Broad-nosed seven-gill shark
| Broad-nosed seven-gill shark | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Broad-nosed seven-gill shark ( Notorynchus cepedianus ) |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name of the genus | ||||||||||||
| Notorynchus | ||||||||||||
| Ayers , 1855 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Notorynchus cepedianus | ||||||||||||
| ( Péron , 1807) |
The broad-nosed seven-gill shark ( Notorynchus cepedianus ) is a large shark from the family of the comb -toothed sharks (Hexanchidae). It is the only species in the genus Notorynchus . Some authors also place it in a separate family, the Notorhynchidae.
Appearance
The up to three meters long and up to 107 kg heavy sharks have a silvery-gray to red-brown back and a lighter belly. Small dark spots cover the whole body. The name is derived from the seven gill slits, which all lie in front of the approach of the pectoral fin and get smaller and smaller from front to back. The broad-nosed seven-gill shark shares this characteristic with the pointed-head seven-gill shark . The small dorsal fin sits far back. The teeth of the upper jaw are small and pointed. In the lower jaw, the teeth are comb-shaped and have small additional points after a point. They are much larger than those of the upper jaw.
distribution
With the exception of the Mediterranean and the North Atlantic, the broad-nosed seven-gill shark lives worldwide in tropical, but especially in temperate seas, above the bottom of the continental shelf at depths of 0 to 570 meters. They are not common anywhere.
Way of life
The sharks live alone in the summer in shallow water, over sandy bottoms or near kelp forests . In the cold season they retreat to deep water. They feed on smaller sharks, rays , bony fish , lampreys , crustaceans , mollusks and seals .
Broad-nosed seven-gill sharks are viviparous. After a gestation period of one year, they have 82 to 95 young per litter. The fry are born in shallow, sheltered bays and are then half a meter long. Males reach sexual maturity at 1.5 meters and females at 1.9 to 2.1 meters.
The sharks are considered to be potentially aggressive and dangerous. They may have been involved in shark attacks on the coast of South Africa , California, and New Zealand . Animals kept in show aquariums attacked diving nursing staff.
literature
- Hans A. Baensch / Robert A. Patzner: Mergus Sea Water Atlas Volume 6 Non-Perciformes (Non-Perciformes) , Mergus-Verlag, Melle, ISBN 3-88244-116-X
Web links
- www.hai.ch Broad-nosed seven-gill shark ( Notorynchus cepedianus )
- Broad-nosed seven-gill shark on Fishbase.org (English)
- Notorynchus cepedianus in the endangered Red List species the IUCN 2006. Posted by: Compagno, Hunting Association, 2007. Retrieved on August 20 of 2006.
Individual evidence
- ^ Integrated Taxonomic Information System Notorynchus cepedianus
- ↑ http://www.heute.de/ZDFheute/inhalt/30/0,3672,8024030,00.html ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.
