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Wing venation of Neuropterida.
Get PDF44 pages : color illustrations ; 26 cm.The wings of insects are one of their most prominent features and embody numerous characters and modifications congruent with the variety of their lifestyles. However, despite their evolutionary relevance, homology statements and nomenclature of wing structures remain understudied and sometimes confusing. Early studies on wing venation homologies often assumed Neuropterida (the superorder comprising the orders Raphidioptera, Megaloptera, and Neuroptera: snakeflies, alderflies and dobsonflies, and lacewings) to be ancient among Pterygota, and therefore relied on their pattern of venation for determining groundplans for insect wing venation schemata and those assumptions reciprocally influenced the interpretation of lacewing wings. However, Neuropterida are in fact derived among flying insects and thus a reconsideration of their wings is crucial. The identification of the actual wing venation of Neuropterida is rendered difficult by fusions and losses, but these features provide systematic and taxonomically informative characters for the classification of the different clades within the group. In the present study, we review the homology statements of wing venation among Neuropterida, with an emphasis on Chrysopidae (green lacewings), the family in which the highest degree of vein fusion is manifest. The wing venation of each order is reviewed according to tracheation, and colored schemata of the actual wing venation are provided as well as detailed illustrations of the tracheation in select families. According to the results of our study of vein tracheation, new homology statements and a revised nomenclature for veins and cells are proposed
Neotropical club-tailed scorpions.
No full text134 pages : illustrations (some color), maps ; 26 cm.The Neotropical "club-tailed" scorpions of the genus Rhopalurus Thorell, 1876, and two related genera in family Buthidae C.L. Koch, 1837, i.e., Physoctonus Mello-Leitão, 1934, and Troglorhopalurus Lourenço et al., 2004, are revised, based on a simultaneous phylogenetic analysis of 90 morphological characters and 4260 aligned DNA nucleotides from three mitochondrial and two nuclear gene loci. The monophyletic New World buthid subfamily Rhopalurusinae Bucherl, 1971, to which these scorpions were originally assigned, is redefined, revised diagnoses and a key to identification of its genera and species (except for Centruroides Marx, 1890) provided, and their distributions mapped. The paraphyly of Rhopalurus Thorell, 1876, which comprises several monophyletic groups congruent with its disjunct distribution, justifies its relimitation and that of Troglorhopalurus Lourenço et al., 2004, the revalidation of Heteroctenus Pocock, 1893, and creation of Ischnotelson, gen. nov. (type species: Rhopalurus guanambiensis Lenarducci, Pinto-da-Rocha and Lucas, 2005) and Jaguajir, gen. nov. (type species: Rhopalurus agamemnon C.L. Koch, 1839). Ten new combinations are proposed: Heteroctenus abudi (Armas and Marcano Fondeur, 1987), comb. nov.; Heteroctenus bonettii (Armas, 1999), comb. nov.; Heteroctenus garridoi (Armas, 1974), comb. nov.; Heteroctenus gibarae (Teruel, 2006), comb. nov.; Heteroctenus princeps (Karsch, 1879), comb. nov.; Ischnotelson guanambiensis (Lenarducci, Pinto-da-Rocha and Lucas, 2005), comb. nov.; Jaguajir agamemnon (C.L. Koch, 1839), comb. nov.; Jaguajir pintoi (Mello-Leitão, 1932), comb. nov.; Jaguajir rochae (Borelli, 1910), comb. nov.; Troglorhopalurus lacrau (Lourenço and Pinto-da-Rocha, 1997), comb. nov. Three new species are described: Ischnotelson peruassu, sp. nov. (type locality: Parque Estadual do Peruassu, Minas Gerias, Brazil); Physoctonus striatus, sp. nov. (type locality: Castelo do Piauí, Piauí, Brazil); Rhopalurus ochoai, sp. nov. (type locality: San Agustín, Edo. Zulia, Venezuela). Fifteen new junior subjective synonyms are proposed: Rhopalurus acromelas Lutz and Mello, 1922, Rhopalurus melleipalpus Lutz and Mello, 1922, Rhopalurus iglesiasi Werner, 1927, Rhopalurus lambdophorus Mello-Leitão, 1932, Rhopalurus dorsomaculatus Prado, 1938, and Rhopalurus goiasensis Prado, 1940 = Jaguajir agamemnon (C.L. Koch, 1839); Rhopalurus pintoi kourouensis Lourenço, 2008 = Jaguajir pintoi (Mello-Leitão, 1932); Rhopalurus crassicauda Caporiacco, 1947, Rhopalurus amazonicus Lourenço, 1986, and Rhopalurus crassicauda paruensis Lourenço, 2008 = Rhopalurus laticauda Thorell, 1876; Rhopalurus melloleitaoi Teruel and Armas, 2006, and Rhopalurus aridicola (Teruel and Armas, 2012) = Heteroctenus junceus (Herbst, 1800); Rhopalurus granulimanus Teruel, 2006 = Heteroctenus gibarae (Teruel, 2006); Rhopalurus virkii Santiago-Blay, 2009 = Heteroctenus abudi (Armas and Marcano Fondeur, 1987); Rhopalurus brejo Lourenço, 2014 = Troglorhopalurus lacrau (Lourenço and Pinto-da-Rocha, 1997)
Weevil rostrum.
No full text76 pages : illustrations (some color) ; 26 cm.The current classification of weevils has witnessed vast improvements at higher phylogenetic levels, though much remains unstable at the lower levels. In order to develop a more robust morphological character system for cladistic analysis of the higher lineages and to gain a comprehensive understanding of the structure of a hallmark feature of weevils, a comparative study was conducted of rostra throughout Curculionoidea. Semithin sections were made of the rostra of 36 exemplar genera representing all seven currently recognized weevil families, as well as 19 of 21 subfamilies within the largest family, Curculionidae, and internal structures were examined for phylogenetically informative characters. While the morphological diversity of rostral forms is impressive, general trends are apparent with respect to life-history traits and modes of feeding. Exploration of internal rostral morphology has yielded valuable but previously unexplored characters that greatly complement the external characters of this structure. Together, these features provide new insight for settling current incongruence at the higher levels of classification
Pectoral morphology in Doliodus : bridging the 'acanthodian'-chondrichthyan divide. (American Museum novitates, no. 3875)
No full text15 pages : illustrations (some color) ; 26 cm.Doliodus problematicus (NBMG 10127), from the Lower Devonian of New Brunswick, Canada (approx. 397-400 Mya) is the earliest sharklike jawed vertebrate (gnathostome) in which the pectoral girdle and fins are well preserved. Its pectoral endoskeleton included sharklike expanded paired coracoids, but Doliodus also possessed an "acanthodian-like" array of dermal spines, described here for the first time. Doliodus provides the strongest anatomical evidence to date that chondrichthyans arose from "acanthodian" fishes by exhibiting an anatomical mosaic of "acanthodian" and sharklike features
Catalog of Zalmoxes fossils.
No full text34 pages : illustrations (chiefly color), color map ; 26 cm.The Transylvanian area of Romania boasts a rich fossil record of dinosaurs, which lived on an island (Haţeg Island) during the very end of the Cretaceous. Many of these are dwarfed in body size or exhibit other unusual features thought to be linked to their insular habitat. One of the most common of these dinosaurs is the rhabdodontid ornithopod Zalmoxes, an herbivorous taxon that has been found at many Upper Cretaceous sites across Transylvania. Our collaborative fieldwork has uncovered several new Zalmoxes specimens from the Nălaț-Vad (= Vadu) locality, a site along the Râul Mare River in the Hațeg Basin that dates to the "middle" to late Maastrichtian. These include a partial associated skeleton, along with various isolated bones from several additional individuals. We catalog and describe these specimens here, and compare them to other Zalmoxes fossils from Romania. They provide further evidence that Zalmoxes was one of the most common vertebrates in the latest Cretaceous of Transylvania, and add to the unusual fossil record of Nălaț-Vad, which has yielded a much greater number of associated skeletons than other Transylvanian localities. Some of the Nălaț-Vad specimens possess features characteristic of the type species, Z. robustus, whereas others exhibit features diagnostic of the larger and stockier Z. shqiperorum, indicating that these species were locally sympatric, as has been demonstrated at other Transylvanian sites. The specimens span much of the size range known from Zalmoxes, as well as the spatial and temporal extent of the Nălaț-Vad locality, suggesting that this taxon flourished until near the end of the Cretaceous
Centris bicornuta and Epicharis albofasciata.
No full text20 pages : illustrations ; 26 cm.This paper presents detailed comparative descriptions of the mature larvae and eggs of Centris (Heterocentris) bicornuta Mocsáry and Epicharis (Epicharoides) albofasciata Smith as representatives of two genera that are closely related. It strongly suggests that both species, while developing, pass through five larval instars; because the first instar remains mostly pharate within the chorion, it is only as a second instar that it begins to consume provisions and increase in size. There follows an account of how each species changes in functional anatomy from one instar to the next and how each instar of one species compares with the same instar of the other. In response to a recently published paper (Martins and Melo, 2016), which suggested that the tribe Centridini may be polyphyletic because some taxa within Centris share features with corbiculate genera, it is pointed out that all corbiculate genera uniquely share an apomorphy: they bear small paired, elevated, finely setose, sclerotized, and usually pigmented apical tubercles on the thoracic segments of mature larvae. Such thoracic tubercles are unknown in the Centridini or elsewhere among bees
Polar bear foraging in western Hudson Bay.
Get PDF28 pages : illustrations (chiefly color), map ; 26 cm.During much of the year, polar bears in western Hudson Bay use energy-conserving hunting tactics, such as still-hunting and stalking, to capture seals from sea-ice platforms. Such hunting allows these bears to accumulate a majority of the annual fat reserves that sustain them on land through the ice-free season. As climate change has led to earlier spring sea-ice breakup in western Hudson Bay, polar bears have less time to hunt seals, especially seal pups in their spring birthing lairs. Concerns have been raised as to whether this will lead to a shortfall in the bears' annual energy budget. Research based on scat analyses indicates that over the past 40 years at least some of these polar bears eat a variety of food during the ice-free season and are opportunistically taking advantage of a changing and increasing terrestrial prey base. Whether this food will offset anticipated shortfalls and whether land-based foraging will spread throughout the population is not yet known, and full resolution of the issues requires detailed physiological and genetic research. For insight on these issues, we present detailed observations on polar bears hunting without an ice platform. We compare the hunting tactics to those of polar bears using an ice platform and to those of the closely related grizzly bear. We examine how the techniques are related and explore how they may have evolved. We also discuss how they may contribute to polar bear adaptability in the face of climate change projections
Historia de las relaciones científicas entre Cuba y el American Museum of Natural History (AMNH) : 160 años de colección y colaboración (1857-2017)
No full text132 pages : illustrations (some color), color map ; 28 cm.Spanish and English on facing pages. Includes bibliographical references (pages 123-126)
Tufa Village (Nevada) : placing the Fort Sage Drift Fence in a larger archaeological context. (Anthropological papers of the American Museum of Natural History, no. 102)
No full text63 pages : illustrations (some color), maps ; 26 cm.The Fort Sage Drift Fence is one of the largest pre-Contact rock features known in the Great Basin, and appears to date between 3700 and 1000 cal B.P. When Pendleton and Thomas (1983) first recorded the 2 km long complex, they were impressed by its sheer size and the amount of labor required to build it. This led them to hypothesize that it must have been constructed, maintained, and used by specialized groups associated with a centralized, village-based settlement system--a system that was not recognized in the archaeological record at that time. Their hypothesis turned out to be quite insightful, as subsequent analyses of faunal remains and settlement pattern data have documented the rise of logistical hunting organization linked to higher levels of settlement stability between about 4500 and 1000 cal B.P. throughout much of the Great Basin. Although Pendleton and Thomas' (1983) proposal has been borne out on a general, interregional level, it has never been evaluated with local archaeological data. This monograph remedies this situation through reporting the excavation findings from a nearby, contemporaneous house-pit village site. These findings allow us to place the drift fence within its larger settlement context, and provide additional archaeological support for the original Pendleton-Thomas hypothesis