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Family Rhinidae Wedgefishes /Guitarfishes. Taxonomy. Order Rhiniformes (or Rajiformes?) Family Rhinidae (or Rhynchobatidae?) Genus Rhynchobatus R. djidennsis (giant guitarfish)* R.australiae (white-spotted guitarfish) R. laevis (smoothnose wedgefish)
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Family Rhinidae Wedgefishes /Guitarfishes
Taxonomy Order Rhiniformes (or Rajiformes?) Family Rhinidae (or Rhynchobatidae?) Genus Rhynchobatus R. djidennsis (giant guitarfish)* R.australiae (white-spotted guitarfish) R. laevis (smoothnose wedgefish) R. leubberti (African wedgefish) R. spp. nov. A (roughnose wedgefish) R. spp. nov. B (broadnose wedgefish)
Morphology seem to be intermediate between Pristidae and Rhinobatidae elongated rostrum (without saw) large, shark-like fins- 2 dorsal batoid-like cephalic pectoral fins
Morphology dorsoventrally flattened large spiracles near the eyes size: TL ~300cm R. australiae- color morphs in Indonesia different species? undescribed spp.A- “dwarf” species- 82cm TL
Habitat and Distribution Most: Indo-West-Pacific, especially Indonesia R. luebberti- E. Atlantic all species are inshore, coastal, usually ~35m deep found near sandy beaches (KwaZulu-Natal, S. Africa) and along reef edges
Reproduction mature at 150cm TL, 60cm TL at birth aplacental viviparous ~4 pups/litter R. australiae- up to 19 pups/litter probably low fecundity due to typical elasmo life history characteristics
Prey stomach contents: crab, bivalve molluscs
Conservation habitat destruction bycatch (prawn fishery, Indonesia and KwaZulu-Natal)
Conservation targeted fisheries (fins, meat, Indonesia, Tanzania) probably among most highly desired chondrichthyans high value fins, highly palatable meat
Conservation easily caught in bottom set gillnets, bottom trawls
Conservation “protective” shark nets (KwaZulu-Natal)- but many released alive life history characteristics females caught more than males
Conservation IUCN Redlist: all species vulnerable, R. leubberti- endangered (W. Africa) likely to see decreasing trends due to limited distribution, continuation of unregulated fishing
Literature Cited Compagno, L.J.V. & Marshall, A.D. 2006. Rhynchobatus luebberti. In: IUCN 2007. 2007 IUCN Red List of Threatened Species. <www.iucnredlist.org>. Downloaded on 04 November 2007. Compagno, L.J.V. & Marshall, A.D. 2006. Rhynchobatus sp. nov. A. In: IUCN 2007. 2007 IUCN Red List of Threatened Species. <www.iucnredlist.org>. Downloaded on 04 November 2007. Compagno, L.J.V. & Marshall, A.D. 2006. Rhynchobatus sp. nov. B. In: IUCN 2007. 2007 IUCN Red List of Threatened Species. <www.iucnredlist.org>. Downloaded on 04 November 2007. McAuley, R. & Compagno, L.J.V. 2003. Rhynchobatus laevis. In: IUCN 2007. 2007 IUCN Red List of Threatened Species. <www.iucnredlist.org>. Downloaded on 04 November 2007. McEachran, J.D. and N. Aschliman. 2004. Phylogeny of Batoidea. Pp. 79-114 in Biology of Sharks and Their Relatives (J.C. Carrier, J.A. Musick, and M.R. Heithaus, eds). CRC Press, Boca Raton. Stobutzki, I.C., M.J. Miller, D.S. Heales, and D.T. Brewer. 2002. Sustainability of elasmobranchs caught as bycatch in a tropical prawn (shrimp) fishery. Fish. Bull. 100: 800-821. White, W.T. and Dharmadi. 2007. Species and size compositions and reproductive biology of rays (Chondrichthyes, Batoidea) caught in target and non-target fisheries in eastern Inodnesia. J. Fish Biol. 70: 1809-1837 White, W.T. & McAuley, R. 2003. Rhynchobatus australiae. In: IUCN 2007. 2007 IUCN Red List of Threatened Species. <www.iucnredlist.org>. Downloaded on 04 November 2007.