Atractus

Abstract: Dipsadine snakes of the genus Atractus are endemic to the Neotropical region, occurring from Panama to Argentina. Currently, the taxonomic status of most species of the genus is unclear and previous attempts of taxonomic revisions have been local in scale. In this paper we evaluate the taxonomic status of the Brazilian Atlantic Forest species of Atractus based on meristic, morphometric, maxillary dentition, and hemipenis characters. Quantitative and qualitative analyses suggest the recognition of one new species (A. caete sp. nov.) from the state of Alagoas, another (A. francoi sp. nov.) from the mountainous regions of the states of Rio de Janeiro and Sao Paulo, and the synonymy of A. kangueryensis with A. thalesdelemai. Specimens previously assigned to A. taeniatus in Argentina and Brazil are here considered A. paraguayensis. A key to the Atlantic Forest Atractus is provided and three new species groups are proposed for some cisAndean Atractus, mainly on the basis of hemipenial morphology: the A. emmeli, A. maculatus, and A. pantostictus species groups.

Abstract: A new species of Atractus is described from Serra de Baturite ´, an Atlantic Forest enclave in the semiarid Caatinga of the state of Ceara ´, northeastern Brazil. The new species is distinguished from all congeners by the combination of 17 dorsal scale rows at midbody, long loreal, two postoculars, seven upper and lower labials, first four infralabials in contact with chinshields, seven maxillary teeth, moderate body and tail sizes, slightly bilobed and semicapitate hemipenis with lateral-tip projections, light dorsal color pattern uniformly scattered with small dark brown dots, and ventral color pattern uniformly creamish white. The new species shares most of the external morphology and hemipenis characters with A. pantostictus, differing from this taxon by general color pattern and number of subcaudal scales.

Abstract: A re-examination of old specimens of the genus Atractus, preserved in the Rijksmuseum van Natuurlijke Historie resulted in the discovery of syntypes of Brachyorrhos badius F. Boie, B. flammigerus F. Boie, B. schach F. Boie and Rabdosoma torquatus Dumeril, Bibron & Dumeril. Lectotypes for all these species are designated. B. flammigerus and B. schach have been considered synonyms of Atractus badius since 1837. This proved to be wrong, they turned out to be valid taxa exhibiting differences in scale counts, body size, hemipenial morphology and colour pattern. Among recently collected material from Surinam the recently described A. zidoki Gasc & Rodrigues was discovered and described on the basis of seven specimens. Both A. latifrons (Gunther) and A. favae (Filippi) are reported for the first time from Surinam. Including A. elaps (Gunther) the total number of species now known from Surinam is eight. Data gathered in Surinam indicate that the existence of many localised forms in Atractus is real and that under the name A. badius probably several other taxa are hiding. A revision of the entire genus is badly needed.