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Cantioscyllium is an extinct nurse shark erected by Woodward (1889) based on a partial skeleton from the Late Cretaceous of England. The teeth are small, following the general nurse shark-design: a low, robust, lingually inclined crown, in which the lower labial margin extends well beyond the V-shaped roots. The shoulders lack the strongly developed cusplets present in other nurse sharks, replaced by one to three low and rounded projections. The labial crown face bears enameloid wrinkles which may be weak (Fig ) to strong (Fig ). The root bears a central pore and a lateral foramen on the external face of each lobe. The dentition is clutching in design with gradational monognathic heterodonty. Anterior teeth are mesio-distally compressed with more upright crowns when contrasted with the expanded lateral/posterio-lateral positions.
Cappetta (1973a) reported Cantioscyllium decipiens from the Turonian, South Dakota.
In his unpublished thesis, Meyer (1974) recognized two forms of Cantioscyllium teeth from the Late Cretaceous of the NA Gulf Coast which he termed C. decipiens (Cenomanian-Coniacian) and C. "saginatus" (Santonian-Maastrichtian).
Cappetta (1987: 78-79) included C. decipiens in the Cenomanian-Turonian of Western Europe and the North American inland sea.
Williamson et al. (1989) included C. decipiens from the Santonian of New Mexico.
Manning & Dockery (1992: 26-27) reported these teeth from the Late Campanian of the Mississippi Embayment and Manning (2006) noted their presence in Late Santonian horizons as well.
Welton & Farish (1993:82) included it in the Cenomanian-Coniacian of Texas,
Hamm & Cicimurri (2011:113) in the Atco Formation (Early Coniacian) of Texas
and Kent (1994: 32-34) from the Maastrichtian of Maryland.
Case & Cappetta (1997: 136) erected C. meyeri for Cantioscyllium teeth from the Maastrichtian of Texas. They noted that compared with Herman (1977, plate VI), these teeth were:
smaller
lateral teeth less laterally expanded
marginal cusplets less numerous, and
reduced number of labial folds
In North Carolina. Cantioscyllium teeth are represented but uncommon in the Tar Heel Fm (Campanian) and possibly Peedee Fm (Maastrichtian).
They are included below as C. decipiens although they have elements of the "C. meyeri" description;
it is difficult to accept latter's morphology as anything more than a subtle chrono/morpho-species at this time.
Selected References
Bourdon, J., Wright, K., Lucas, S.G., Spielmann, J.A. and Pence, R., 2011. Selachians from the Upper Cretaceous (Santonian) Hosta Tongue of the Point Lookout Sandstone, central New Mexico. New Mex. Mus. Nat. His. and Sc., Bulletin 52; 54pp.
Cappetta, H., 1973a. Selachians of the Carlile Shale (Turonian) of South Dakota: Journal of Paleontology, v. 47, p. 504-514.
Cappetta, H., 1987. Chondrichthyes II. Mesozoic and Cenozoic Elasmobranchii. In: Handbook of Paleoichthyologie, vol. 3b, Gustav Fischer Verleg, Stuttgart, 193 pp.
Case, G. and Cappetta, H.. 1997. A new selachian fauna from the late Maastrichtian of Texas. Münchener Geowissenschaften Abhandungen 34:131-189.
Hamm, S.A. and D.J. Cicimurri, 2011. Early Coniacian (Late Cretaceous) selachian fauna from the basal Atco Formation, Lower Austin Group, north central Texas; Paludicola [Rochester Institute of Vertebrate Paleontology] 8(3):107-127.
Herman, J., 1977. Les Sélaciens des terrains néocrétacés & paléocènes de Belgique & des contrées limitrophes Eléments d'une biostratigraphie intercontinentale. Mem. Expl, Cartes Géo. & Min. de la Belg, Mém, no. 15, 450 pp, 25 figs, 21 pls.
Kent, B., 1994. Fossil Sharks of the Chesapeake Region. Egan Rees & Boyer, Maryland. 146 pp
Manning, E. and Dockery III, D, 1992. A guide to the Frankstown vertebrate fossil locality (Upper Cretaceous), Prentiss County, Mississippi. Mississippi Dept. of Env. Qual., Office of Geology, Circular 4, 43 p., 12 pls.
Manning, E., 2006. Late Campanian vertebrate fauna of the Frankstown site, Prentiss County, Mississippi; systematics, paleoecology, taphonomy, sequence stratigraphy. Unpub. PhD dissertation, Tulane Univ., New Orleans, xvii+419 p., 16 pls.
Meyer, R., 1974. Late Cretaceous elasmobranchs from the Mississippi and East Texas embayments of the Gulf Coastal Plain [Ph.D. dissertation]: Dallas, Southern Methodist University, 419 p.
Welton, B. and Farish, R., 1993. The Collector's Guide to Fossil Sharks and Rays from the Cretaceous of Texas. Before Time, Texas. 204 pp.
Williamson, T.E., Lucas, S.G. and Pence, R., 1989. Selachians from the Hosta Tongue of the Point Lookout Sandstone (Upper Cretaceous, Santonian), central New Mexico: New Mexico Geological Society, Guidebook 40, p. 239-245.
Woodward, A., 1889. Catalogue of the fossil fishes in the British Museum, Part 1. London, 474pp.
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