Ontogenetic development of teeth in Lamna nasus (Bonnaterre, 1758) (Chondrichthyes : Lamnidae) and its implications for the study of fossil shark teeth
Author:
Purdy, Robert W.
Francis, M. P.
Object Type:
Smithsonian staff publication
Electronic document
Year:
2007
Topic:
Paleobiology
Natural History
Citation:
Journal of Vertebrate Paleontology, 27(4): 798-810.
Abstract:
Tooth development is traced in dentitions from 169 embryonic Lanina nasits (96-670 mm fork length [FL]), and 8 juvenile to adult L. nasits (67-300 cm FL). The teeth of these dentitions vary significantly in the attitudes and shapes of their crowns, and the forms of their roots. At some stages of their ontogeny they bear characters of carcha-rhiniform and alopiid shark teeth. and they may also bear ornamentation on their crowns. In early embryos, the teeth are conical with funnel-shaped roots and resemble skate dermal thorns, Raja spp. Tooth shape changes abruptly at about 350 mm FL to a late embryonic dentition, with very elongate lower anterior teeth, as in Pseudocarcharias. Adult teeth also exhibit significant morphological variation, and exhibit some characters that occur also in primitive neoselachians, such as Synechodus and Paraorthacodus. The importance of these tooth ontogenetic and morphological variations for the study of fossil shark teeth is presented, and a generic diagnosis is offered for juvenile and adult Lanina teeth.
Report of the Second FAO Ad Hoc Expert Advisory Panel for the Assessment of Proposals to Amend Appendices I and II of CITES Concerning Commercially-exploited Aquatic Species : Rome, 26-30 March 2007
Second FAO Ad Hoc Expert Advisory Panel for the Assessment of Proposals to Amend Appendices I and II of CITES Concerning Commercially-exploited Aquatic SpeciesFAO Ad Hoc Expert Advisory Panel for the Assessment of Proposals to Amend Appendices I and II of CITES Concerning Commercially-exploited Aquatic Species
Author:
FAO Ad Hoc Expert Advisory Panel for the Assessment of Proposals to Amend Appendices I and II of CITES Concerning Commercially-exploited Aquatic Species (2nd : 2007 : Rome, Italy)
Food and Agriculture Organization of the United Nations
Considers seven proposals for inclusion of species under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), Appendix II: Lamna nasus (porbeagle shark); Squalus acanthias (spiny dogfish); all species in family Pristidae (sawfishes); Anguilla anguilla (European eel); Pterapogon kauderni (Banggai cardinalfish); and Panulirus argus and P. laevicauda of the Brazilian lobster population genus Corallium (red/pink corals). The objectives of the Panel were to: assess each proposal from a scientific perspective in accordance with the CITES biological listing criteria (Resolution Conf. 9.24 [Rev. CoP13]); and comment, as appropriate, on technical aspects of the proposal in relation to biology, ecology, trade and management issues, as well as, to the extent possible, the likely effectiveness for conservation