Raja binoculata
| Raja binoculata | ||||||||||||
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Raja binoculata |
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| Scientific name | ||||||||||||
| Raja binoculata | ||||||||||||
| Girard , 1855 |
Raja binoculata is the largest representative of the real rays (Rajidae) on the Pacific coast of North America. It occurs in the northern Pacific from Cape Navarin south of the Russian Chukchi Peninsula on the Bering Strait up to the level of Isla de Cedros off the coast of Lower California .
features
Raja binoculata is usually 1.80 meters, a maximum of 2.40 meters long and can reach a maximum weight of 91 kg. The front edge of the body disc is slightly concave inward, the head is pointed. Its two small dorsal fins lie far back on its tail. A caudal fin is missing. There is a meaty keel on either side of the tail. The pelvic fins are only slightly indented. Some thorns are on the eyes, in adult animals they are covered by skin. Another thorn is located in the middle of the body, a row of thorns above the pelvic fins, it can also be missing, and on the top of the tail. Otherwise the upper side of the body is without larger thorns, with the exception of the small denticles of adult specimens. The whitish, sometimes with dark spots, underside is almost completely smooth. The upper side of Raja binoculata is brown, gray, red-brown or olive-colored, often with rosette-like white spots, dark marbling and two conspicuous eye spots .
Way of life
Raja binoculata lives at depths of three to 800 meters on sandy and silty sea beds. It feeds on fish and crustaceans and often digs itself completely into the ground. Like all real rays it is egg-laying ( oviparous ). The eggs are rough, elongated horn capsules that are 22.8 to 30.5 cm long and 11 to 19.4 cm wide and have stiff, pointed horns at the corners.
literature
- Eschmeyer, Herald, Hamann: Pacific Coast Fishes , Peterson Field Guides, ISBN 0-395-33188-9
Web links
- Raja binoculata on Fishbase.org (English)
- Beringraja binoculata inthe IUCN 2013 Red List of Threatened Species . Listed by: Ellis, J. & Dulvy, N., 2005. Retrieved November 3, 2013.