[Herpetology • 2016] Amphisbaena filiformis • A New Two-pored Species of Amphisbaena (Squamata, Amphisbaenidae) from the Brazilian Cerrado, with A Key to the Two-pored Species of Amphisbaena

Amphisbaena filiformis 

Ribeiro, Gomes, Silva, Cintra & Silva, 2016

  DOI: 10.11646/zootaxa.4147.2.2   

Abstract

A new species of Amphisbaena is described from municipalities of Babaçulândia, State of Tocantins, and Estreito, State of Maranhão, northern Brazilian Cerrado. The new species differs from other two-pored species of the genus, by presenting mainly slender body shape; snout rounded in profile and dorsal view; high number of body annuli (328–342); 12–14 dorsal segments and 14–16 ventral in midbody half-annulus; autotomic site between 9–10th caudal annuli; absence of chevron-shaped anterior dorsal half-annuli; 20–23 caudal annuli; postmalar row absent; and precloacals pores arranged in a continuous series of the precloacal half-annuli. Additionally, we present a key for two-pored species of Amphisbaena.

Keywords: Reptilia, Amphisbaenia, morphology, dicotomic key, taxonomy

FIGURE 6.  Amphisbaena filiformis sp. nov. in life (not identified specimen of type series) from Babaçulândia municipality, State of Tocantins, Brazil.

Photo by C.E.D. Cintra 

Diagnosis. (1) snout rounded; (2) 328–342 body annuli; (3) absence of major fusion of head shields, being shields of dorsal, lateral and ventral head portion distincts; (4) two precloacal pores; (5) 12–14 dorsal and 14–16 ventral segments per midbody annulus; (6) autotomic site between 9–10th caudal annuli; (7) absent of chevron- 126 RIBEIRO ET AL. · Zootaxa 4147 (2) © 2016 Magnolia Press shaped anterior body annuli; (8) precloacals pores arranged in a continuous series of the precloacal half-annuli; (9) 20–23 caudal annuli; (10) distinct dorsal sulci; (11) head slightly thiner than trunk; (12) tail tip slightly compressed; and (13) postmalar row absent. 

Etymology. The specific epithet filiformis is formed from the Latin words filum (= thread) and forma (= shape) in reference to the slender body shape characteristic of the new species.

Distribution and habitat. Amphisbaena filiformis has been collected only in Babaçulândia and Estreito municipalities, States of Tocantins and Maranhão, respectively, in the northern Brazilian Cerrado (Fig. 1). The specimens from Babaçulândia municipality were collected in the left margin of the Corrente river, and the specimens from Estreito municipality were collected in the right margin of the Tocantins river on sandy soil. Babaçulândia and Estreito municipalities are located in a complex phytogeographic region, with three distinct vegetational formations: open lowland rainforest (floresta ombrófila aberta de terras baixas), seasonal forest (floresta estacional), and Cerrado. However, on the margins of Corrente river and Tocantins river, the main vegetational formation is the open lowland rainforest, locally characterized by the babaçu palm tree (Attalea speciosa Mart. ex. Spreng). The large presence of this species in a region is known as "palm forest" (Fig. 7) (IBGE 1992). It was in this vegetation that the specimens of A. filiformis were found. 

Ribeiro, Síria, Jerriane O. Gomes, Helder L. R. D. Silva, Carlos E. D. Cintra and Nelson J. Da Silva Jr. 2016. A New Two-pored Species of Amphisbaena (Squamata, Amphisbaenidae) from the Brazilian Cerrado, with A Key to the Two-pored Species of Amphisbaena.
Zootaxa. 4147(2); 124–142.  DOI: 10.11646/zootaxa.4147.2.2 

Resumo: Uma nova espécie de Amphisbaena é descrita dos municípios de Babaçulância, estado do Tocantins, e Estreito, estado do Maranhão, no norte do Cerrado brasileiro. A nova espécie difere das outras espécies do gênero com dois poros principalmente por apresentar forma do corpo delgada, focinho arredondado em vistas dorsal e de perfil; alto número de anéis corporais (328–342); 12–14 segmentos dorsais e 14–16 ventrais em um anel do meio do corpo; anel autotômico entre o 9o e 10o anel caudal; ausência de anéis corporais em forma de “V” na parte anterior do corpo; 20–23 anéis caudais; fileira de pós-malar ausente; e poros pré-cloacais arrajandos em uma série continua do meio anel pré-cloacal. Adicionalmente, nós apresentamos uma chave para as espécies de Amphisbaena com dois poros. 

Palavras chave: Amphisbaenia, morfologia, chave dicotômica, taxonomia