This is a spiny softshell turtle (A. spinifera) found in many waterways of Cook County, preferring slow-moving waters, but it is often seen in lakes with sandy banks and bottoms. It is called a softshell because of its distinct leathery, flexible carapace in place of the normally keratinized shell of other aquatic turtles, and the spiny descriptor is due to the tubercles protruding from the front of its carapace, which distinguishes it from other softshell species like the smooth and Florida softshell.
These slippery pancakes of a turtle are a favorite of Cook County, not only for their alien-like appearance but also for the challenge of sampling, as they are surprisingly fast and will zip off once set down on solid ground. Hematological samples are often plagued by rapid clot development.
