A new bourgueticrinid (Crinoidea) from the Castle Hayne Formation (Eocene) of southeastern North Carolina, USA

Abstract

Cenozoic fossil stalked crinoids are poorly known. Based on a large, new collection of disarticulated columnals and cups, a new gracile bourgueticrinid, Democrinus simmsi species nov., is described from the Eocene Castle Hayne Formation as exposed at the Martin Marietta Quarry, New Hanover County, southeastern North Carolina (USA). The smooth, conical cup of D. simmsi commonly is widest at the oral surface, moderately flared orally in small (juvenile?) specimens, but tends to be subcylindrical in larger examples. The basals are at least 1.5 times the height of radials. Some columnals of mesistele and dististele have distinctly warty latera. This is the first nominal bourgueticrinid from the Paleogene of North America, despite their moderate diversity locally in the Paleogene of Eurasia. The small size of cups and disarticulated columnals of gracile bourgueticrinids are almost certainly a factor in our poor knowledge of their fossil record.