After inspecting the eyespot of a flailing Caligo butterfly, I looked aside to find this black ctenosaur (Ctenosaura similis) eyeing me from a nearby rock. The grasses between us were thick and swayed wildly in the wind, so obstructive that I was able to veer close to sneak a detailed shot. These iguanids are robust and impressive lizards, among the fastest running reptiles on the planet. Males reach over four feet in length and have a beautiful spiny crest with black, white, and blue hues. It’s incredible just how blue (and green) ctenosaurs can be, especially as juveniles. When I first observed young ctenosaurs at Palo Verde several years ago it was hard to believe they were in fact the same species.