ammonites
Affinocrinus grandis Moore and Strimple 1973 (feather star)

Crinoidea - Dendrocrinida - Pirasocrinidae

Full reference: R. C. Moore and H. L. Strimple. 1973. Lower Pennsylvanian (Morrowan) crinoids from Arkansas, Oklahoma, and Texas. University of Kansas Paleontological Contributions, Echinodermata Article 60(12):1-84

Belongs to Affinocrinus according to R. C. Moore and H. L. Strimple 1973

Sister taxa: Affinocrinus normalis, Affinocrinus progressus

Type specimen: SUI 36240 (dorsal cup). Its type locality is Railroad cut near Union Mission (Loc. 9), which is in a Morrowan marine limestone/shale in the Bloyd Formation of Oklahoma.

Ecology: stationary intermediate-level epifaunal suspension feeder

Average measurements (in mm): dorsal cup 8.60 x 31.80