Hemiscyllium

Summary

Hemiscyllium is a genus of sharks in the family Hemiscylliidae.

Hemiscyllium
Hemiscyllium ocellatum
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Subdivision: Selachimorpha
Order: Orectolobiformes
Family: Hemiscylliidae
Genus: Hemiscyllium Species See text Overview edit

Hemiscyllium sharks of the family Hemiscylliidae are also known as walking sharks,[1] bamboo sharks, and Epaulette sharks. These small, nocturnal, benthic dwelling swimmers have evolved to be able to 'walk', or use their fins to propel themselves over rocks, into pools, or into small crevices in their habitats.[2][3] Research from the School of Biomedical Sciences at the University of Queensland in Australia[1] has determined that this genus most recently split from the genus Chiloscyllium around 44 million years ago.[2] This genus is confined to tropical waters off Australia, Papua New Guinea, and Indonesia,[2] but an individual from this genus, possibly representing an undescribed species, has been photographed in the Seychelles.[4] They have short snouts with nostrils placed almost at the tip, well-elevated eyes, and supraorbital ridges. The mouth is closer to the tip of the snout than the eyes and lacks the connecting dermal fold across the chin. The pectoral and pelvic fins are thick and heavily muscular. Either a black hood on the head or a large black spot on the sides of the body is present,[5] though juveniles often are strongly marked with dark spots/bars. This shark family can survive around two hours out of water without any internal damage, can tolerate high levels of CO2, and are hypoxia and anoxia tolerant.[6]

Adaptations edit

Epaulette sharks live in shallow waters near reefs, tidepools or islands and are currently only found in the Western South Pacific.[7] Epaulette sharks use their fins to crawl inside small crevices or holes while hunting for small prey and escaping larger predators.[2] Each species in this genus also possesses a distinct black 'eye' spot behind its pectoral fins to deter predators by giving the appearance of a very large eye.[7] Neonate and juvenile epaulette sharks are born with lighter color markings and slightly different patterns, but their colors darken as they mature, with patterns shifting to mimic its environment.[7]

List of species edit

Nine recognized species are in this genus:[8][9]

References edit

  1. ^ a b "Walking sharks discovered in the tropics". UQ News. The University of Queensland. 2020-01-21.
  2. ^ a b c d Dudgeon, Christine L.; Corrigan, Shannon; Yang, Lei; Allen, Gerry R.; Erdmann, Mark V.; Fahmi; Sugeha, Hagi Y.; White, William T.; Naylor, Gavin J. P. (2020). "Walking, swimming or hitching a ride? Phylogenetics and biogeography of the walking shark genus Hemiscyllium" (PDF). Marine and Freshwater Research. 71 (9): 1107. doi:10.1071/mf19163. ISSN 1323-1650.
  3. ^ Allen, Gerald R.; Erdmann, Mark V.; White, William T.; Fahmi; Dudgeon, Christine L. (2016-11-02). "Review of the bamboo shark genus Hemiscyllium (Orectolobiformes: Hemiscyllidae)". Journal of the Ocean Science Foundation. 23: 51–97. doi:10.5281/zenodo.164197.
  4. ^ Debelius, H. (1993). Indian Ocean Tropical Fish Guide. Aquaprint Verlags GmbH. ISBN 3-927991-01-5
  5. ^ Compagno, Leonard J.V. (1984). Sharks of the World: An Annotated and Illustrated Catalogue of Shark Species Known to Date. Rome: Food and Agriculture Organization. ISBN 92-5-101384-5.
  6. ^ Porter, Marianne E; Hernandez, Andrea V; Gervais, Connor R; Rummer, Jodie L (2022-07-27). "Aquatic Walking and Swimming Kinematics of Neonate and Juvenile Epaulette Sharks". Integrative and Comparative Biology. 62 (6): 1710–1724. doi:10.1093/icb/icac127. ISSN 1540-7063.
  7. ^ a b c Allen, Gerald R.; Erdmann, Mark V.; White, William T.; Fahmi; Dudgeon, Christine L. (2016-11-02). "Review of the bamboo shark genus Hemiscyllium (Orectolobiformes: Hemiscyllidae)". Journal of the Ocean Science Foundation. 23: 51–97. doi:10.5281/zenodo.164197.
  8. ^ Froese, Rainer and Pauly, Daniel, eds. (2013). Species of Hemiscyllium in FishBase. April 2013 version.
  9. ^ a b Allen, G.R.; Erdmann, M.V. & Dudgeon, C.L. (2013). "Hemiscyllium halmahera, a new species of Bamboo Shark (Hemiscylliidae) from Indonesia" (PDF). Aqua, International Journal of Ichthyology. 19 (3): 123–136.
  10. ^ a b Allen, Gerald R. & Erdmann, Mark V. (2008). "Two new species of bamboo sharks (Orectolobiformes: Hemiscylliidae) from Western New Guinea" (PDF). Aqua (Miradolo Terme). 13 (3–4): 93–108.
  11. ^ Allen, Gerald R. & Dudgeon, Christine L. (2010). "Hemiscyllium michaeli, a new species of Bamboo Shark (Hemiscyllidae) from Papua New Guinea". Aqua International Journal of Ichthyology. 16 (1): 19–30.