Upper Permian crinoids from Djebel Tebaga, Tunisia

A small crinoid fauna of Guadalupian age is described from the Djebel Tebaga area of southern Tunisia. The crinoids are associated with sponge-rich bioherms and are judged to have lived in shallow but gently agitated waters. Unusual adaptations include an unusual stem type, ascribed to Tetrabrachiocrinus, in which the normal columnals are surrounded by an outer layer of small plates here called plinths. The fauna includes two camerate crinoids, ?Paragaricocrinus yakovlevi n. sp., and an unusual new genus related to dichocrinids, Tunisiacrinus imitator n. sp., that is a homeomorph of the inadunate Tetrabrachiocrinus, and is assigned here to a new family. Two new mespilocrinid flexible crinoids are present, Trinalicrinus tunisiensis n. gen., n. sp., which has affinities with Timor Permian crinoids, and Strobocrinus brachiatus n. gen., n. sp., that is evolutionarily advanced in lacking an anal plate in the posterior interray. The fauna shows relationship to Permian crinoids described from Sicily and Timor, but may be younger than these other Permian faunas.