Reptiles
Texas Horned Lizard
Phrynosoma cornutum · also called Texas horned lizard, horned toad, horny toad
The Texas horned lizard — the “horny toad” of Southwestern childhoods — is a flat, spiky, slow-moving desert lizard that lives almost entirely on ants. And when a coyote or a dog finally catches one, it has a last card to play: it squirts a jet of its own foul-tasting blood straight into the predator’s mouth.
Overview
Texas horned lizards live in arid and semi-arid shrubland, grassland, and open desert with loose sandy or loamy soil across the south-central US and northern Mexico. They are diurnal, bask to warm up, and bury themselves in the soil at night and through the midday heat, wriggling under with sideways body movements. They are ambush feeders, sitting near an ant trail and picking off harvester ants one by one — ants can be 70% of the diet.
A layered defence
- Camouflage — a still horned lizard, mottled to match the ground, is very hard to see.
- Look unswallowable — it inflates its body and tilts its head horns toward the threat.
- Blood-squirting — as a last resort against a canid, it ruptures sinuses at the corners of its eyes and fires a stream of blood up to 1.5 metres, aimed at the attacker’s face. The blood carries foul-tasting compounds (apparently from the harvester ants’ venom), and a dog or fox that gets a mouthful drops the lizard, drooling.
Not a toad
Despite “horned toad” and “horny toad,” it is a true lizard; the names come from its squat, round, toad-like body. The genus name Phrynosoma means “toad-body.”
Status
The Texas horned lizard is globally Least Concern but declining and locally extinct across much of Texas and neighbouring states. The core cause is the collapse of native harvester ants — wiped out by invasive fire ants and broad-spectrum insecticides — compounded by habitat loss, road kill, and historic pet-trade collection. It is now protected across much of its US range, with ant restoration and captive breeding underway.
Texas Horned Lizard: common questions
Do horned lizards really shoot blood from their eyes?
Yes, though not all species and not on demand. The Texas horned lizard and several relatives can, as a last-ditch defence, sharply increase the blood pressure in the head and rupture thin-walled sinuses at the corners of the eyes, sending a fine stream of blood as far as a metre and a half, usually aimed at the face of an attacker. It is specifically effective against canids — foxes, coyotes, and domestic dogs — because the blood contains chemicals, apparently derived from the venom of the harvester ants the lizard eats, that taste foul to them; a dog that gets a mouthful will typically drop the lizard and shake its head and drool. It has little effect on birds or snakes, so the lizard uses other defences against those.
Is it a lizard or a toad?
A lizard. The traditional names "horned toad" and "horny toad" come from its squat, rounded, wide-bodied shape, which is toad-like, but it is a true lizard with scales, claws, external ears, and a tail, in the family Phrynosomatidae (spiny and sand lizards). The genus name Phrynosoma even means "toad-body." It moves slowly, is active by day, basks, and buries itself in loose soil at night and to escape heat, shuffling under the surface with sideways body movements until only its head shows.
Why is the Texas horned lizard disappearing?
Mainly because its food is disappearing. The lizard is a harvester-ant specialist, and native harvester ants have been devastated across the American Southwest by two things — the spread of the invasive red imported fire ant, which outcompetes and displaces them, and the widespread use of broad-spectrum insecticides on farmland and for fire-ant control, which kills the native ants too. On top of that, the lizard has lost habitat to farming, urban sprawl, and overgrazing, it is frequently killed on roads, and it was heavily collected for the pet trade in the mid-20th century (it almost never survives in captivity). It has vanished from about half of its former Texas range.
Can you keep one as a pet?
You should not, and in most of its range it is illegal. Texas horned lizards are notoriously difficult to keep alive because their diet is so specialised — they need a constant supply of live harvester ants, which are hard to source and maintain, and they do poorly on substitutes. Historically, huge numbers were sold as souvenirs and pets and nearly all died within weeks or months. The species is now protected in Texas, Oklahoma, and elsewhere, collection is banned, and conservation efforts focus on restoring native ant populations and habitat and on captive-breeding-and-release programmes run by zoos.