A New Subspecies of Lizard, Cnemidophorus sacki, from Michoacán, México

In the rugged Tepalcatepec Valley of Michoacán, a team of herpetologists uncovered a population of whiptail lizards that didn’t quite fit the known patterns of their relatives. Their careful field surveys and examination of dozens of preserved specimens revealed a group that sits geographically between the previously described C. sacki sacki of the upper Balsas Basin and C. sacki occidentalis of Jalisco. Recognizing these differences, the author proposes a new subspecies to fill the taxonomic gap and honor the pioneering work of Dr. Richard G. Zweifel.

The new form, named Cnemidophorus sacki zweifeli, is notable for its relatively large size—males exceed 130 mm in snout‑vent length—and a distinctive mosaic of colors. Adults display a dark brown dorsal ground, light green paravertebral rows, pink throats with a blue spot, and a striking pattern of cream‑colored spots along the body. The formal description is anchored by a male holotype collected at 185 m elevation, complete with detailed measurements of scales, pores, and tail proportions.