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Hemipenial morphology of the South American xenodontine snakes : with a proposal for a monophyletic Xenodontinae and a reappraisal of colubroid hemipenes. Bulletin of the AMNH ; no. 240

Show simple item record Zaher, Hussam. en_US 2005-11-22T22:48:39Z 2005-11-22T22:48:39Z 1999 en_US
dc.description 168 p. : ill. ; 26 cm. en_US
dc.description Includes bibliographical references (p. 84-95). en_US
dc.description.abstract "The New World xenodontine 'colubrids' represent two immunologically distinct assemblages--the Central and South American lineages, neither of which has been well diagnosed to date. I follow this nomenclature and recognize the Central American lineage as containing 22 genera. This clade is supported by the synapomorphy of a sulcus spermaticus bifurcating within or at the base of the capitulum (Cadle, 1984; Myers and Cadle, 1994). The remaining xenodontines constitute a total of 68 presently recognized genera, of which 41 are placed in the subfamily Xenodontinae sensu stricto. The other 27 genera are considered incertae sedis, pending further research. The Xenodontinae sensu stricto are hypothesized as being monophyletic on the basis of the following hemipenial synapomorphies: (1) presence of enlarged lateral spines on the hemipenial body, and (2) two distinctly ornamented regions on the lobes, the asulcate surface bearing enlarged spinulate or papillate calyces (= body calyces). Some taxa recognized as Xenodontinae sensu stricto lack body calyces but have a nude area in the same topographical position (e.g., Psomophis, Tropidodryas). This pattern is viewed as the result of secondary loss. The rationale for this conclusion is based on the hypothesis that body calyces are merely enlarged capitular calyces of the asulcate/medial surfaces of the lobes. In the Xenodontinae, the body calyces are almost always separated from the calyces of the capitulum by a more or less developed overhang (except in a few genera). This overhang is generally retained on the hemipenes where the asulcate/medial surfaces of the lobes are nude (e.g., Psomophis), which supports the view that the body calyces were secondarily lost. Body calyces are also found on the surface of the hemipenial body in its asulcate side (e.g., Philodryas, Pseudablabes, Xenoxybelis). Because body calyces are interpreted as modified 'capitular calyces,' which are restricted to the lobular region and crotch, the presence of these structures far on the hemipenial body is here viewed as a more derived state where the body calyces extend from the lobes to the body. Various presumably monophyletic units are defined within the Xenodontinae sensu stricto. Conophis, Heterodon, and Farancia are clearly assigned to the Xenodontinae sensu stricto. The hemipenial morphology of various suprageneric 'colubrid' taxa are described and compared. The variation of some hemipenial features within the colubroid radiation, as well as their bearing on the higher level phylogeny of colubroids, is investigated"--P. 3. en_US
dc.format.extent 89932769 bytes
dc.format.mimetype application/pdf
dc.language eng en_US
dc.language.iso en_US
dc.publisher [New York] : American Museum of Natural History en_US
dc.relation.ispartofseries Bulletin of the American Museum of Natural History ; no. 240 en_US
dc.subject.lcc QH1 .A4 no.240, 1999 en_US
dc.subject.lcsh Xenodontinae -- Generative organs. en_US
dc.subject.lcsh Hemipenis -- Morphology. en_US
dc.subject.lcsh Xenodontinae en_US
dc.subject.lcsh Colubridae -- Generative organs en_US
dc.subject.lcsh Colubridae -- South America en_US
dc.subject.lcsh Colubridae -- Central America en_US
dc.subject.lcsh Snakes -- South America en_US
dc.subject.lcsh Snakes -- Central America en_US
dc.subject.lcsh Reptiles -- South America en_US
dc.subject.lcsh Reptiles -- Central America en_US
dc.title Hemipenial morphology of the South American xenodontine snakes : with a proposal for a monophyletic Xenodontinae and a reappraisal of colubroid hemipenes. Bulletin of the AMNH ; no. 240 en_US
dc.title.alternative Hemipenial morphology of xenodontine snakes en_US
dc.type text en_US

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  • Bulletin of the American Museum of Natural History
    The Bulletin, published continuously since 1881, consists of longer monographic volumes in the field of natural sciences relating to zoology, paleontology, and geology. Current numbers are published at irregular intervals. The Bulletin was originally a place to publish short papers, while longer works appeared in the Memoirs. However, in the 1920s, the Memoirs ceased and the Bulletin series began publishing longer papers. A new series, the Novitates , published short papers describing new forms.

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