Two new species of Atractus from Colombia (Reptilia, Squamata, Dipsadidae)

Abstract

We describe two new species of Atractus from Colombia: one from the Serrania de la Lindosa, south of San José de Guaviare in the province Guaviare, and another from Punta de Betin in the province Magdalena, close to the Caribbean coast. The first new species differs from all congeners by having a combination of 17 smooth dorsal scale rows; loreal present, approximately as long as high; temporals 1+2; seven supralabials; seven infralabials; five maxillary teeth; four gular scale rows; four pre-ventrals; 187 ventrals in single male; 29/31 subcaudals in single male; dorsum of body with longitudinal stripes; venter uniformly dark gray. The second new species differs from all congeners by having a combination of 17 smooth dorsal scale rows; loreal absent; temporals 1+2; seven supralabials; six or seven infralabials; eight maxillary teeth; three gular scale rows; three pre-ventrals; 146 ventrals in single male; 31/32 subcaudals in single male; dorsum of body and tail reddish brown with paired, occasionally slightly alternating lateral vertical cream blotches, approximately one dorsal scale broad, not contacting in vertebral region; venter cream with reddish brown blotches, forming two parallel series on anterior body and a checkered pattern on the rest of body.

Morphological variation in Atractustartarus (Serpentes: Dipsadidae) from the Xingu River, east Amazon, Brazil and preliminary phylogenetic relationship in Atractus

“…All other measures were taken with the help of a digital caliper 0.01mm of the brand Mitutoyo (R) . Morphological descriptions and type of cephalic scales follow the literature [4,14,15]. The measurements of the structures pairs, were performed on the left side of the body [15].…”

“…The taxonomy of this genus has long been based on external morphological characters as coloration pattern and cephalic plates [4,5,10], recently being incorporated data as hemipenis [7,3]. In the last decade, many species have been described based on traditional morphological characteristics and/or hemipenis: Brazil [11,12,13,14], Colombia [15] and Ecuador [16]. With respect to hemipenis, [4] defined two forms of this structure to Atractus Ecuador: 1) undifferentiated, entirely covered with small spines willing in longitudinal lines; 2) differentiated with the center of the body forming two areas, one distal and another basal.…”