Horned Lizards

The Essays of Frances Williams, October 1964

Published May 13th 2017 in Wildlife, reptiles, horned lizard, Frances Williams

A round, diminutive, spiny animal, no longer than a 50-cent piece, scurried hurriedly through the grass at 203 North D. Its color was dark brown, with blotches of black edged by deep green. It merged into the shadows of leaves and grass, a perfect example of nature's camouflage. It was a Texas Horned Lizard, known affectionately to southwestern children as a "horny toad." If it had lived in an open, sandy area, rather than-the well-shaded haven of 203 North D, it would have been pale yellowish-brown, with dark brown blotches edged by white or pale yellow.

Food of horned lizards includes many garden enemies: ants, beetles, caterpillars, and sowbugs. The gardener who finds several of these lizards have made their abode in his yard should be cautious in using poisons. Horned lizards are killed by small quantities of insecticides.

Three species of horned lizards live in west Texas. Texas Horned Lizard, Round-tailed Horned Lizard, and Short-horned Lizard. They are easily distinguished. Texas has two rows of spines along his sides, Short-horned has a single row, and Round-tailed has none. Shorthorned has horns less than half as long as those of the Texas species. Texas Horned Lizards are the largest, growing to 4 inches 2-3/4 inches.

All three species adapt their coloration to the area in which they live. MIDNATS have found, in Trans-Pecos Texas, Short-horned Lizards that were reddish, matching the reddish sandstones or igneous rocks of their habitat. Ditmars (REPTILES OF NORTH AMERICA) described Short-horned Lizards which were perfect Imitations of lichen-covered rocks. He also told of individuals that lived in a black lava belt, and were satiny black with rich yellow markings.

The little "horny toad" at 203 North D was a young one, hatched this summer. In the Texas Horned Lizard, mating occurs in April, and May. Eggs are laid in May or June. The female digs, usually in late afternoon, a straight slanting tunnel about 6 inches long. She enlarges the end to serve as an egg chamber. She lays as many as 27 eggs, depositing them in three horizontal layers, separating the layers by firmly packed sand. The eggs are cream-colored, very tough and leathery. They hatch in about 40 days.

Round-tailed Horned Lizards also lay eggs, but reproduction, is quite different in Short-horned Lizards. The females of this species retain the eggs within their bodies until the young are well developed. The eggs remain membranous, and the young are able to break out as soon as the eggs are deposited. These tiny microcosms of life can immediately run about or burrow into the sand. It is interesting to speculate what could have caused these two varying adaptations in species of the same genus.

Photos courtesy of Michael W. Nickell-Sibley Nature Center.