Appearance
Texas horned lizards get their name from the spiny structures that cover their entire body, and especially the two that crown their head. The largest of the 21 horned lizard species, males can reach up to 5 inches from nose to tail. The coloration of a Texas horned lizard can vary based on the environment they live in. In deserts they tend to be more yellow or tan in color, while in prairies they will lean red or brown to match soil color. All Texas horned lizards have dark lines from the sides of their eyes to the tips of their crown, as well as a solid white line that traces their spine.
Adaptations
Texas horned lizards are actually found in several states, and have adapted to live in a variety of habitats, from the Chihuahua Desert to the piney woods region of east Texas and into Louisiana. Regardless of habitat, they are very commonly found near harvester ant colonies, a species which makes up nearly all of their diet. Texas horned lizards contain a special blood plasma factor that makes them immune to harvester ant venom. Additionally, they produce excess mucus to ensnare and incapacitate the ants once they're swallowed.
Perhaps the most famous of their adaptations, Texas horned lizards are able to squirt a stream of blood from the corners of their eyes by manually increasing their blood pressure. This blood stream can travel up to 5 feet, and is typically used in self-defense. A chemical produced by the lizard mixes with the blood and produces a foul taste that often deters major predators like wolves and coyotes.
Conservation
The Texas horned lizard has seen a rapid decline in recent years, mostly due to habitat loss and the encroachment of invasive species. Among these invasive species, the red imported fire ant has been a particular problem for the lizard population. They overtake colonies of native harvester ants, thereby destroying the main food source of Texas horned lizards. The lizards lack any defense against fire ant venom, and hatchlings that find themselves attacked by the ants are often killed.
Teams such as the Center for Conservation Research at the San Antonio Zoo Horned Lizard Reintroduction Project have spearheaded efforts to breed and release lizards back into their historic range. This is done with the cooperation of private land owners who agree to allow lizards to be released onto their property. Not only does this provide a home for displaced lizards, but it helps to restore native biodiversity across Texas.
Where are they?
Our Texas horned lizards live in the Intensive Management Area. The building can be seen on a Behind-The-Scenes Tour.
VIEWING TIPS
Our lizards are adjusting to their new surroundings, and their building cannot currently be entered by guests.
Quick Facts
Scientific Name | Phrynosoma cornutum |
Species Survival Plan | No |
Habitat | Arid and semi-arid spaces in the south-central United States. |
Food | Harvester ants supplemented by other insects like beetles and grasshoppers. |
Originally Native To | South-central U.S. |
Characteristics | 3.7 to 5 inches in length, covered with spiny horns. Can range from yellow-tan to reddish-brown with a solid white line along the back. |
Lifespan | Unknown in wild, |
Social Behavior | Solitary except during mating season. |