Reptiles
Short-Horned Lizard
Phrynosoma hernandesi · also called greater short-horned lizard
High on a cool mountain slope, far above where most desert-dwelling horned lizards could ever survive, a short-horned lizard basks on open rock, carrying developing young inside its own body rather than risking eggs in ground too cold to properly incubate them.
Overview
The short-horned lizard, Phrynosoma hernandesi, is a cold-tolerant horned lizard native to mountain and grassland habitat across a broad stretch of western North America. Its live-bearing reproduction and unusually wide-ranging tolerance for cold set it apart from the more heat-dependent, egg-laying horned lizard species found further south.
A horned lizard built for the cold
While most of its relatives are confined to warm desert lowlands, the short-horned lizard has pushed both north and upward into genuinely cold terrain, trading the typical horned lizard strategy of egg-laying for live birth to make that colder range actually survivable.
Status
Least Concern — widespread across suitable mountain and grassland habitat throughout western North America.
Short-Horned Lizard: common questions
Why does the short-horned lizard give live birth instead of laying eggs?
The short-horned lizard gives live birth rather than laying eggs, an adaptation well suited to the cooler climates and shorter growing seasons found across much of its range, since carrying developing young inside a warmer body rather than leaving eggs exposed to cold ground improves the chances of successful development.
How far north does the short-horned lizard live compared to other horned lizards?
The short-horned lizard tolerates colder conditions and occupies a range extending further north and to higher elevation than any other horned lizard species, allowing it to survive in mountain and grassland habitat that would be too cold for its more heat-dependent desert relatives.
Can the short-horned lizard really squirt blood from its eyes?
Yes, like several other horned lizard species, the short-horned lizard can squirt a thin stream of blood from the corners of its eyes as a startling last-resort defense against a persistent predator, a dramatic response reserved for genuinely serious threats rather than routine encounters.
Where does the short-horned lizard live?
The short-horned lizard is native to mountain slopes and grassland habitat across a broad range of western North America, occupying cooler and higher-elevation terrain than most other horned lizard species are able to tolerate.