Contributions to the study of the comparative morphology of teeth and other relevant ichthyodorulites in living supraspecific taxa of Chondrichthyan fishes. Part A. Selachii. 1b: Order: Hexanchiformes - Family: Chlamydoselachidae. 5: Order: Heterodontiformes - Family: Heterodontidae. 6: Order: Lamniformes - Families: Cetorhinidae, Megachasmidae; Addendum 1 to 3: Order Squaliformes; Addendum 1 to 4: Order: Orectolobiformes; General Glossary; Summary part A
Herman, J.; Hovestadt-Euler, M.; Hovestadt, D.C. (1993). Contributions to the study of the comparative morphology of teeth and other relevant ichthyodorulites in living supraspecific taxa of Chondrichthyan fishes. Part A. Selachii. 1b: Order: Hexanchiformes - Family: Chlamydoselachidae. 5: Order: Heterodontiformes - Family: Heterodontidae. 6: Order: Lamniformes - Families: Cetorhinidae, Megachasmidae; Addendum 1 to 3: Order Squaliformes; Addendum 1 to 4: Order: Orectolobiformes; General Glossary; Summary part A. Bull. Kon. Belg. Inst. Natuurwet. Biologie 63: 185-256
In: Bulletin van het Koninklijk Belgisch Instituut voor Natuurwetenschappen. Biologie = Bulletin de l'Institut Royal des Sciences Naturelles de Belgique. Biologie. Koninklijk Belgisch Instituut voor Natuurwetenschappen: Bruxelles. ISSN 0374-6429, more
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Elasmobranchii - Selachii - Chlamydoselachidae - Heterodontidae - Cetorhinidae - Megachasmidae - Squalidae - Orectolobidae - Odontology - Systematics |
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- Herman, J.
- Hovestadt-Euler, M.
- Hovestadt, D.C.
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| Abstract |
The morphology of the microteeth of the following taxa is described and illustrated with SEM-photographs in order to elucidate the interrelationships within the shark orders and families concerned and also from odontological point of view. Contribution 1b: The monotypic single genus of the hexanchiform Chlamydoselachidae. The tooth morphology of C. anguineus is compared with that of taxa of the only other hexanchiformes. The dental histology is commented on, and the dental vascular type is re-examined in order to understand the root form. The results are summarized in an odontological diagnosis for the genus. Investigational results on dental morphology, histology and vascularization recommend a reconsideration of the systematic position of the Chlamydoselachidae, which show a closer relation to Orectolobiformes than to Hexanchidae. Contribution 5: The three genera Tropidodus, Gyropleurodus and Heterodontus of the heterodontiform family Heterodontidae as once proposed by Gill, 1862. The differences in tooth morphology are only of interspecific signification. Contribution 6: The genera of the monotypic families Cetorhinidae and Megachasmidae. The morphology of the small teeth in both families is characteristic for filter-feeders. Cetorhinus exhibits irregular size and shape of its small teeth and a distinct ontogenetic heterodonty in its dentition. Megachasma, in contrast, shows small teeth of equal size and shape indicating a relatively recent adaptation to filter-feeding. Contribution 3, addendum 1: The squalid species Scymnodon squamulosus and Scymnodon obscurus attributable to the genus Zameus, proposed by Jordan and Fowler in 1903 and revalidated by Taniuchi and Garrick in 1986. Odontological investigations indicate a synonymy of Zameus and Scymnodalatias with Scymnodon. Contribution 4, addendum 1: The type species of the monotypic orectolobid genus Sutorectus. The results are summarized in a diagnosis for the genus and offer hardly any odontological arguments for distinguishing Sutorectus from Orectolobus. |
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