NOVATAXA: A New Species of the Rare Dipsadid Genus Caaeteboia

 

[Herpetology • 2020] Caaeteboia gaeli • A New Species of the Rare Dipsadid Genus Caaeteboia Zaher et al., 2009 (Serpentes: Dipsadidae) from the Atlantic Forest of northeastern Brazil

Caaeteboia gaeli 

  Montingelli, Barbo, Filho, Santana, França, Gobbi & Zaher, 2020

  ppct.caicyt.gov.ar

  oeco.org.br 

ABSTRACT 

Caaeteboia is a rare and elusive monotypic genus of Neotropical snake, being one of the least known dipsadids of the Brazilian Atlantic Forest. Here, we assess the morphological and genetic diversity of this genus, comparing these results with several other genera of Xenodontinae. Our combined results revealed the presence of an unknown species from the northeastern portion of the Atlantic Forest. The new species is distributed throughout the enclaves of coastal open forests mixed with savanna-like habitat, locally known as “Floresta de Tabuleiro”, and submontane ombrophilous forests in the Brazilian states of Paraíba and Pernambuco. This new species is easily distinguished from C. amarali by its lower number of dorsal, ventral, and subcaudal scales, and a remarkable dark lateral stripe from the nostril up to the anterior third of the body. The new species extends the distribution of the genus in approximately 700 kilometers northwards, reinforcing the importance of the conservation of small remnants of Atlantic Forest in northeastern Brazil, which still harbor high levels of endemicity and diversity. 

Key words: Caaeteboia; Atlantic Forest; Taxonomy; Xenodontinae; New Species.

View of the holotype of Caaeteboia gaeli sp. nov. (MZUSP 19559).
Upper left: dorsum; bottom left: venter; Upper, middle and bottom right: dorsal, lateral and ventral views of the head, respectively. Scale bars: 10 mm for the entire specimen, and 5 mm for the head.

Coloration pattern of lateral stripes of specimens of Caaeteboia gaeli sp. nov.  (A–B), and C. amarali (C–H), arranged geographically from northeast to southern Brazil. 
A: MZUSP 19559 (Holotype), Cruz do Espírito Santo, Paraíba; B: specimen not collected, Saloá, Pernambuco; C: CZGB 2371, Uruçuca, Bahia;
D: IBSP 46140, Miracatu, São Paulo; E: IBSP 72585, Cananéia, São Paulo; F: IBSP 73202, Jacupiranga, São Paulo; G: IBSP 9907, Alexandra, Paranaguá, Paraná; and H: MNRJ R 1818, Santa Luzia, Tubarão, Santa Catarina. Scale bar: 5 mm.

A: Caaeteboia gaeli sp. nov. (CHUFPB 24395 – paratype), from municipality of Pedras de Fogo, state of Paraíba (Photo: Gentil Filho);
B: Specimen from Saloá (not collected), state of Pernambuco (Photo: Samuel Cardoso).

Caaeteboia gaeli sp. nov. 

 Caaeteboia sp. — Pereira-Filho et al., 2017: 170. 

Serpentes da Paraíba: diversidade e conservação.

Diagnosis: Caaeteboia gaeli sp. nov. is diagnosed by a slender and small body; rounded pupil; eight supralabials (fourth and fifth contacting the orbit); nine infralabials (first to fourth contacting chinshields); loreal absent (fused with prefrontals); a preocular single and wide; two postoculars; temporals 2+2/1+2, or 2+1/2+1; dorsals 15/15/15; at least 158 ventrals, 92–106 paired subcaudals; anal plate divided; continuous dark-brown lateral stripe, bordered in black, extending from nasal, to the anterior portion of body, on rows of dorsals three and four, starting to fade after the10–15th ventrals, weakening towards the end of body; posterior to parietals, “V” shaped dark-mark, extending backwards and forming a weak vertebral stripe fading posteriorly; hemipenial lobes almost completely covered with calyces and naked area restricted to the small and poorly marked lobular crotch, on the asulcate side; medial edges of lobes poorly demarcated and bordered with spines; lobular crest poorly developed, bearing small spines on its edge (Fig. 6A).

Etymology: The specific name honours Gael Hingst Zaher. GGM, FEB, GAPF, GGS, FGRF and FGG dedicate this species to the beloved son of the senior author, who sadly left us prematurely in March, 2020. 

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