Geographic range: Nearctic, Neotropical: S. grammicus is native to extreme south US (Texas) and Mexico (states of Chihuahua, Coahuila, Nuevo Leon, Tamaulipas, Veracruz, Durango, Zacatecas, San Luis Potosi, Jalisco, Guanajuato, Queretaro, Hidalgo, Colima, Michoacan, Estado Mexico, Morelos, Puebla, Oaxaca, Guerrero and Federal District).

Physical characteristics: Medium sized (10 -17.5 cm) lizard of mottled olive to gray color. The dorsal pattern consists of 3-6 dark crossbars in uneven, or wavy pattern. Narrow crossbars can be seen also on forelegs and tail. Dorsal pattern may be more obvious in females. Females are also larger than males. Males have blue patches and black mottling on throat, a dark line on each shoulder, and blue patches on sides of belly, which may be bordered in black. Dorsal scales are keeled.

Food habits: Principal food items include insects (Coleoptera, Hymenoptera, Diptera, Lepidoptera, Hemiptera...) but plant matter is also consumed.

Reproduction: S. grammicus is viviparous. Males' testicles show peak of activity in spring, from March to July, vitelogenesis in females occurs from July to September. 3 to 7 young per female are usually born after 8 months gestation period in next year's spring.

Behavior: Very wary diurnal lizard and will retreat up the tree or other shelter when threatened. On sunny days can be observed from around 9 AM till 4 PM.

Habitat: Usually found in trees, S. grammicus can also be found on rocks, boulders, fallen tree trunks, ect. in a wide variety of arid and semi -arid environments, from forested areas to bare mountain slopes.

Biomes: temperate forests, mountains