Atlantic dwarf shark
| Atlantic dwarf shark | ||||||||||||
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Two Atlantic pygmy sharks ( C. porosus ) caught in the Gulf of Mexico |
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| Scientific name | ||||||||||||
| Carcharhinus porosus | ||||||||||||
| ( Ranzani , 1839) |
The Atlantic minke shark ( Carcharhinus porosus ) is a species of the genus Carcharhinus within the Requiem sharks (Carcharhinidae). The distribution area of the Atlantic minke shark extends along the Atlantic coastal areas of Central and South America.
Appearance and characteristics
The Atlantic dwarf shark is a comparatively small and slender shark for the genus, with an average size of less than 150 cm. He has a gray back without any noticeable markings and a white belly. The fin tips can be darker to black in color, the tips of the anal fin are occasionally reddish in color.
It has an anal fin and two dorsal fins . The first dorsal fin is comparatively large and upright, it lies over the middle of the free edge of the pectoral fin. There is no interdorsal ridge . The second dorsal fin is much smaller and, compared to other species, is closer to the tail. The pectoral fins are relatively wide. Like all species of the genus, the animals have five gill slits and no injection hole .
Way of life
The Atlantic minke shark lives very ground-oriented near the coast in the area of the continental shelf as well as on island bases at depths of up to 40 m. It prefers muddy subsoil and can also occur in estuaries with a lower salinity .
nutrition
It feeds predatory on various bony fish such as sardines , herrings , flatfish , but can also prey on smaller sharks ( sharp-nosed sharks , young hammerheads ).
Reproduction
Like other species of the genus, it is viviparous and forms a yolk sac placenta ( placental viviparous ). The females give birth to 2 to 7 young animals after a gestation period of around 10 months. The young sharks have a size of about 30 to 40 centimeters and are born near the coast. The very slowly growing animals reach sexual maturity at a length of about 80 cm.
distribution
The distribution area of the Atlantic minke shark extends along the Atlantic coastal areas of Central and South America from the northern Gulf of Mexico , along the coast of Central America to Brazil . The small sharks of the genus Carcharhinus that occur on the Pacific side of Central and South America and until recently were assigned to Carcharhinus porosus are now assigned to the species Carcharhinus cerdale again .
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. 304-305.
Web links
- Species portrait on hai.ch
- Atlantic dwarf shark on Fishbase.org (English)
- Carcharhinus porosus inthe IUCN 2013 Red List of Threatened Species . Posted by: Lessa, R., Almeida, Z., Santana, FM, Siu, S. & Perez, M., 2006. Retrieved December 4, 2013.