Weasel sharks

Weasel sharks
Hook tooth shark ( Chaenogaleus macrostoma )
Systematics
Subclass : Euselachii Subclass : Plate gill (Elasmobranchii) without rank: Sharks (selachii) Superordinate : Galeomorphii Order : Ground Sharks (Carcharhiniformes) Family : Weasel sharks
Scientific name
Hemigaleidae
Hasse , 1879

Australian weasel shark ( Hemigaleus australiensis )

Crescent Weasel Shark ( Hemigaleus microstoma )

Fossil Shark ( Hemipristis elongata )

The weasel sharks (Hemigaleidae) are a family of relatively small ground sharks (Carcharhiniformes). They live in the eastern tropical Atlantic , possibly as far as the coast of New England , and in the Indo-Pacific , always close to the coast, near the continents , not in the central Pacific .

features

Weasel sharks are slim, usually have a rather elongated snout and grow to be 0.5 to 2.40 meters long. Most species reach a length of one meter. Your eyes are oval in shape and horizontal, the spray hole is small. Weasel sharks have two medium-sized, stingless dorsal fins and one anal fin . The first dorsal fin sits clearly in front of the pelvic fin attachment . The heterocerke caudal fin has a wave-like upper edge and a well-developed lower lobe. There are pit-like depressions on the tail fin stalk. The labial folds in the area of ​​the corners of the mouth are medium-sized. The intestine has spiral folds .

Way of life

Weasel sharks live at depths of up to 100 meters. They mostly eat small bony fish , small sharks and rays , crustaceans and echinoderms , some species mainly feed on cephalopods .

Genera and species

There are eight species belonging to four genera.

• Genus: Chaenogaleus Gill, 1862
  • Hook tooth shark ( Chaenogaleus macrostoma (Bleeker, 1852) )
• Genus: Crescent Weasel Sharks ( Hemigaleus Bleeker, 1852 )
  • Australian weasel shark ( Hemigaleus australiensis White, Last & Compagno, 2005 )
  • Crescent Weasel Shark ( Hemigaleus microstoma Bleeker, 1852 )
• Genus: Hemipristis Agassiz, 1843
  • Fossil shark ( Hemipristis elongata (Klunzinger, 1871) )
• Genus: Sharp- nosed Weasel Sharks ( Paragaleus Budker, 1935 )
  • Whitetip weasel shark ( Paragaleus leucolomatus Compagno & Smale, 1985 )
  • Atlantic weasel shark ( Paragaleus pectoralis (Garman, 1906) )
  • Slender weasel shark ( Paragaleus randalli Compagno, Krupp & Carpenter, 1996 )
  • Smooth-toothed weasel shark ( Paragaleus tengi (Chen, 1963) )

literature

• Joseph S. Nelson : Fishes of the World . John Wiley & Sons, 2006, ISBN 0-471-25031-7 .

Web links

Commons : Hemigaleidae  - Collection of images, videos and audio files

• Weasel Sharks on Fishbase.org (English)