Blastoids from the late Osagean Fort Payne Formation (Kentucky and Tennessee)

Abstract

A largely new, Early Mississippian blastoid fauna is described from the Fort Payne Formation of south-central Kentucky and north-central Tennessee. The fauna consists of nine species assigned to eight genera, including four new genera and six new species. The fauna includes Hadroblastus breimeri n. sp., Granatocrinus granulatus (Roemer), Dentiblastus macurdai n. sp., Deliablastus cumberlandensis n. gen. and sp., D. tribulosus n. gen. and sp., Xyeleblastus magnificus n. gen. and sp., Perittoblastus liratus n. gen. and sp., Euryoblastus veryi (Rowley) n. gen., and an unidentifiable basal circlet that may represent a phaenoschismatidid. All spiraculates belong to the Granatocrinidae.The Fort Payne Formation has the most diverse blastoid fauna known between the middle Osagean blastoid extinction and the Permian. Diversification immediately after the middle Osagean extinction is recorded in the Fort Payne and is largely a diversification of the Granatocrinidae.Orbitremites grandis Rowley (1902) is an internal mold from the Fort Payne Formation. This specimen cannot be identified and is designated as a nomen dubium.