Members of this genus are relatively large (to 3.6 meters), little known, bottom dwelling, deepwater sharks reported from scattered locales in temperate and tropical waters. Compagno (2001) included two species in his FAO listing and noted they feed on small bony fishes, squid & shrimp. The grasping dentition lacks the crushing posterior teeth found in the genus Carcharias.
O. ferox (RISSO, 1810), the Smalltooth sand tiger has been reported from isolated locations (Eastern Atlantic, Pacific, Indian Oceans & Mediterranean), preferring somewhat deep waters of continental and insular shelves (15 - 400 m). This species' teeth bear 2- 3 pairs of lateral cusplets and the dentition includes 3 - 5 rows of intermediate teeth. O. noronhai (MAUL, 1955), the Bigeye sand tiger, prefers deeper waters (600-1000 m) of continental and insular slopes. It's known from isolated locales in Atlantic and Indian Oceans. In this species, the teeth have a single pair of lateral cusplets and there is a singular file of intermediate teeth.
As can be seen in the above tooth-set, the dentition of the extant species, O. ferox, is made up of slender sharp teeth with delicate and elongated cusplets. The upper anterior hollow contains three teeth (usually with two cusplets/side) and the medial-most (UA1) is stunted. The lower anterior hollow produces four file-positions, with the first (LA1) somewhat reduced in size. The intermediate bar of the upper jaw bears multiple files of reduced intermediate teeth. The first five or so upper lateral files are enlarged, similar to those of Carcharias. However, rather than transitioning into low-crowned crushing-type teeth as seen in Carcharias, the remaining files display gradient heterodonty. The first two lower laterals have cusps which are proportionately higher and medially-curved; the remaining files also display gradient heterodonty and lack the reduced tooth-group present in Carcharias.
To this author's knowledge, fossil Odontaspis or Odontaspis-like taxa have not been erected/identified on the basis of dentition-design but only tooth-design. Diagnostic tooth details included:
Narrow sharp primary cusps with multiple slender lateral cusplets,
Broadly splayed, U-shaped, narrow (when viewed labially) deep (when viewed laterally) root lobes,
Incomplete (basally) cutting-edge.
Cappetta (1987: 88) included four species known from the fossil record:
O. aculeatus (CAPPETTA & CASE, 1975) [Upper Campanian of New Jersey],
O. ferox [Lower Pliocene of Italy],
O. speyeri (DARTEVELLE & CASIER, 1943) [Palaeocene of Africa] and
O. winkleri LERICHE, 1905 [Lower - Middle Eocene of the Anglo-Franco-Belgian basin and Eocene of Maryland].
Cappetta & Case (1975: 16-18) erected two species from the Late Campanian of New Jersey. The first, erected as Hypotodus aculeatus, was subsequently moved to Odontaspis. Kent (1994:39) noted that O. aculeatus had been reported from the Marshalltown, Mount Laurel and Severn Formations of New Jersey, Delaware and/or Maryland. Case & Cappetta (1997: 151) included this taxon in the Maastrichtian of Texas. Becker et al (2004: 783) reported it from the Maastrichtian of South Dakota and Becker et al (2006: 703) Maast. Arkansas. This author has recovered a couple damaged specimens (Fig. & ) from the Late Cretaceous of North Carolina.
The second, erected as O. hardingi, was not included by Kent (1994) as present in the Chesapeake region. Teeth conforming to this description are somewhat uncommon in the Late Cretaceous of North Carolina. [In distinguishing these teeth and those of Cretaceous Carcharias of this region I follow the decision-tree on the accompanying webpage.]
Ward & Wiest (1990) reported O. winkleri from the Palaeocene [Danian &Thanetian] and Eocene [Ypresian] of Maryland and Virginia.
Case & Borodin (2000:21) erected O. carolinensis based on an intermediate tooth and three fragmentary specimens from the Castle Hayne Fm (Sequence 2, Lutetian) of North Carolina. Using an intermediate tooth as a type specimen is certainly a questionable practice, however Odontaspis teeth from these sediments (Fig. & ) indeed differ greatly with the typical winkleri tooth-designs (Fig. & ) from Europe. This author found no basis for synonymizing carolinensis with winkleri and accepts their unexplained and un-argued determination. Collectors of this fauna must place close attention to tooth-design, because there is functional convergence between the upper laterals of O. carolinensis and those of Brachycarcharias cf lerichei.
Lee Creek yields teeth that were were traditionally ascribed to Carcharias reticulata (PROBST, 1879). Purdy et al (2001) rejected that identification and ascribed these teeth to Odontaspis cf acutissma (AGASSIZ, 1844). Their arguments that these teeth should be deemed Odontaspis appeared valid, but their rejection of the specific name reticulata was problematic. On this webpage, these teeth are ascribed to O. reticulata. Teeth of this genus O. aff ferox have been found at Lee Creek (Mio-Pliocene of North Carolina).
Becker, M., Chamberlain, J. and Terry, O., 2004. Chondrichthyans from the Fairpoint Member of the Fox Hills Formation (Maastrichtian), Meade County, South Dakota. Jrnl. Vert. Paleo., 24(4):780-793.
Becker, M, Chamberlain, J and Wolf, G., 2006. Chondrichthyans from the Arkadelphia Formation (Upper Cretaceous: Upper Maastrichtian) of Hot Spring County, Arkansas. Journal of Paleontology; 80:4; pp 700-716
Cappetta, H., 1987. Chondrichthyes II. Mesozoic and Cenozoic Elasmobranchii. In: Handbook of Paleoichthyologie, vol. 3b, Gustav Fischer Verleg, Stuttgart, 193 pp.
Cappetta, H. and Case, G., 1975. Contribution ŕ l'étude des sélaciens du groupe Monmouth (Campanien - Maestrichtian) du New Jersey. Palaeontographica Abteilung A, 151:1-46.
Case.G. and Borodin, P., 2000, A Middle Eocene Selachin Fauna from the Castle Hayne Limestone Formation of Duplin County, NC, Munchner Geowiss. Abh.. 39:17-32.
Case, G. and Cappetta, H.. 1997. A new selachian fauna from the late Maastrichtian of Texas. Münchener Geowissenschaften Abhandungen 34:131-189.
Compagno, L., 2001. Sharks of the World, an annotated and illustrated catalogue of shark species known to date - Bullhead, mackerel & carpet sharks. FAO Species Catalogue for Fishery Purposes, No 1, Vol 2. FAO Rome. 269pp.
Kent, B., 1994. Fossil Sharks of the Chesapeake Region. Egan Rees & Boyer, Maryland. 146 pp
Purdy, R., Schneider, V., Appelgate, S., McLellan, J., Meyer, R. & Slaughter, R., 2001. The Neogene Sharks, Rays, and Bony Fishes from Lee Creek Mine, Aurora, North Carolina. In: Geology and Paleontology of the Lee Creek Mine, North Carolina, III. C. E. Ray & D. J. Bohaska eds. Smithsonian Contributions to Paleobiology, No 90. Smithsonian Institution Press, Washington D.C. pp. 71-202.
Ward, D. and Wiest, R., 1990. A checklist of Palaeocene 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.