Any Texas Echinoid folks here? I believe I found this at Lake Benbrook or possibly Scorpion Hill. I looked in the TX Field Guide but do not see any matches, especially the tubercles. It was encrusted with a cemented sandy matrix which softened up after a few years in the garden, I cleaned it off the other day.
@theodore-gray Frankly, they all look alike to me. However, I suggest you obtain a copy of Collector’s Guide to Texas Cretaceous Echinoids by William W Morgan, Schiffer publishing, 2016. He’s got all of them covered.