DESERT SUN (Palm Springs, California) 09 November 13 Lizards always on the defense (James Cornett)
I nearly crushed it beneath my boot.
A little over a week ago, I was hiking down the Bogert Trail when something very tiny scampered out from underneath my boot — just in time to avoid being squashed. It was so tiny the entire animal could have easily hidden beneath a quarter.
It stopped on the side of the trail and gazed at me as though it had never seen a human before. Perhaps it had not. The creature was a recently hatched Desert Horned Lizard (Phrynosoma platyrhinos). The relatively large spines that are large and sharp on the head of an adult horned lizard were mere nubbins on the little guy in front of me.
Its lack of fully developed armament made it seem particularly vulnerable to predators, functionally speaking an “hors d’oeuvre” for a snake, roadrunner or fox. Alas, the months ahead will bring not only predators but also drought, extreme heat and a few nights of near-freezing temperatures in winter. The truth is that the tiny reptile will be lucky to reach adulthood.
Horned lizards are a fascinating group of reptiles. If I were to describe a creature covered with spines, had a torso as flat as a pancake, squirted blood from its eyes, ate nothing but ants and couldn’t outrun a tortoise, most people would snicker in disbelief. Horned lizards, however, are just such animals.
Horned lizards are a collection of eight southwestern reptile species that are often referred to by children as “horny toads” because of their chunky bodies. Toads are, of course, amphibians not reptiles and are not related to horned lizards in any way. Horned lizards are covered with coarse scales and lay their eggs on dry land. Amphibians have no scales and must lay their eggs in water or at least very moist surroundings.
Eight species live in the American deserts. Three of these are found in the Coachella Valley: the Desert Horned Lizard, Flat-tailed Horned Lizard (Phrynosoma mcallii) and Coast Horned Lizard (Phrynosoma coronatum). They are seldom observed because of their subtle colors and patterns that perfectly match local substrates. By lying motionless, horned lizards virtually disappear and usually avoid detection by predators
In addition to camouflage, adult horned lizards have a second defense mechanism consisting of dagger-like spines on the head and body. So effective is this armament that no snake species regularly preys upon horned lizards. In captive trials, lizard-eating snakes consistently refuse to devour adult horned lizards, preferring not to have their internal anatomy punctured by spines.
Horned lizards have evolved another defense mechanism. When handled roughly, they expel blood out the corner of each eye. This is done with amazing force and tiny droplets of blood may be ejected up to six feet, both splattering and startling an enemy. There is evidence the ejected blood may cause pain and stomach cramps if swallowed.
The wide, flattened body prevents horned lizards from running fast. They are thus most abundant on open flatlands where hiding places are scarce and any small, slow-moving reptile is exceptionally vulnerable to predators. This is probably why horned lizards have evolved more defensive adaptations than other lizard groups.
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