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As with modern sawfishes (), the sclerorhynchids had a flattened shark-like body with a spine-edged rostrum. They are well represented in Late Cretaceous (extending into the Palaeocene of Morocco) fossil records of the Tethys region, Americas, India and New Zealand; depending on genus they are known from skeletons or isolated rostral spines and/or oral teeth. The rostral spines were skin-mounted on the snout unlike the socket-mounted spines of the extant pristids.
In North America (East/Gulf Coast & Western Interior Seaway) the reported genera include:
Ankistrorhynchus CASIER 1964. A Santonian-Campanian genus from the Tethys, Cappetta and Case (1975a: 31, pl. 9, fig. 26) erected A. major for a single dmaged rostral spine from New Jersey -- it is difficult to take this seriously.
Borodinopristis CASE 1987 Case (1987) erected B. schwimmeri for rostral spines and oral teeth from the Campanian of Georgia. Manning & Dockery (1992: 32-33) included this species in the Late Cretaceous of Mississippi.
Ischyrhiza LEIDY 1856. This genus is widely reported from North America (Turonian-Maastrichtian) and numerous species have been erected.
Kiestus CAPPETTA & CASE 1999. The genus was created for (oral teeth only) a single species K. texanus (CAPPETTA & CASE 1975b) from the Turonian-Coniacian of Texas.
Onchopristis STROMER 1917. Dunkle 1948:173 reported O. cf numidus (HAUG 1905) from the Late Cretaceous of Woodbine Fm (Cenomanian), Texas; this material was subsequently renamed O. dunklei McNULTY & SLAUGHTER 1962 and has been reported by multiple authors from the Cenomanian-Santonian of Texas.
Case 1965 attributed rostral spines from the Colcraine Fm (Cenomanian), MN to this species. Cappetta (1987: 152) notes the temporal range of the genus to be Aptian - Cenomanian (possibly Maastrichtian).
Onchosaurus GERVAIS 1852a. Lehman (1989: 533) attributed three damaged rostral spines from San Carlos Fm. (Campanian), TX to
O. pharao (DAMES 1887).
Ptychotrygon JAEKEL 1894a. This genus is widely reported from North America (Cenomanian-Maastrichtian) and numerous species have been erected.
Pucapristis SCHAEFFER 1963a. This author's P. branisi from the Maastrichtian of Bolivia has been included based on oral tooth-design and relative proximity.
Sclerorhynchus WOODWARD 1899d. This genus has a rich Cenomanian-Maastrichtian record in Texas. First reported from NA by Slaughter & Steiner (1968), they attributed their Late Cretaceous Texas rostral spines to S. atavus WOODWARD 1889d. Meyer (1974, Turonian-Coniacian) and Welton & Farish (1993: 146, Coniacian-Campanian) included this design as Sclerorhynchus sp. in reporting on the Texas material. S. pettersi CASE & CAPPETTA 1997 was erected for rostral & oral material from the Kemp Clay (Maastrichtian), TX. In Cappetta & Case (1999: 36-37) they erected S. fanninensis which included Welton & Farish's Campanian S. sp and
S. priscus which included Meyers S. sp. 1. Becker et al (2004:788) reported Sclerorhynchus. sp from the Maastrichtian of South Dakota and Becker et al (2006:707) reported S. sp from the Maastrichtian of Arkansas.
Schizorhiza WEILER 1930. Dunkle (1948: 174) and Welton & Farish (1993: 145) reported Schizorhiza cf weileri SERRA 1930 from the Maastrichtian of Texas.
Texatrygon CAPPETTA & CASE 1999 These authors (1999: 41) erected T. copei based on oral teeth only from the Turonian-Coniacian of Texas.
Sclerorhynchid sp
There is certainly a well published record from Texas but less comfortably, taxa erected solely on the basis of either rostral spines or oral teeth. None of the oral teeth from the above list agrees well with the NC specimens (Fig. & ); and those which are closest display strong labial ornamentation (Sclerorhynchus. priscus, S. tanninensis & Texatrygon hooveri). Using Cappetta (1987), the closest designs are represented by
Sclerorhynchus atavus WOODWARD 1889d (p.156 fig 134d-h, again labial ornamentation)
but more closely to Ischyrhiza hartenbergeri CAPPETTA 1975a (p.149 fig 126k-o) from the Maastrichtian of Bolivia. Lacking supporting rostral spines but based on root design, these teeth will not be attributed to a specific taxon at this time.
Acknowledgements
A special thanks to Earl Manning for extensive reference material and lively discussions regarding this-tooth design.
Selected References
Becker, M., Chamberlain, J. and Terry, D., 2004. Chondrichthyans from the Fairpoint Member of the Fox Hills Formation (Maastrichtian), Meade County, South Dakota. Journal of Vertebrate Paleontology, 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., 1975a. Sur quelques sélaciens nouveaux du Crétacé supérieur de Bolivie (Amérique du Sud). Geobios, 8 (1): 5-24, 8 fig.
Cappetta, H., 1987. Chondrichthyes II. Mesozoic and Cenozoic Elasmobranchii. In: Handbook of Paleoichthyologie, vol. 3b, Gustav Fischer Verleg, Stuttgart, 193 pp.
Cappetta, H. & Case, G., 1975a. Contribution à l'étude des sélaciens du groupe Monmouth (Campanien - Maestrichtian) du New Jersey. Palaeontographica Abteilung A, 151:1-46.
Cappetta, H. & Case, G., 1975b.Sélaciens nouveaux du Crétacé du Texas. Geobios, 8 (4): 303-307, 6 fig.
Cappetta, H. and Case, G., 1999. Additions aux faunes de sélaciens du Crétacé du Texas (Albien supérieur-Campanien). Palaeoichthyologica, 9, 5-111.
Case, G., 1965. An Occurrence of the Sawfish, Onchopristis dunklei in the Upper Cretaceous of Minnesota. Journal, Minnesota Acad. Science, vol 32, p183
Case, G., 1987. Borodinopristis schwimmeri, a new Ganopristine sawfish from the Upper Blufftown Formation (Campanian) of the Upper Cretaceous of Georgia. Bull. NJ Acad. Sci, 32:1, pp 25-33.
Case, G. R., and H. Cappetta. 1997. A new selachian fauna from the late Maastrichtian of Texas. Muünchener Geowissenschaften Abhandungen 34:131-189.
Dunkle, D., 1948. On two previously unreported selaciens from the Upper Cretaceous of North America. Journal, Washington Academy of Sciences, vol 38 (5), pp 173-76.
Lehman, T., 1989. Giant Cretaceous sawfish (Onchosaurus) from Texas. Jornal of Paleontology 63(4), pp 533-535.
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.
McNulty, C and Slaughter, B., 1962. A new sawfish from the Woodbine Formation (Cretaceous) of Texas. Copeia (4): 775-777.
Meyer, R., 1974. Late Cretaceous elasmobranchs from the Mississippi and East Texas embayments of the Gulf Coastal Plain. Unpubl. PhD dissertation, Southern Methodist Univ., Dallas, xiv+419 p.
Schaeffer, B., 1963. Cretaceous fishes from Bolivia, with comments on Pristid evolution: Amer. Museum Noitates, no 2159, p1-20.
Slaughter, B and Steiner, M. 1968. Notes on the Rostral teeth of Ganopristine Sawfishes, with special reference to Texas material. Paleontological Notes. Journal of Paleontology, 42(1) pp 233-239.
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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