MYLIOBATIDAE Bonaparte, 1835

Adnet, Sylvain, Marivaux, Laurent, Cappetta, Henri, Charruault, Anne-Lise, Essid, El Mabrouk, Jiquel, Suzanne, Ammar, Hayet Khayati, Marandat, Bernard, Marzougui, Wissem, Merzeraud, Gilles, Temani, Rim, Vianey-Liaud, Monique & Tabuce, Rodolphe, 2020, Diversity and renewal of tropical elasmobranchs around the Middle Eocene Climatic Optimum (MECO) in North Africa: New data from the lagoonal deposits of Djebel el Kébar, Central Tunisia, Palaeontologia Electronica (a 38) 23 (2), pp. 1-62 : 40

MYLIOBATIDAE Bonaparte, 1835 and RHINOPTERIDAE Jordan and Evermann, 1896

Figure 13 F-K

Many fragmentary myliobatid and rhinopterid teeth were collected in KEB-1 deposits. Often reduced to broken elongated teeth or hexagonal lateral teeth that constitute the usual tooth plate of these cruching taxa with pavement-like teeth, they mainly belong to the genera “ Myliobatis ” (abundant, large size; Figure 13 H-J) Rhinoptera (abundant, small to medium size; Figure 13 F-G) and “ Aetobatus ” (extremely rare but distinguishable by its lingually extended root; Figure 13K ). Accurate species identification is hard from isolated teeth, especially when they are damaged. Hovestadt and Hovestadt-Euler (2013) largely refigured numerous fossils myliobatids and some rhinopterids, including those usually recorded during the Paleogene. The main result of such a comprehensive comparative study is that the absence of complete or partial pavement-like jaw does not allow for a confident determination, explaining why we left them in open nomenclature.

Figures

FIGURE 13. A-E. Coupatezia cristata nov. sp. A. antero-lateral tooth KEB 1-205, HOLOTYPE, A1.occlusal view, A2. Profile, A3. Labial view; B. Anterior tooth KEB 1-206, B1. Lingual view, B2. Basal view, C. lateral tooth KEB 1-207, C1. Occlusal view, C2. Magnificence of C1, C3. Lingual view; D. lateral tooth KEB 1-208, D1. Occlusal view, D2. Magnificence of D1, D3. Lingual view; E. lateral tooth KEB 1-209, E1. Occlusal view, E2., lingual view, E3. Basal view. F-G. Rhinoptera sp. F. medium tooth KEB 1-210, lingual view, G. medium tooth KEB 1-211, labial view; H-J. Myliobatis sp., H. lateral tooth KEB 1-212, lingual view, I. medio-lateral tooth KEB 1-213, lingual view, J lateral tooth KEB 1-214, lingual view; K. Aetobatus sp. KEB 1-215, ligual view, L-M. Garabatis sp., L. KEB 1-216, occlusal view, M. KEB 1-217, L1. occlusal view, L2. Magnificence of central part, L3. Magnificence of marginal part of crown.