I went back to the site where a friend found the brittle star mass mortality assemblage I posted here on the 16th of May. I wanted to look for one of my own and was just about to give up when I spotted this rock with more than just arms this time.
This central disc is 7mm across and some of the arms are still attached. This is from the Duck Creek Formation in Cooke County Texas which is in the Washita Group, Albian Stage of the Lower Cretaceous. Is this enough detail to put a name on the label for this thing? I'll settle for a family if no one knows the genus or species.