Reptiles
Crevice Spiny Lizard
Sceloporus poinsettii · also called crevice spiny lizards
A crevice spiny lizard basks openly on a sun-warmed boulder, but the moment a shadow passes overhead it vanishes into a narrow crack in the rock, its flattened body wedged so tightly into the same favoured crevice it has returned to many times before that no predator could hope to follow.
Overview
The crevice spiny lizard, Sceloporus poinsettii, is a large, robust lizard native to rocky outcrops, canyon walls, and boulder fields across the southwestern United States and northern Mexico. Its near-total dependence on rock crevices, flattened body built for squeezing into narrow cracks, and strong fidelity to a specific favoured retreat make it one of the more habitat-specialised spiny lizards in North America.
A lizard that never strays far from its escape hatch
Rather than relying on speed across open ground, the crevice spiny lizard builds its entire survival strategy around never being far from a crack it can vanish into instantly, a specialisation that shapes nearly every aspect of its behaviour.
Status
Least Concern — widespread and stable across suitable rocky habitat throughout the southwestern United States and northern Mexico.
Crevice Spiny Lizard: common questions
Why does the crevice spiny lizard vanish so quickly when approached?
This species spends the great majority of its life on or within rock crevices and retreats into a chosen crack at the very first sign of danger, using its somewhat flattened body to wedge tightly into narrow spaces predators cannot easily follow into, which is why an individual basking openly on a rock face can seem to disappear entirely within an instant.
Does the crevice spiny lizard always use the same hiding spot?
Often, yes, this species shows strong site fidelity to a particular favoured rock crevice, returning to and defending the same specific retreat over an extended period rather than treating every crack in the same rock face as equally suitable.
How big does a crevice spiny lizard get?
This species is one of the larger members of its genus, with a stocky, robust build well suited to defending a favoured crevice against rival lizards, larger overall than several of its more slender spiny lizard relatives.
Where does the crevice spiny lizard live?
This species is native to rocky outcrops, canyon walls, and boulder fields across the southwestern United States and northern Mexico, generally staying close enough to suitable crevice habitat to retreat into cover within moments of any disturbance.