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Deterioration of amber.
No full text19 p. : ill. (chiefly col.) ; 26 cm.The deterioration of fossil resins (crazing, cracking, and darkening) was investigated by comparing the effects of one year of accelerated aging--specifically intensive exposure to light, heat, and fluctuating humidity, both individually and in combination--on samples from several natural resin deposits. These included two Cretaceous ambers (from Myanmar (Burma) and central New Jersey), two Tertiary ambers (from the Baltic and the Dominican Republic), and Holocene copal from Zanzibar. The five resins were chosen for their disparate ages and botanical origins (and thus chemical and physical properties), as well as their paleontological significance. In all cases, pronounced deterioration occurred under combined exposure to light and fluctuating humidity, based on surface crazing and a decrease in absorbance of light in the UV region (360-400 nm). While crazing did not visibly occur in cases of fluctuating humidity in dark conditions, or UV exposure alone, spectrophotometric evidence indicates that some deterioration did take place. Yellowing after exposure to elevated temperatures occurred in all samples tested, with the exception of Burmese amber. All four true ambers exhibited a decrease in UV absorbance after exposure to heat (while copal actually showed an increase). The samples from the five deposits represent three chemical subclasses of fossil resins, and each of the resins reacted differently to the various aging conditions, with New Jersey amber particularly unstable. Based on these results, amber collections should be stored in an environment with stable humidity, relatively low heat, and minimal exposure to light. Anoxic sealing and storage, and particularly embedding amber samples in a high-grade epoxy, may be beneficial, and further investigation is indicated
The goblin spider genus Ischnothyreus (Araneae, Oonopidae) in the New World. (American Museum novitates, no. 3759)
No full text32 p. : ill. (some col.) ; 26 cm. Part of the oonopid PBI project. Cf. acknowledgments.Although originally described from St. Vincent in the Lesser Antilles, the goblin spider genus Ischnothyreus Simon appears to be an Old World taxon that is represented in the New World only by two presumably introduced, pantropical, synanthropic species: I. peltifer (Simon) and I. velox Jackson. Two specific names based on New World specimens (I. barrowsi Chamberlin and Ivie from Florida, and I. indressus Chickering from the Lesser Antilles) are placed as junior synonyms of I. velox, which is newly recorded from Mexico, Panama, Jamaica, Hispaniola, Venezuela, Brazil, Madagascar, the Philippines, the Marshall Islands, Hawaii, the Marquesas Islands, and New Caledonia. A third species, I. browni Chickering, that is supposedly from Costa Rica was apparently based on mislabeled specimens that are actually from the Philippines. The type specimens of I. browni resemble those of the Seychelle species Ischnothyrella jivani (Benoit) in that the dorsal abdominal scutum of males is extremely weak and that of females is either greatly reduced or entirely lost. Both species nevertheless share the synapomorphies of Ischnothyreus, and the generic name Ischnothyrella Saaristo is therefore placed as a junior synonym of Ischnothyreus
AMNH type specimens Emberizidae.
No full text125 p. ; 26 cm. Pts. 1-3 & 5-9 issued as v. 150, article 3 (1973), v. 161, article 1 (1978), no. 257 (2000), no. 278 (2003), no. 292 (2005), no. 313 (2008), no. 333 (2010) and no. 348 (2011) of Bulletin of the American Museum of Natural History; pt. 4 issued as no. 2879 (1987) of American Museum novitates.This tenth part of "Type specimens of birds in the American Museum of Natural History" includes taxa in the family Emberizidae in volume 13 of Peters' Check-list of birds of the world (Paynter, 1970a). The original description of each taxon has been consulted and the currently accepted name of the taxon has been listed with reference to Dickinson (2003). In a few cases, more recent studies have been taken into account. Modern names and coordinates of type localities are given when possible and comments on taxonomic history are provided. In this part, 338 names are treated; types of 19 of these are not in AMNH or were not found. This part of the type list, as well as all previous parts, are searchable and available for download from the AMNH Library website: http://digitallibrary.amnh.org/dspace/
Comparative morphology of the internal nasal skeleton of adult marsupials based on X-ray computed tomography. (Bulletin of the American Museum of Natural History, no. 365)
No full text91 p. : ill. (some col.) ; 26 cm.The internal skeleton of the nasal cavity is sporadically and often incompletely described for many marsupial species and mammals in general. Here, I provide an anatomical survey of the ethmoid in the skulls of adult marsupials based on examination of computed tomography (CT) imagery of 29 taxa representing all the major extant groups of marsupials. This survey resulted in a description of the "generalized condition" for the morphology of the marsupial ethmoid bone, ossified nasal septum, and associated structures of the interior of the nasal cavity. I also described how the ethmoid in different clades varies in morphology from the general condition for Marsupialia. Intraspecific variation of the ethmoid was described based on a sample of 18 specimens of Monodelphis domestica, the gray short-tailed opossum, and asymmetries within a single specimen are documented for other taxa. For the most part I follow the nomenclature of previous nasal cavity workers, but I also provide explicit definitions of all the terms used and some of the common synonyms for these in the literature. Endoturbinals and ectoturbinals are numbered sequentially following the work of previous authors, because of the issues with serial homology for these elements. The number of elements of the marsupial ethmoid is fairly conserved with the typical and likely ancestral condition being the presence of an ossified maxilloturbinal, nasoturbinal, two ectoturbinals, and five endoturbinals. However, there is considerable variation in the complexity, spatial placement, and overall morphology of the bony internal skeleton of the nose. Based on this descriptive work, I documented 35 discrete characters from the ethmoid and ossified nasal septum complex in marsupials. These characters were scored for this sample of marsupials and five mammalian outgroups. Examination of these characters on preexisting topologies of marsupial relationships revealed some phylogenetic signal for this sample of marsupial species. Three of the characters are punitively diagnostic for previously recognized clades within Marsupialia. It is possible that when this matrix is combined with morphological data from other anatomical systems and molecular data that previously unrecognized or controversial clades within Marsupialia may be supported. Even so, the relatively little amount of phylogenetic signal from my character matrix prompted me to search for alternative explanations for mechanisms driving the variation in this anatomical system. Consequently, I compared ecological data with the number of ecto- and endoturbinals as a preliminary test to determine whether some of the interspecific variation in the osteology of the ethmoid is a result of ecological factors, but found few correlations to support this idea. Finally, my study highlights some issues with homologies of mammalian nasal cavity elements that need to be resolved and reexamined. These include whether the ossified nasal septum arises from the presphenoid or the mesethmoid, and a test of the current view of serial homology of the endoturbinals and ectoturbinals
New species of Allophrynidae.
No full text17 p. : ill. (some col.), col. map ; 26 cm.We describe Allophryne resplendens, a new species from two localities in the Amazon rainforest of Loreto, Peru, of the family Allophrynidae, which was monotypic until this discovery. The new species can be readily differentiated from Allophryne ruthveni on the basis of dorsal and ventral coloration both in life and in preservative, transverse processes of presacral II oriented anterolaterally (oriented laterally in A. ruthveni), 19 nucleotide autapomorphies for 761 base pairs (bp) of the mitochondrial gene 16S, and 16 for 923 bp of 12S. Maximum parsimony analysis of the mitochondrial gene 12S and a fragment of up to 1060 bp of 16S supports the new species as sister to A. ruthveni
DNA identification of sharks and rays.
No full text262 p. : ill. (some col.) ; 26 cm.In an effort to provide a framework for the accurate identification of elasmobranchs, driven in large part by the needs of parasitological studies, a comprehensive survey of DNA sequences derived from the mitochondrial NADH2 gene was conducted for elasmobranchs collected from around the world. Analysis was based on sequences derived from 4283 specimens representing an estimated 574 (of ̃1221) species (305 sharks, 269 batoids), each represented by 1 to 176 specimens, in 157 (of 193 described) elasmobranch genera in 56 (of 57 described) families of elasmobranchs (only Hypnidae was not represented). A total of 1921 (44.9%) of the samples were represented by vouchers and/or images available in an online host specimen database (http://elasmobranchs.tapewormdb.uconn.edu). A representative sequence for each of the 574 species identified in this survey, as well as an additional 11 sequences for problematic complexes, has been deposited in GenBank. Neighbor-joining analysis of the data revealed a substantial amount of previously undocumented genetic diversity in elasmobranchs, suggesting 79 potentially new taxa (38 sharks, 41 batoids). Within-species p-distance variation in NADH2-percent sequence divergence ranged from 0 to 2.12 with a mean of 0.27; within-genus p-distance variation ranged from 0.03 to 27.01, with a mean of 10.16. These values are roughly consistent with estimates from prior studies based on barcode COI sequences for elasmobranchs and fishes. While biogeographic influences have likely shaped the diversification of the entire group, the traces left by older influences tend to be overprinted by newer ones. As a result, the most clearly interpretable influences are those associated with recently diverged taxa. Among closely related elasmobranchs, four regions appear to be of particular importance: (1) the Atlantic Ocean, (2) Arabian Sea, Persian Gulf, and Red Sea, (3) Southeast Asia, and (4) Australia. Each of these regions has a substantial proportion of taxa that are genetically distinct from their closest relatives in other regions. These results suggest that great care should be taken in establishing the identities of elasmobranch hosts in parasitological studies. Furthermore, it is likely that many existing host records require confirmation
Scaphioides and Hortoonops.
No full text62 p. : ill. (some col.) ; 26 cm.The genus Scaphioides Bryant contains species that resemble those of Stenoonops Simon but lack the sternal and palpal synapomorphies of that genus and have a longitudinal ridge on the male endites, a short, wide male embolus, and a more heavily sclerotized epigastric scutum in females. As delimited by those characters, the genus is circum-Caribbean in distribution and contains at least 19 species, including 11 described as new: S. campeche from the Yucatan peninsula of Mexico, S. irazu from Costa Rica, S. bimini and S. gertschi from the Bahama Islands, S. camaguey, S. granpiedra, S. siboney, S. cobre, and S. yateras from Cuba, S. miches from Hispaniola, and S. reductoides from the Virgin Islands. The male of S. halatus (Chickering) is described for the first time. A new genus, Hortoonops, is established for three similar Caribbean species that lack the synapomorphies of both Stenoonops and Scaphioides, but are united by peculiar excavations on the anterior metatarsi that represent an extraordinary convergence with the structures found in the African corinnid genus Hortipes Bosselaers and Ledoux. Stenoonops lucradus Chickering from the Virgin Islands and Stenoonops portoricensis Petrunkevitch from Puerto Rico are transferred to Hortoonops, and a new species, H. excavatus, is described from Hispaniola
Archboldomys reconsidered.
No full text60 p. : ill., maps ; 26 cm.Shrew mice of the genus Archboldomys are poorly known members of an endemic clade of vermivorous/insectivorous murid rodents confined to Luzon Island, Philippines. Three species of these small, ground-living, diurnal mice were previously known, all from a handful of specimens from a few localities. The pattern of morphological and genetic differentiation among additional specimens of shrew mice from our recent field surveys in the Central Cordillera and Sierra Madre mountains of Luzon document the presence of two distinct species groups within Archboldomys as previously defined, as well as three new species. Gene-sequence data from the mitochondrial cytochrome b and nuclear IRBP genes confirm the existence of six distinct species, but also show that Archboldomys, as previously defined, is composed of two clades that are not sister taxa. Reevaluation of the presumed morphological synapomorphies among these shrew mice, together with analyses of karyological and gene-sequence data, support the following: (1) erection of Soricomys, new genus; (2) transfer of A. kalinga and A. musseri to Soricomys; and (3) recognition of Archboldomys maximus, n. sp., Soricomys leonardocoi, n. sp., and Soricomys montanus, n. sp. The new genus and species are described, and their phylogenetic relationships, biogeography, and conservation are discussed
Fossil Curtonotidae (Diptera, Schizophora, Ephydroidea). (American Museum novitates, no. 3760)
No full text16 p. : ill. (some col.) ; 26 cm.Curtonotidae are a small, mostly tropical family of acalyptrate flies in the Ephydroidea, a superfamily that also includes the Drosophilidae. Two species of Curtonotidae are described from Miocene amber of the Dominican Republic, 17-20 Ma: Curtonotum [dagger]electrodominicum Grimaldi and Kirk-Spriggs, sp. n., and Depressonotum [dagger]priscum Grimaldi and Kirk-Spriggs, gen. et sp. n. The fossil Curtonotum is based on a female specimen and has some features of Neotropical species and a small clade of African species. Depressonotum priscum, gen. et sp. n., is based on a male and female and has a unique combination of features that are plesiomorphic and derived for the Curtonotidae. These are the only definitive fossils of the family and the only Curtonotidae known from the Caribbean. The fossil Curtonotidae provide rare data on the geological occurrence of ephydroid flies, essential for estimates of divergence times