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Auyantepui herpetofauna
No full text147 p. : ill. (some col.), map ; 26 cm.Includes bibliographical references (p. 138-147).Auyantepui is an immense sandstone table mountain in the Venezuelan Guayana. This mesa did not appear on aviation maps and was unknown to the literate world prior to the late 1930s. It was explored from the air by Jimmy Angel, a bush pilot and colorful soldier of fortune for whom the world's highest waterfall is named (Angel Falls at the northern end of Auyantepui). About the same time, in 1937, Captain Félix Cardona Puig and Gustavo Heny discovered an access crack in the sandstone, allowing ascent onto the southern end of the mesa. The first scientific exploration followed immediately--the 1937-1938 Phelps Venezuelan Expedition of the American Museum of Natural History made the first zoological and general botanical collections. Today, no tepui other than the "Lost World" of Cerro Roraima is better known to the general public. The summit of Auyantepui has a known fauna of 24 species of amphibians and reptiles, including species added by the Robert G. Goelet American Museum-TERRAMAR Expedition in 1994. This expedition collected 16 species during a month of fieldwork in the dry season (February), in five camps at elevations of 1700-2100 m above sea level. All species known from the summit of Auyantepui are treated in this bulletin; illustrations where possible include tadpoles, bioacoustic spectrograms, and hemipenes. Four new species are described--two frogs (Hypsiboas angelicus, n. sp., Eleutherodactylus auricarens, n. sp.), a lizard (Arthrosaura montigena, n. sp.), and a snake (Atractus guerreroi, n. sp.). Arthrosaura montigena possesses a hemipenial character not previously described--an orifice (orificium) of unknown function, situated in the lobular crotch between the two lobes. Attention is called to a probably undescribed snake (Liophis "miliaris" sensu lato) from the nearby Gran Sabana. The herpetofauna of the Auyán summit comprises 12 families, 20 genera, and 24 species. This is compared with the known herpetofauna of the Chimantá massif, lying less than 50 km south-southeast of Auyantepui. Despite the proximity and similar dimensions, the summits of Auyantepui and Chimantá have in common only 11% of the combined number of species (4 of 36), 44% of the genera (11 of 25), and 62% of the families represented (8 of 13), showing that neighboring tepuis may have herpetofaunas very different from one another. Nonetheless, the adjacent mountains that constitute the more fragmented Chimantá massif are relatively close to one another and seem to have a unified herpetofauna
A revision of the endemic Californian spider genus Titiotus Simon (Araneae, Tengellidae) ; American Museum novitates, no. 3608
No full text33 p. : ill. ; 26 cm.Includes bibliographical references.Titiotus Simon is revised, and contains at least 16 species known only from California. Males of the type species, T. californicus Simon, are described for the first time, as are those of T. flavescens (Chamberlin and Ivie). Eusparassus hansii Schenkel is transferred from the Sparassidae to Titiotus, and its male is newly described. Thirteen new species are described
Insects from the Upper Miocene Grubstake Formation of Alaska ; American Museum novitates, no. 3612
No full text19 p. : ill., map ; 26 cm.Includes bibliographical references (p. 17-19).Well-preserved insect wings are reported in weakly consolidated lacustrine shale from the Grubstake Formation, Upper Miocene of Suntrana Creek, central Alaska. ⁴⁰Ar/³⁹Ar dating of an immediately overlying volcanic ash indicates an age of slightly more than 6.7 ± 0.1 Ma, or approximately one million years before the opening of the Bering land bridge. The insects include four genera and two subfamilies of ants (Hymenoptera, Formicidae, Myrmicinae and Dolichoderinae), a species of Ichneumonidae (Hymenoptera), three genera and families of flies (Diptera: Chironomidae [genus indet.], Bibionidae [Bibio] and Lonchaeidae [Dasiops]), and the elytra of curculionid and carabid beetles. Extant distributions of the flies and possibly the ichneumonid include northerly latitudes around Suntrana. The ants are attributable to the extant genera Dolichoderus or Tapinoma (Dolichoderinae), Solenopsis or Erebomyrma (Myrmicinae), as well as Veromessor and Novomessor (Myrmicinae), indicating extensive biogeographic contraction to more southern latitudes of North America today. These finds are consistent with evidence from a slightly younger deposit from the uppermost Miocene (5.7 Ma) of the Seward Peninsula, Alaska. Implications are discussed regarding the differential effects of climate change and land bridges on the dispersal of various insect taxa
Redescription of the skull of Ummulisani rutgersensis Gaffney, Tong, and Meylan, 2006, a bothremydid side-necked turtle from the Eocene of Morocco ; American Museum novitates, no. 3615
No full text20 p. : ill. ; 26 cm.Includes bibliographical references (p. 20).Three skulls of Ummulisani rutgersensis are described here as an addendum to the descriptions and analyses presented in Gaffney et al. (2006a). The present paper is essentially a replacement for the Ummulisani cranial morphology text in that paper (Gaffney et al. 2006a: 447-457). The original description was based primarily on one skull, AMNH 30563, the type of Ummulisani rutgersensis. Because two previously undescribed skulls, AMNH 30569 and AMNH 30562, are more complete, they add significantly to our understanding of this taxon. However, it does not alter the results of the phylogenetic analysis by Gaffney et al. (2006a), in that Ummulisani rutgersensis remains the sister taxon to Phosphatochelys tedfordi
Distribution of Ambystoma
No full text58 p. : ill. (some col.), col. maps ; 26 cm.Includes bibliographical references (p. 24-26).Several species of mole salamanders in the genus Ambystoma are targeted by various state, provincial, and federal agencies for conservation. These salamanders have specific wetland and forested upland habitat requirements that render them vulnerable to environmental alteration. The blue-spotted salamander, Ambystoma laterale (LL) and the Jefferson salamander, A. jeffersonianum (JJ) have both been listed for protection in various parts of their ranges, but the identification of these salamanders is confusing because they often coexist with unisexual individuals that are mostly polyploid and use the sexual species as sperm donors. We used isozyme electrophoresis, blood erythrocytes, and chromosome counts in a continued effort to identify sexual and unisexual individuals in eastern North America. We examined 1377 salamanders from 118 sites in Connecticut, Massachusetts, New Jersey, New York, Pennsylvania, and Virginia. Most Pennsylvania salamanders were A. jeffersonianum (JJ) but A. laterale (LL), previously unknown from Pennsylvania, were found in that state. The two sexual species were never found together. We found diploid (LJ), triploid (LLJ; LJJ), and tetraploid (LLLJ; LJJJ; LLJJ) unisexuals. At most collecting sites, unisexuals were more numerous than sexual individuals. The association of sexual and unisexual individuals support a kleptogenic reproductive system in which the unisexuals steal genomes from their sympatric sexual sperm donors
Varanid evolution
No full text15 p. : ill. ; 26 cm.
Includes bibliographical references (p. 11-14).Saniwa ensidens is a pivotal taxon for understanding varanid evolution. A complete specimen of Saniwa ensidens was recently described, offering important new insights into the morphology of this taxon. We apply these new data to a broader-scale study of squamate relationships in order to understand the phylogenetic position of Saniwa ensidens and of varanids more generally. Among the other fossils included in our analysis were the Eocene taxon "Saniwa" feisti, the Miocene Varanus rusingensis, and the giant Pleistocene varanid Megalania prisca. We compare the phylogenetic hypothesis from our analysis of morphology with a recent molecular-based hypothesis and find numerous differences in the phylogenetic relationships within Varanus. We constrained our morphological data set to the phylogenetic pattern presented by the molecular data to further analyze the possible phylogenetic relationships of the fossil taxa. Our analyses show that Saniwa ensidens is the sister taxon to crown-group Varanus and that "Saniwa" feisti is a basal member of the varanid lineage, not closely related to Saniwa ensidens. Both Varanus rusingensis and Megalania prisca are members of the crown radiations of Varanus
Review of Leptomys
No full text60 p. : ill. (some col.), maps ; 26 cm.Includes bibliographical references (p. 56-60).Two new species of the endemic New Guinea rodent genus Leptomys Thomas, 1897, are described: L. paulus, indigenous to the montane forests in the Owen Stanley Range in eastern New Guinea, and L. arfakensis, known only from the Arfak Mountains on the Vogelkop Peninsula in western New Guinea. These descriptions are presented within a taxonomic review of Leptomys based on all known specimens in collections of the world's museums. In addition to the new species, the morphological attributes and geographic distributions of three others are documented. Leptomys elegans occurs in southcentral and southeastern New Guinea both north and south of the Central Cordillera, ranging from the Kikori River Basin in the west to the southern slopes of the Owen Stanley Range, then extending round to the north side of the Cordillera in the Maneau Range, and in the outlying highland block of Mount Victory. Leptomys signatus is recorded only from the Fly and Kikori River drainages south of the Central Cordillera. Leptomys ernstmayri is found in montane forests of the eastern Central Cordillera (Aroa River to Mt. Karimui), reaches to the outlying mountains on the Huon Peninsula and the Adelbert Range, and also occurs in the isolated Foja Mountains of far western New Guinea. Judged by variation in qualitative and morphometric external, cranial, and dental traits associated with available samples, L. arfakensis, n. sp., is likely more closely related to L. elegans and L. signatus, all with large bodies and relatively short tails, than to L. ernstmayri and L. paulus, n. sp., that are characterized, among other features, by smaller body size and relatively longer tails. There is significant phenetic divergence among the geographic samples identified here as L. ernstmayri, and additional inquiry, especially utilizing data from molecular sources, is required to determine whether this intersample variation reflects the presence of separate species, each endemic to the Huon Peninsula, Adelbert Range, Central Cordillera, and possibly the Foja Mountains, or instead represents montane variation within a single morphologically variable species
Development of the embryonic shell structure of Mesozoic ammonoids ; American Museum novitates, no. 3621
No full text19 p. : ill. ; 26 cm.Includes bibliographical references (p. 17-19).Exceptionally well-preserved embryonic shells (ammonitellae) of the early Aptian ammonoid Aconeceras cf. trautscholdi Sinzov, 1870, preserved as coprolite remains from Symbirsk, Russia, were examined with scanning electron microscopy (SEM) to investigate the developmental sequence of the embryonic shell structure. Our SEM observations reveal that these shells can be classified into the following three groups with different wall microstructure: Group 1, with a thin (ca. 5 [micro]m), double-layered shell wall, consisting of inner prismatic and outer homogeneous layers, the former of which is absent in the adapical portion and becomes thicker adorally; Group 2, with a three-layered shell wall that consists of inner prismatic, middle homogeneous, and outer prismatic layers, with tubercles on the outer layer; and Group 3, with a thick nacreous swelling (primary varix) on the anteroventral side near the aperture. The middle homogeneous layer of the embryonic shells of Group 2 is the same as the outer homogeneous layer in shells of Group 1 and may be composed of amorphous calcium carbonate (ACC). In embryonic shells of Group 3, the middle homogeneous layer is absent and there are voids instead. It may have been transformed into the inner prismatic layer or else dissolved during diagenesis. In modern Nautilus and gastropods, embryonic or larval shell development is initiated by the secretion of a cap-shaped, fully organic shell prior to the deposition of calcium carbonate. This stage is not preserved in the material examined, but probably existed in the Ammonoidea. Based on our observations and data from extant Nautilus and gastropods, we propose a model for the development of the embryonic shell structure of Mesozoic ammonoids, starting from secretion of an organic primary shell, followed by deposition of ACC and its transformation into the inner prismatic layer, and terminating in the deposition of a primary varix on the inside of the ventral and ventrolateral position of the shell just adapical of the aperture
The solitary bee Calliopsis zebrata : biological and distributional notes and descriptions of its larva (Hymenoptera, Andrenidae, Panurginae). American Museum novitates, no. 3632.
No full text12 p. : ill. ; 26 cm.
Includes bibliographical references (p. 11-12).Calliopsis (Macronomadopsis) zebrata zebrata Cresson, collected from Astragalus gracilis Nutt., is reported from central Oklahoma, the most eastern locality for those Calliopsis with yellow-banded metasomas (i.e., Nomadopsis, s.l.). A long series of males and females of C. z. bobbae Rozen, associated with Astragalus humistratus A. Gray from Flagstaff, Arizona, permits an expanded description of that subspecies, comparing it with C. z. zebrata. Presented information on its nesting biology and mating behavior shows that these features are similar to those of the other species of Macronomadopsis whose biology is known. Mature larvae of both subspecies are described for the first time and compared with each other. This shows that they are essentially identical and differ little from those of other Macronomadopsis and even Nomadopsis s.l. The first SEM pictures of any panurgine larva reveal unexpected details of integumental sculpturing. Earlier studies of adults of this species demonstrated extensive geographic variability, as do adults from Oklahoma. Additional collections of this species throughout its range are needed to analyze population boundaries
Redescription of Mimoscorpius pugnator (Butler, 1872) (Arachnida, Thelyphonida), with first description of the female. American Museum novitates, no. 3633.
No full text9 p. : ill. (some col.), map ; 26 cm.A redescription of the endemic Guatemalan whip scorpion, Mimoscorpius pugnator (Butler, 1872), including the first description of the female, new records, and natural history observations, is provided