and other settlement features as indicators of cultural continuity between the late Archaic and Woodland periods of coastal Florida / Michael Russo -- "What happened to the southeastern Archaic?" : a perspective from St. Catherines Island / David Hurst Thomas -- Leaving the rings : shell ring abandonment and the end of the late Archaic / Matthew C. Sanger -- The rhythms of space-time and the making of monuments and places during the Archaic / Victor D. Thompson -- Getting from the late Archaic to early Woodland in three middle valleys (those being the Savannah, St. Johns, and Tennessee) / Kenneth E. Sassaman -- Late Archaic? : what the hell happened to the middle Archaic? / Joe Saunders -- Thoughts on the late Archaic-early Woodland transition on the Georgia and South Carolina coasts / Chester B. DePratter -- Mounds, middens, and rapid climate change during the Archaic-Woodland transition in the southeastern United States / William H. Marquardt -- The end of the southeastern Archaic : regional interaction and archaeological interpretation / David G. Anderson
Oil-collecting bee Ctenoplectra cornuta.
No full text14 p. : ill. ; 26 cm.
"October 22, 2010."The mature oocyte, all five larval instars, and the pupa of Ctenoplectra cornuta Gribodo are described based upon specimens from Taiwan. Its mature larva though larger is compared with, and found similar to, that of the African Ctenoplectra armata Magretti, the only other larval ctenoplectrine studied to date. The egg index was similar to that of the African C. albolimbata Magretti. Although Ctenoplectra shares certain larval and pupal similarities with Tetrapedia (Tetrapediini), a broader study including representatives of all apine tribes needs to be considered for evaluating tribal relationships
Washington leech collections.
No full text14 p. : ill., map ; 26 cm.
"December 7, 2010."An assessment of the hirudinifauna of Washington State is presented. In total, 11 distinct leech species were found representing two new records for the state and two new species of the genus Placobdella, both described herein. Placobdella kwetlumye, n. sp., and Placobdella sophieae, n. sp., both collected in Squires Lake, Whatcom County, are morphologically similar to P. burresonae and P. pediculata respectively, but exhibit morphological features that readily separate them from congeners. In addition to the descriptions of the new species, here we provide a brief summary of the morphological traits possessed by each species found
Biology of cleptoparasitic Coelioxys chichimeca.
No full text26 p. : ill. ; 26 cm.
"March 4, 2010."
Includes bibliographical references (p. 25-26).Herein we investigate the behavior and anatomy of all larval instars of the cleptoparasitic bee, Coelioxys (Cyrtocoelioxys) chichimeca Cresson. The species is found in Central America with its host, Centris (Heterocentris) bicornuta Mocsáry, one of the cavity-nesting members of the genus. The egg/mature oocyte of C. chichimeca, unusually small (like known eggs of other Coelioxys), is described, as is egg placement in the wall of the brood chamber. The anatomy and behavior of each of the five larval instars is described. The first instar develops within the egg chorion, from which the second instar emerges. The second and third instars apparently normally remain attached by their posterior ends either to the egg chorion or to the place where the egg had been attached to the cell wall. The second instar possesses an array of large spines on the outer surface of each mandible thought to rupture the thick chorion, thus allowing eclosion. Both second and third instars have modified head capsules and mandibles enabling them to attack host immatures. Both instars possess an extremely large pair of spiracles on the eighth abdominal segment and lesser-enlarged spiracles on the two preceding abdominal segments as well as enlarged internal lateral tracheal trunks. These modifications are likely related to the need for the larva to acquire air from the substrate while the body is submerged in nectar. Fourth and fifth instars, no longer attached to the substrate, assume the morphological attributes and behavior of normal provisions-consuming megachilid larvae. The last larval instar defecates and afterwards spins a cocoon bearing a conspicuous nipple. A male pupa is also illustrated and described
Braincase in the shark Tribodus limae.
Get PDF70 p. : ill. (some col.) ; 26 cm.
"March 4, 2010."
Includes bibliographical references (p. 67-70).The braincase of the Lower Cretaceous hybodont shark Tribodus limae is examined using high-resolution CT scanning, and its internal and external morphology is described based on three-dimensional digital reconstructions. This study represents the first in-depth examination of a hybodont braincase using CT scanning and digital imaging technology. The braincase of an additional Lower Cretaceous hybodont, Egertonodus basanus, is also digitally reconstructed and compared to Tribodus. A reconstruction of cranial nerves and blood vessels in Tribodus is presented on the basis of preserved foramina. The braincase of Tribodus shares many features with those of Egertonodus and neoselachians, providing further support for the sister-group relationship between hybodonts and extant elasmobranchs. CT scans confirm that in both Tribodus and Egertonodus the glossopharyngeal and vagus canals converge and exit from a common foramen (also found in Chlamydoselachus). In both of the hybodonts examined, the trochlear nerve exits the braincase anterior to the optic nerve, a possible hybodont synapomorphy. Separate foramina for the two rami of the octaval nerve are present in both Tribodus and Egertonodus, and may represent an additional hybodont synapomorphy. Also, both taxa have three separate foramina for the trigeminal, facial, and anterodorsal lateral line nerves, apparently including an individual foramen for the superficial ophthalmic complex. However, the basicranial arterial system in Tribodus differs considerably from that of Egertonodus in that in the former the internal carotid arteries enter the braincase much farther posteriorly and through paired foramina rather than a single median foramen. The median ventral basicranial process in Tribodus is similar in structure and position to median ventral processes seen in some extant neoselachians (e.g., Etmopterus) and in embryonic Torpedo (although in the latter this structure disappears during development), and thus may have had a similar ontogenetic origin
Incisivosaurus gauthieri osteology.
No full text35 p. : ill., 1 map ; 26 cm.
"June 25, 2009."
Includes bibliographical references (p. 32-35).We provide a description of the holotype skull of the unusual oviraptorosaur Incisivosaurus gauthieri. Previous phylogenetic analyses have placed this taxon firmly within Oviraptorosauria near the base of the clade; however, until now only a cursory description of this important specimen was available. The presence of many primitive characteristics (e.g., maxillary and dentary teeth as well as an extended palate and rostrum) indicates that the observed similarities between avians and derived oviraptorids are convergences rather than shared derived characters. In addition, we clarify previous descriptions of several ambiguous anatomical features, most notably of the palate. We also employ computed tomographic (CT) analysis, which allows for a more complete description of the braincase and the reconstruction of an endocranial endocast. CT imagery reveals features that were before unobtainable, such as the presence of a replacement tooth behind the large rodentiform incisor in the premaxilla. This arrangement indicates that although the incisiform teeth of I. gauthieri are morphologically distinct they are replaced in typical archosaurian fashion.American Museum of Natural History
Goblin spiders Opopaea and Epectris.
Get PDF43 p. : ill. ; 26 cm.
"June 25, 2009."
Includes bibliographical references (p. 42-43).Although the type species of the widespread, speciose, and abundant goblin spider genus Opopaea Simon was initially described from St. Vincent in the Lesser Antilles, and 15 additional New World taxa have since been assigned to the genus, we hypothesize that Opopaea is not native to the New World, and is represented in America only by introduced species that, although now pantropical in distribution, are of Old World origin. Myrmecoscaphiella Mello-Leitão is placed as a junior synonym of Opopaea, and its type species, M. borgmeyeri Mello-Leitão from Brazil, is newly synonymized with O. concolor (Blackwall), as are also O. devia Gertsch from Texas, O. guaraniana Birabén from Argentina, and O. bandina Chickering from Florida. Opopaea timida Chickering, from Panama, is placed as a junior synonym of the type species, O. deserticola Simon, which is newly recorded from Mexico, Costa Rica, Bermuda, the Bahama Islands, Jamaica, Hispaniola, Puerto Rico, the Virgin Islands, Barbados, Trinidad, Colombia, and Brazil; O. concolor is newly recorded from Mexico, Costa Rica, the Bahama Islands, Cuba, Jamaica, Ecuador, the Galapagos Islands, Peru, and Hawaii. A third widespread species has most commonly been cited as O. lena Suman, originally described from Hawaii and recently chosen as the type species of the monotypic genus Nale Saaristo and Marusik. Nale is here placed as a junior synonym of Epectris Simon, as its type species is placed as a junior synonym of E. apicalis Simon, described from the Philippines; E. apicalis is newly recorded from Florida, Mexico, Panama, Ecuador, Re´union, Singapore, Borneo, Micronesia, and New Caledonia. Opopaea cupida (Keyserling) is transferred to Marsupopaea Cooke; O. recondita Chickering is transferred to Brignolia Dumitresco and Georgesco. In a supplement, Pelicinus vernalis (Bryant), described from Florida, is also placed as a junior synonym of O. concolor.American Museum of Natural History
Didelphid marsupials.
No full text177 p. : ill. (some col.) ; 26 cm.
"Issued June 30, 2009."
Includes bibliographical references (p. 142-156).This report summarizes a decade of morphological and molecular research on the phylogenetic relationships of didelphid marsupials (opossums), a substantially intact radiation of New World metatherian mammals. We review the comparative morphology of Recent opossums, emphasizing those anatomical systems from which taxonomically useful information is available for the majority of living genera and species, namely the integument, cranium, and dentition. Morphological similarities and differences among didelphids and other plesiomorphic marsupials (caenolestids, microbiotheriids, dasyurids, and peramelids) are also described. These observations, representing evolved differences in diverse functional-morphological systems, together with karyotypic information gleaned from the literature, provide the basis for coding 129 phylogenetic characters that we scored for 44 ingroup and seven outgroup taxa. Published information about the size, internal organization, chromosomal location, and physiological properties of five nuclear genes (BRCA1, DMP1, IRBP, RAG1, vWF) sequenced for this study suggest that these loci are unlinked, exist as single copies, are active in different tissues, and encode protein products with widely divergent functions. All of the sequenced fragments are long (>900 bp), free of ingroup alignment ambiguities, and translate to open reading frame. Nucleotide data from a total of 7320 aligned sites were obtained from 43 ingroup and seven outgroup taxa. Separate parsimony, likelihood, and Bayesian analyses of these six data partitions (morphology + karyotypes, five genes) resulted in highly congruent estimates of didelphid phylogeny with few examples of conflict among strongly supported nodes. Analyses of concatenated sequences and combined (nonmolecular + sequence) datasets effectively summarize all of the common signal recovered from separate analyses: a completely resolved ingroup phylogeny with high support statistics at most nodes. Remaining problems (not conclusively resolved in this study) include the position of the ingroup root and the relationships of three genera (Chacodelphys, Cryptonanus, Tlacuatzin) within their respective suprageneric clades. The history of didelphid classification is reviewed, and all previous systems are found to contain nonmonophyletic groups. A revised phylogenetic classification consistent with our analytic results includes the following higher taxa: Glironiinae (for Glironia), Caluromyinae (Caluromys and Caluromysiops), Hyladelphinae (Hyladelphys), Didelphinae (Marmosini, Metachirini, Didelphini, and Thylamyini), Marmosini (Marmosa, Monodelphis, and Tlacuatzin), Metachirini (Metachirus), Didelphini (Chironectes, Didelphis, Lutreolina, and Philander), and Thylamyini (Chacodelphys, Cryptonanus, Gracilinanus, Lestodelphys, Marmosops, and Thylamys). The probable relationships of several Neogene fossil genera are also discussed. To facilitate identifications, all Recent genera are redescribed, representative crania are illustrated, and a key is provided.American Museum of Natural History