Systematics of Cnemidophorus gularis. II. Specific and Subspecific Identity of the Zacatecas Whiptail (Cnemidophorus gularis semiannulatus)

Abstract

gularis and populations previously allocated to C. scalaris pallidus and C. scalaris semifasciatus are actually conspecific, with the appropriate nomenclatural combinations being C. g. gularis, C. g. pallidus and C. g. semifasciatus. Analyses of specimens from southern Durango, Zacatecas, Aguascalientes and San Luis Potosi provide additional evidence that all populations previously allocated to C. s. scalaris are actually conspecific with C. gularis. C. gularis scalaris is currently the only available name for what is actually a number of highly distinctive geographic variants which occur in parts of Chihuahua, Durango, Zacatecas, Aguascalientes, San Luis Potosi, Nuevo Leon, Tamaulipas, Queretaro, Guanajuato, Michoacan and Jalisco. Specific recognition is herein accorded to one of these geographic variants which occurs in most of Zacatecas and adjacent parts of southern Durango, extreme western San Luis Potosi and extreme northern Aguascalientes between elevations 1,981-2,819 m. C. gularis semiannulatus (n. ssp.) is characterized by a maximum snout vent length of about 104 mm, 84.4 granules around midbody, 197.0 granules from occiput to rump, 34.7 femoral pores, circumorbital scales which extend anteriorly to the middle of the third supraocular scales, plate-like postantebrachial scales, enlarged mesoptychial scales; juvenile pattern of six vivid stripes and numerous minute spots; adult pattern of sharply defined grayish to yellowish middorsal spots and/or bars, stripes absent (adult males) or occasionally fused with spots and bars (adult females); ventral pattern consisting of a vivid reddish-pink suffusion. Adults of both sexes of C. g. semiannulatus attain sexual maturity at a snout vent length of about 55 mm. Average clutch size based upon oviducal eggs and yolked ovarian follicles in 22 females was 4.68 (range 37).