Reptiles
Twin-Spotted Spiny Lizard
Sceloporus bimaculosus · also called twin-spotted spiny lizards
Basking on a patch of open desert grassland, a twin-spotted spiny lizard displays the paired dark shoulder blotches that give the species its name, sharing its narrow stretch of habitat with several other spiny lizards patterned closely enough to require a careful second look.
Overview
The twin-spotted spiny lizard, Sceloporus bimaculosus, is a robust, heavily scaled lizard native to desert grassland and adjacent scrub habitat across parts of the southwestern United States and northern Mexico. Its distinctive paired shoulder blotches, overlap with several visually similar spiny lizard relatives, and typical day-active desert lifestyle make it a representative example of the diverse Sceloporus lizard group found across the American Southwest.
A name written right on its shoulders
The twin-spotted spiny lizard wears its identifying feature in plain sight, a pair of dark shoulder blotches that settle the question of identification faster than almost any other feature on its body.
Status
Least Concern — widespread and stable across suitable desert grassland habitat throughout its range in the southwestern United States and northern Mexico.
Twin-Spotted Spiny Lizard: common questions
Why is it called the twin-spotted spiny lizard?
This species displays a pair of dark blotches on the shoulders just behind the head, a paired marking clearly visible on close inspection that gives the species its descriptive common name, distinguishing it from several other similarly patterned spiny lizard relatives sharing parts of its range.
How can you tell a twin-spotted spiny lizard from similar relatives?
This species shares parts of its range with several other similarly patterned spiny lizard relatives, so reliable identification sometimes depends on close examination of the specific shoulder blotch pattern and scale counts rather than overall appearance alone, since general body shape and colouration can look quite similar across several related species.
Where does the twin-spotted spiny lizard lay its eggs?
A female of this species lays eggs in loose, sandy soil, a substrate that provides the warmth and moisture conditions the developing eggs need to incubate successfully before hatching, a reproductive strategy shared broadly across many desert-dwelling lizard species.
Where does the twin-spotted spiny lizard live?
This species is native to desert grassland and adjacent scrub habitat across parts of the southwestern United States and northern Mexico, favouring open ground with enough loose soil and low vegetation to support its basking and foraging habits.