Horn shark
Horn shark | ||||||||||||
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Horn shark ( Heterodontus francisci ) |
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Heterodontus francisci | ||||||||||||
( Girard , 1855) |
The horn shark ( Heterodontus francisci ) is a bull head shark up to 120 cm long . It occurs in the temperate to subtropical coastal areas off the North American Pacific coast in the area of southern California , Baja California and Mexico .
Appearance and characteristics
The horn shark has an average body length of about 100 cm, but can also reach body lengths of up to 120 cm. It has a gray to light brown body color and is marked by numerous small dark points over the head, body and tail.
The shark has a cylindrical body with a conical head. In contrast to the other bull head sharks (with the exception of the crested bull head shark ), the eye bulges are very pronounced. It has an anal fin and two dorsal fins , both of which are thorny, and five comparatively long gill slits with a small spray hole (spiraculum) below the eye.
Way of life
The horn shark is a predominantly nocturnal species in the area of the continental shelf, where it lives close to the sea floor to the surface at a depth of 2 to 11 m. However, it can also occur in deeper sea regions down to a depth of 150 m. The animals prefer stony ground with good hiding spots, in which they spend the day. They feed primarily on bottom-living invertebrates, including in particular sea urchins as well as crabs and mussels , which it can break open with its plaster teeth. On the sea floor they move “walking” by using their pectoral fins accordingly.
Like all bull head sharks, it is egg-laying ( oviparous ) and lays 2 spiral-shaped eggs at intervals of about every 2 weeks (aquarium observation ) over a period of about 4 months from about 2 weeks after mating. The young sharks hatch after about 7 to 9 months with a size of about 15 cm. The animals reach sexual maturity at a length of about 60 cm.
distribution
The horn shark occurs in the temperate to subtropical coastal areas off the North American Pacific coast in the area of southern California , Baja California and Mexico . Further occurrences off Peru and Chile are assumed.
literature
- Leonard Compagno , Marc Dando, Sarah Fowler: Sharks of the World . Princeton University Press , Princeton and Oxford 2005, ISBN 978-0-691-12072-0 , pp. 150-151.
Web links
- Horn shark on Fishbase.org (English)
- Entry in the database of the Shark Foundation
- Heterodontus francisci inthe IUCN 2013 Red List of Threatened Species . Listed by: Carlisle, AB, 2006. Retrieved November 5, 2013.