The blunt-nosed leopard lizard (Gambelia sila) is a relatively large lizard in the family Crotaphytidae. It has a long, regenerative tail; long, powerful hind limbs; and a short, blunt snout. Adult males are slightly larger than females, ranging in size from in length, excluding tail. Females are . Males weigh , females . Although the blunt-nosed leopard lizard is darker than other leopard lizards, it exhibits tremendous variation in dorsal color and pattern. The background color ranges from yellowish or light gray-brown to dark brown, depending on the surrounding soil color and vegetation. The underside is uniformly white. It has rows of dark spots across the back, alternating with white, cream-colored or yellow bands. Gambelia sila is relatively unique among crotaphytids in that sexes cannot be distinguished by permanent coloration and patterning, but both males and females develop breeding coloration, and these colors and patterns differ markedly between them. Also, unlike almost all other crotaphytids, juvenile G. sila obtain a yellow coloring under the hind limbs and tails. The signs of yellow coloration in young G. sila might indicate that some type of signal is being sent to adult leopard lizards, although no testing has been done. Possibly the purpose of yellow coloration is to signal to adults that carriers are too small to breed, and, therefore, do not pose a competitive threat. Conversely, the bright yellow coloration of juveniles could serve as a means of avoiding predators.
