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Palaeogaleus is an extinct genus of triakid sharks, which is thought to have had a dentition similar to that of Galeorhinus and Triakis (dignathic heterodonty) and teeth including characteristics of each. Palaeogaleus teeth are small (<4mm) have a distally directed cusp flanked by 1 or more lateral cusplets. Unlike the distal cusplet(s), which tend to remain well individualized, the mesial ones often amalgamate leaving only a crenulated shoulder. Strong enameloid ridges (folds, wrinkles) often run longitudinally on the labial face of the crown and the lingual face of the cusplets/shoulders. Labially, the crown overhangs the root with a prominent bulge or bourrelet. The roots are wide, flat and high, have a deep nutrient groove, central pore and numerous margino-lingual foramina. They can be best differentiated from other triakids by the thickness of the cusp, height of the roots and strength (and length) of the folds.
Species ascribed to this genus include (chronologically):
P. dahmanii NOUBHANI & CAPPETTA (1999) Maastrichtian Morocco & Egypt
P. faujasi ARAMBOURG 1952 Upr Cretaceous Western Europe
P. havreensis HERMAN 1977 Upr Cretaceous Belgium
P. brivesi (ARAMBOURG 1952) Danian Morocco & Europe
P. prior (ARAMBOURG 1952) Danian Morocco
P. vincenti DAIMERIES 1888 Palaeocene Western Europe, England, Greenland, No America
P. larachei NOUBHANI & CAPPETTA (1999) Thanetian Morocco & Europe
P. sublaevis NOUBHANI & CAPPETTA (1999) Ypresian Morocco.
In North America, Welton & Farish (1993: 128) included Palaeogaleus sp as common in the Campanian - Maastrichtian of Texas. Ward & Weist (1990) included P. vincenti in the faunas of the Brightseat and Aquia (Piscataway Mbr) Formations of Maryland, and Kent (1999: 24) placed it in the lower Nanjemoy (Potapaco Mbr - Ypresian) of Virginia. Case & Cappetta (1997: 143) erected P. navarroensis for the Kemp Clay (Maastrichtian, Texas) teeth reported by Welton & Farish. The included North Carolina specimen (Fig. ) compares much better with P. faujasi (Fig. ) than the other two species with a published NA fossil record.
Selected References
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.
Herman, J., 1977. Les sélaciens des terrains néocrétacés et paléocènes de Belgique et des contrées limitrophes. Eléments d'une biostratigraphie intercontinentale. Mémoires pour servir à l'explication des Cartes géologiques et minières de la Belgique, 1975 (paru 1977), 15: 401 pp.
Kent, B. 1999. Sharks from the Fisher/Sullivan Site. In: Weems, R. & Grimsley, G., Early Eocene Vertebrates and Plants from the Fisher/Sullivan Site (Nanjemoy Formation) Stafford County, Virginia. Virginia Division of Mineral Resources, Pub 152: 11-37.
Noubhani, A and Cappetta, H., 1997. Les Orectolobiformes, Carcharhiniformes et Myliobatiformes des Bassins à phosphate du Moroc (Maastrichtien-Lutétien basal)., PalaeoIchthyologica 8, München. 327 pp
Ward, D. and Wiest, R., 1990. A checklist of Paleocene and Eocene sharks and rays (Chondrichthyes) from the Pamunkey Group, Maryland and Virginia, USA. Tertiary Res., 12(2) p 81-88.
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.
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