Original paper
Jurassic and Cretaceous crinoids (Crinoidea, Echinodermata) from the southern Tethys margin (northern and eastern Africa, and southern Asia)
Salamon, Mariusz A.; Benyoucef, Madani; Jain, Sreepat; Benzaggagh, Mohamed; Płachno, Bartosz J.; Abdelhamid, Marouf A. M.; Ahmad, Fayez; Azar, Dany; Bouchemla, Imad; Brachaniec, Tomasz; El Ouali, Mohamed; El Qot, Gamal; Ferré, Bruno; Gorzelak, Przemysław; Krajewski, Marcin; Klompmaker, Adiël A.; Mekki, Fayçal; Paszcza, Karolina; Poatskievick-Pierezan, Bruna; Slami, Rafika; Hoşgör, İzzet
Palaeontographica Abteilung A Band 328 Lieferung 1-6 (2024), p. 1 - 99
459 references
published: Aug 23, 2024
published online: Jul 22, 2024
manuscript accepted: May 16, 2024
manuscript received: Mar 9, 2024
Abstract
This article focuses on Jurassic and Cretaceous crinoids found in the central part of the southern Tethys shelf. The specimens presented herein come from African and Asian countries (from west to east: Morocco, Algeria, Egypt, Ethiopia, Kenya, Lebanon, Jordan, Madagascar, and India). These records are based on the study of over 30,000 crinoid remains, including cups, thecae, centrodorsals, radials, basals, brachials, columnals, pluricolumnals, cirri, and cirrals. Among the stalked crinoids, 36 isocrinid, 7 cyrtocrinid, 8 comatulid, 1 incertae sedis, and several millericrinid taxa were recorded from northern and eastern Africa, the Middle East, and India. The free-swimming roveacrinids are represented by 39 taxa. We note that the number of millericrinid taxa has been overestimated and, hence, this group requires a thorough reevaluation. All crinoids were classified as stalked isocrinids, Isocrinida (Seirocrinus subangularis Balanocrinus subteres B. pentagonalis B. gillieroni B. cf. ticinensis Percevalicrinus sp., P. aldingeri, Isocrininae indet., Isocrinus legeri I. nicoleti I. dumortieri I.? lissajouxi I.? granosus, Chariocrinus andreae C. basaltiformis Pentacrinites sp.), cyrtocrinids, Cyrtocrinida (Cyrtocrinina indet., Eugeniacrinites sp., Apsidocrinus sp., Phyllocrinus belbekensis Ticinocrinus moroccoensis Hemibrachiocrinus sp.), comatulids, Comatulida (Bourgueticrinus sp., Ausichicrinites zelenskyyi Semiometra algeriana n. sp., Comatulina infracretaceus Copernicrinus zamorae, Comaturella pinnulata), and millericrinids, Millericrinida (Millericrinida fam. et gen. indet, Millericrinus annulatus M. charpyi M. horridus, and M. munsterianus). The remains of free-swimming roveacrinids (Roveacrinida) are also documented and represented by isolated thecae, radials, basals, spines, and brachials. Numerous remains of roveacrinids are visible in thin sections; these will be published elsewhere. Additionally, a critical systematic review of the crinoids mentioned and illustrated in the literature is also provided. The millericrinid remains from the Campanian of Alabama, southeastern USA, were used for comparative purposes and represent the youngest occurrence of the order Millericrinida in the world thus far. The abundance of crinoid genera between the northern and southern Tethys parts is shown to be significant. However, the number of crinoids in Africa, the Middle East, and India remains underestimated. Possible reasons for this underestimation are provided.
Keywords
Crinoidea • Mesozoic • southern Tethys margin • Maghreb • Africa • Middle East • India