Peters' Forest Racer

description

Description (26 males, 12 females). Table 1 summarizes size, body proportions, and meristic data for Dendrophidion nuchale. Largest specimen (AMNH R- 59444) a female 1225 + mm total length (very tip of the tail missing), 782 mm SVL; largest male (AMNH R- 98239) 1208 mm total length, 748 mm SVL). Tail 37 – 40 % of total length (58 – 66 % of SVL) in males; 36 – 39 % of total length (57 – 65 % of SVL) in females. Dorsal scales usually in 17 – 17 – 15 scale rows, the posterior reduction by fusion of rows 3 + 4 (N = 15), 2 + 3 (N = 10), or loss of row 3 (N = 1) at the level of ventrals 84 – 106. Ventrals 149 – 160 (averaging 156.2) in males, 153 – 165 (averaging 159.5) in females; usually two (occasionally one) preventrals anterior to the ventrals. Anal plate single or divided (approximately equal frequencies). Subcaudals 136 – 150 (averaging 142.5) in males, 137 – 147 (averaging 141.2) in females; subcaudals 3 – 14 were single in one specimen. Dorsocaudal reduction at subcaudals 27 – 54 in males (mean 41.4), 27 – 50 in females (mean 40.2). Preoculars usually 1, postoculars usually 2, primary temporals 2, secondary temporals 2, supralabials usually 9 with 4 – 6 bordering the eye (occasi

Systematics of the Dendrophidion nuchale complex (Serpentes: Colubridae) with the description of a new species from Central America

diagnosis

Diagnosis. Dendrophidion nuchale is characterized by (1) dorsocaudal reduction from 8 to 6 occurring posterior to subcaudal 25 (range, 27 – 54); (2) anal plate single or divided (approximately equal frequencies); (3) subcaudal counts> 135 in males and females; (4) ground color of head and body brown; dark crossbands with embedded pale ocelli present on the posterior half or more of the body and tail (Fig. 1); tail not strongly differentiated in color from posterior body; (5) blackish or dark brown nuchal collar present in adults (evident or not in juveniles); (6) ventral scutes in adults usually with irregular dark anterior borders to each scale (often interrupted midventrally) and sometimes with other irregular dark flecks or spots (Fig. 1); (8) total number of enlarged spines on the hemipenis relatively few ( 25 in D. nuchale). Single anal plates occur in the D. percarinatum group only in some individuals of D. paucicarinatum. Dendrophidion boshelli has 15 midbody dorsal scale rows (17 in D. nuchale). Dendrophidion nuchale differs from species of the D. dendrophis group as follows. The three species of the D. vinitor complex (D. vinitor, D. apharocybe, D. crybelum; Cadle 2012 a)

Systematics of the Dendrophidion nuchale complex (Serpentes: Colubridae) with the description of a new species from Central America

distribution

Distribution (Fig. 3). Dendrophidion nuchale as we define it is known from coastal and interior mountain ranges and adjacent foothills of northern Venezuela, and from a seemingly disjunct population in the Serranía de Perijá of northwestern Venezuela near the Colombian border (Fig. 3, Appendix 1; Roze 1966; Lieb 1988, 1991; Natera-Mumaw 2008; note that symbols for D. nuchale and D. dendrophis are reversed in figure 1 of Natera- Mumaw 2008). The elevational range of D. nuchale in the vicinity of the Rancho Grande Biological Station (Aragua state) is 870 – 1150 m (Test et al. 1966: 37) but the elevational range overall is from <100 m (Borburata, Aragua state) to 1270 m (Hacienda Picachito; Natera-Mumaw 2008). The occurrence of Dendrophidion nuchale in the Serranía de Perijá (also referred to as the Sierra de Perijá) is documented from four specimens in the Museo de Historia Natural de La Salle (MHNLS, Caracas) collected before 1953 (Alemán 1953, as “ Dendrophidion dendrophis ”) and the species seems not to have been recorded there since. These specimens were identified as D. nuchale by James R. Dixon in 1981 (Fernando Rojas-Runjaic, personal communication) and formed the basis for su

Systematics of the Dendrophidion nuchale complex (Serpentes: Colubridae) with the description of a new species from Central America

etymology

Etymology. Nuchale is derived from the Medieval Latin noun nucha, meaning the back of the neck or nape (originally from an Arabic word meaning spinal cord, with transfer of meaning) + the adjectival ending – alis (pertaining to). It presumably is an allusion to the black nape collar of Dendrophidion nuchale. The form “ nuchalis ” (the masculine and feminine form of the adjective) is often seen in combination with Dendrophidion, but the neuter form nuchale is required in this case to agree with the Greek neuter diminutive ending – ion of the genus name.

Systematics of the Dendrophidion nuchale complex (Serpentes: Colubridae) with the description of a new species from Central America