Parthenogenetic Cnemidophorus tesselatus Complex at Higbee, Colorado: Resolution of 30 Years of Controversy

Abstract

At times over 30 years, various authors have expressed conflicting opinions on the composition of the parthenogenetic Cnemidophorus tesselatus complex at Higbee, Otero County, Colorado, the only known site of sympatry between diploid and triploid members of this complex. Recently, some workers have stated that two rather than three distinctive parthenogens occur at Higbee, one being an undescribed triploid species (tentatively designated pattern class C), which resulted from hybridization between C. tesselatus D(2n) and gonochoristic C. sexlineatus. Alternatively, our study identified two diploid pattern classes [C(2n) and D(2n)] and one triploid pattern class [B(3n)] among specimens of C. tesselatus from Higbee (including those with electrophoretically determined ploidy levels). We used two canonical variate analyses (CVA) to test hypotheses concerning the identity and origin of the triploid form. CVA1 suggested that specimens of the Higbee triploid form represented C. tesselatus B(3n), not an undescribed species. CVA2 suggested that C. tesselatus B(3n) was derived from a C. tesselatus C(2n) x C. sexlineatus hybrid, not a hybrid involving C. tesselatus D(2n).