Abstract
Rostral tooth counts of Pristis pectinata specimens from museum collections, research surveys, and fisheries activities were examined to provide information on sexual dimorphism, bilateral asymmetry, and to aid in the resolution of the taxonomic uncertainty that surrounds the Pristidae. Counts were taken from 105 smalltooth sawfish captured in Florida and Georgia, USA, from 1834 to 2007. The number of rostral teeth present was 22 to 29 per side and 45 to 56 in total. These counts were more constrained, and mean values lower, than historically reported for this species in the literature. Pristis pectinata rostral tooth counts exhibited sexual dimorphism, with males on average having more rostral teeth than females. Bilateral asymmetry in rostral tooth counts was displayed in 73% of individuals, with no consistent side on which the greatest count occurred. No significant difference between left and right side rostral tooth counts was found.References
Adams, W.F., Fowler, S.L., Charvet-Almeida, P., Faria, V.V., Soto, J. & Furtado-Neto, M.A.A. (2006) Pristis pectinata. In: IUCN 2007. 2007 IUCN Red List of Threatened Species. Available from www.iucnredlist.org. (31 March 2008).
Bigelow, H.B. & Schroeder, W.C. (1953) Sawfishes, guitarfishes, skates, rays, and chimeroids. Fishes of the Western North Atlantic. Memoirs of the Sears Memorial Foundation for Marine Research, 1, 1–514.
Boschung, H. (1979) The Batoids of the Gulf of Mexico. Nature Notebook. University of Alabama, Alabama Museum of Natural History, 5, 12 pp.
Braccini, J.M. & Chiaramonte, G.E. (2002) Intraspecific variation in the external morphology of the sand skate. Journal of Fish Biology, 61, 959–972.
Casselmann, S.J. & Schulte-Hostedde, A.I. (2004) Reproductive roles predict sexual dimorphism in internal and external morphology of lake whitefish, Coregonus clupeaformis. Ecology and Freshwater Fish, 13, 217–222.
Cervigón, F. & Alcalá, A. (1999) Los Peces Marinos de Venezuela. Vol. 5. Tiburones y Rayas. Fundación Museo del Mar, 230 pp.
Compagno, L.J.V. (1999) Checklist of living elasmobranchs. In: Hamlett, W.C. (Ed.) Sharks, Skates and Rays, the Biology of Elasmobranch Fishes. John Hopkins University Press, Baltimore, MD, pp. 471–498.
Compagno L.J.V. (2005) Checklist of living elasmobranchs. In:Hamlett, W.C. (Ed.) Reproductive biology and phylogeny of Chondrichthyes: Sharks, batoids and chimaeras. University of Queensland, Science Publishers, 503–548.
Compagno, L.J.V. & Cook, S.F. (1995) The exploitation and conservation of freshwater elasmobranchs: status of taxa and prospects for the future. In: Oetinger, M.I. & Zorzi, G.D. (Eds.) The Biology of Freshwater Elasmobranchs, a Symposium to Honor Thomas B. Thorson. Journal of Aquariculture and Aquatic Sciences, VII, 62–90.
Compagno, L.J.V. & Last, P.R. (1999) Pristiformes:Pristidae. In: Carpenter, K.E. & Niem, V.H. (Eds.) FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Volume 3. Batoid fishes, chimaeras and bony fishes part 1 (Elopidae to Linophrynidae) pp:1410–1417. FAO, Rome.
Eschmeyer, W. (1998) Catalog of Fishes. California Academy of Sciences Special Publication 1, Anaheim, California, 2905 pp.
Hoese, H.D. & Moore, R.H. (1998) Fishes of the Gulf of Mexico, Texas, Louisiana, and Adjacent Waters. Texas A&M University Press, College Station, 422 pp.
Hubbs, C.L. & Ishiyama, R. (1968) Methods for the taxonomic study and description of skates (Rajidae). Copeia, 1968:483–491.
Hubbs, C.L. & Hubbs L.C. (1945) Bilateral asymmetry and bilateral variation in fishes. The Michigan Academy of Science, Arts, and Letters Papers, 30, 229–310.
Ishihara, H., Taniuchi, T. & Shimizu, M. (1991) Sexual dimorphism in number of rostral teeth in the sawfish, Pristis microdon collected from Australia and Papua New Guinea. University Museum, University of Tokyo, Nature and Culture, 3, 83–89.
IUCN (2006) 2006 IUCN Red List of Threatened Species. Available from: http://www.iucnredlist.org. (03 May 2007).
Jordan, D.S. & Evermann, B.W. (1896) The Fishes of North and Middle America. Bulletin of the United States National Museum Number 47, Government Printing Office, Washington.
Kajiura, S.M. & Tricas T.C. (1996) Seasonal dynamics of dental sexual dimorphism in the Atlantic stingray Dasyatis sabina. The Journal of Experimental Biology, 199, 2297–2306.
Last, P.R. & Stevens J.D. (1994) Sharks and Rays of Australia. CSIRO. Melbourne, 513 pp.
Martin, R.A. (2005) Conservation of freshwater and euryhaline elasmobranchs: a review. Journal of the Marine Biological Association of the United Kingdom, 85, 1049–1073.
McEachran, J.D. (1977) Reply to “sexual dimorphism in skates (Rajidae)”. Evolution, 31, 218–220.
McEachran, J.D. (1982) Revision of the South American skate genus Sympterygia (Elasmobranchii: Rajiformes). Copeia, 4, 867–890.
McEachran, J.D. & Fechhelm, J.D. (1998) Fishes of the Gulf of Mexico, Volume 1: Myxiniformes to Gasterosteiformes. University of Texas Press, Austin, 1112 pp.
Poulakis, G.R. & Seitz, J.C. (2004) Recent occurrence of the smalltooth sawfish, Pristis pectinata (Elasmobranchiomorphi: Pristidae), in Florida Bay and the Florida Keys, with comments on sawfish ecology. Florida Scientist, 67, 27–35.
Robillard, M. & Séret, B. (2006) Cultural importance and decline of sawfish (Pristidae) populations in West Africa. Cybium, 30(4), 23–30.
Schwartz, F.J. (2003) Bilateral asymmetry in the rostrum of the smalltooth sawfish, Pristis pectinata (Pristiformes: Family Pristidae). Journal of the North Carolina Academy of Science, 119(2), 41–47.
Seitz, J.C. & Poulakis, G.R. (2002) Recent occurrences of sawfish (Elasmobranchiomorphi: Pristidae) along the southwest coast of Florida (USA). Florida Scientist, 65(4), 256–266.
Simpfendorfer, C.A. (2002) Smalltooth sawfish: the USA’s first endangered elasmobranch? Endangered Species Update, 19(3), 45–49.
Simpfendorfer, C.A. (2005) Threatened fishes of the world: Pristis pectinata Latham, 1794 (Pristidae). Environmental Biology of Fishes, 73, 20.
Simpfendorfer, C.A. & Wiley, T.R. (2005) Determination of the distribution of Florida’s remnant sawfish population and identification of areas critical to their conservation. Final Report. Florida Fish and Wildlife Conservation Commission, Tallahassee, Florida.
Slaughter, B.H. & Springer, S. (1968) Replacement of rostral teeth in sawfishes and sawsharks. Copeia, 1968(3), 499–506.
Snelson, F.F. & Williams, S.E. (1981) Notes on the occurrence, distribution, and biology of elasmobranch fishes of the Indian River Lagoon system, Florida. Estuaries, 4(2), 110–120.
Thorburn, D.C., Morgan, D.L., Rowland, A.J. & Gill, H.S. (2007) Freshwater sawfish Pristis microdon Latham, 1794 (Chondrichthyes:Pristidae) in the Kimberley region of Western Australia. Zootaxa, 1471, 27–41.
Thorson, T.B. (1973) Sexual dimorphism in number of rostral teeth of the sawfish, Pristis perotteti Müller and Henle, 1841. Transactions of the American Fisheries Society, 102(3), 612–614.
Thorson, T.B. (1976) Observations on the reproduction of the sawfish, Pristis perotteti, in Lake Nicaragua, with recommendations for its conservation. In: Thorson, T.B. (Ed.) Investigations of the Ichtyofauna of Nicaraguan Lakes. School of Life Sciences, University of Nebraska-Lincoln, Lincoln, pp. 641–650.
Wiley, T.R. & Simpfendorfer C.A. (2007) The ecology of elasmobranchs occurring in the Everglades National Park, Florida: Implications for conservation and management. Bulletin of Marine Science, 80(1), 171–189.
Zorzi, G.D. (1995) The biology of freshwater elasmobranchs: an historical perspective. In: Oetinger, M.I. & Zorzi, G.D. (Eds.) The Biology of Freshwater Elasmobranchs, a Symposium to Honor Thomas B. Thorson. Journal of Aquariculture and Aquatic Sciences, VII, 10–31.