Head to head
Granite Spiny Lizard vs Yarrow's Spiny Lizard
A granite spiny lizard and Yarrow's spiny lizard both belong to the same genus of rough-scaled, sun-loving lizards, yet they have adapted to noticeably different elevations and reproductive strategies within the southwestern mountains.
| Granite Spiny Lizard | Yarrow's Spiny Lizard | |
|---|---|---|
| Scientific name | Sceloporus orcutti | Sceloporus jarrovii |
| Reproduction | Egg-laying | Live-bearing |
| Elevation | Lower desert and mountain terrain | Notably higher mountain elevations |
| Signature trait | Iridescent blue-purple male colouration | Dark collar marking, cold-adapted birth |
| Habitat | Granite boulder outcrops | Oak-pine sky-island woodland |
| Range | Southern CA and northern Baja California | SE Arizona, NM, adjacent Mexico |
| Body build | Large, robust, heavily scaled | Stocky, heavily scaled |
| Conservation status | Least Concern | Least Concern |
Granite Spiny Lizard vs Yarrow's Spiny Lizard: common questions
Why does Yarrow's spiny lizard give birth to live young while the granite spiny lizard lays eggs?
Yarrow's spiny lizard occupies notably higher, colder mountain elevations than the granite spiny lizard, and live birth lets a mother regulate the developing young's temperature internally rather than leaving eggs exposed to cool mountain soil, an adaptation the lower-elevation granite spiny lizard does not need.
How can you tell these two spiny lizards apart?
An adult male granite spiny lizard displays a striking iridescent blue-purple sheen not seen in Yarrow's spiny lizard, which instead shows a bold dark collar marking across the shoulder area, along with generally occupying higher-elevation oak-pine woodland rather than granite boulder outcrops.
Do these two lizards live in the same part of the Southwest?
Not typically — the granite spiny lizard is found across southern California and northern Baja California, while Yarrow's spiny lizard occupies isolated sky-island mountain ranges of southeastern Arizona, New Mexico, and adjacent Mexico, meaning the two generally occupy separate regions.