greater earless lizard

Here’s a lizard.

Newbie greater earless lizard (Cophosaurus texanus), on a red sandtone perch, at V-Bar-V Heritage Site in Yavapai County, Arizona.

This fellow was tiny, only about two inches (5 cm) long, excluding its beautiful banded tail. The bottom photo provides a good view of this lizard’s parietal or “third” eye, in the large central scale at the base of its head. Reptiles’ parietal eyes are photoreceptive, but don’t process light in the same manner as the rods and cones in the imaging eyes. Instead, the structure sends direct signals to the lizard’s pineal gland, which controls circadian rhythms and the chemistry of thermoregulation.

Greater earless lizard (Cophosaurus texanus) with a stubby, regenerated tail, at Tuzigoot National Monument, Yavapai County, Arizona.

Demi-godzilla.

This charming fellow didn’t present a lot of distinguishing marks for an ID, but based on its orange dewlap I think it is a greater earless lizard (Cophosaurus texanus). At Montezuma Castle National Monument, Yavapai County, Arizona.

Demi-godzilla.

This greater earless lizard was formerly a greater tailless lizard, but a stubby replacement tail is already in place.

For a scholarly look at the genetics behind the phenomenon of tail regeneration after

caudal autotomy

see Transcriptomic Analysis of Tail Regeneration in the Lizard Anolis carolinensis Reveals Activation of Conserved Vertebrate Developmental and Repair Mechanisms at PLOS-one. Fascinating stuff.

Greater earless lizard (Cophosaurus texanus), at Tuzigoot National Monument, Yavapai County, Arizona.