Taxonomic revision of the Brazilian Atlantic Forest Atractus (Reptilia: Serpentes: Dipsadidae)

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 São 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.

The Female Reproductive Cycle of the Neotropical SnakeAtractus pantostictus(Fernandes and Puorto, 1993) from South-eastern Brazil

“…The genus Atractus Wagler, 1828, comprises about 130 small fossorial snake species that occur in South America (Giraudo and Scrocchi, 2002;Myers, 2003;Passos et al, 2010). Atractus pantostictus is an endemic species from Brazil (B ernils and Costa, 2012), occurring in central and south-eastern Brazil, in the states of Goi as, Distrito Federal, Tocantins, Minas Gerais and São Paulo, and inhabits areas of Cerrado and Cerrado/Submontane to Lower Montane semi-deciduous forest transition zones (Passos et al, 2010).…”

“…Atractus pantostictus is an endemic species from Brazil (B ernils and Costa, 2012), occurring in central and south-eastern Brazil, in the states of Goi as, Distrito Federal, Tocantins, Minas Gerais and São Paulo, and inhabits areas of Cerrado and Cerrado/Submontane to Lower Montane semi-deciduous forest transition zones (Passos et al, 2010). The reproductive biology of most species is poorly known, and available data are mainly from very small samples (Fernandes and Puorto, 1993;Oliveira, 1993, 1999;Cassimiro et al, 2002).…”

Redescription ofAtractus punctiventrisand Description of Two NewAtractus(Serpentes: Dipsadidae) from Brazilian Amazonia

“…suggested putative affinities of A. insipidus and A. punctiventris with other cis-Andean congeners (A. altagratiae, A. pantostictus Puorto 1993, andAtractus ronnie Passos, Fernandes, andBorges-Nojosa 2007). Passos et al (2010b) assigned the last three species to the A. pantostictus species group. However, the everted conditions of the hemipenes for A. insipidus is so far unknown (Passos et al 2013a), and the association made by was based on specimens identified tentatively as A. insipidus by Silva (1993) and Silva et al (2005;now A. boimirim).…”

“…Terminology for hemipenial descriptions follows Dowling and Savage (1960) and Zaher (1999) with a few minor adaptations. We follow Passos et al (2009e) and Passos et al (2010b) with respect to conditions of the morphological characters used in diagnosis and description. …”

“…Amaral (1933) described Atractus punctiventris based on a single specimen with 15 dorsal scale rows from Villavicencio on the piedmont of the eastern Cordillera of Colombia (¼ Sabana province from Morrone 2014). Amaral assumed that this species was phylogenetically closest to Atractus reticulatus Boulenger 1885 (a species with 15 dorsal scale rows from southern South America; Passos et al 2010b) and distinguished it from A. punctiventris by the length of symphysial, shortening of chinshields, and general color pattern. Amaral (1937) reported an additional specimen of A. punctiventris from Sonsón in the northern portion of the Central Cordillera of Colombia, but Passos et al (2009a) identified this individual as a new species (Atractus paisa Passos, Arredondo, Fernandes, and Lynch 2009).…”