Raja inornata (lat.) Is a species of cartilaginous fish of the rhombic stingrays of the stingrays. They live in temperate waters of the east-central and northeastern Pacific Ocean between 49 ° C. w. and 20 ° c. W and between 126 ° C. D. and 106 ° C. They are found at a depth of up to 1600 m. Their large, flattened pectoral fins form a rhombic disk with a slightly elongated snout. The maximum recorded length is 76 cm. Eggs are laid. They are the subject of fishing [1] [2] [3] .
| Raja inornata |
| Scientific classification |
|---|
| No rank : | Bilateral symmetrical |
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| International scientific name |
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Raja inornata Jordan & Gilbert , 1881 |
| Synonyms |
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- Raja jordani garman, 1885
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| Security status |
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Least ConcernedIUCN 3.1 Least Concern : 161466 |
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The species was first scientifically described in 1881 [4] . These stingrays are often confused with other representatives of the genus living in this arel [2] . Species epithet comes from lat. in - “not” and lat. ornatus - "richly decorated."
These demersal ramps live along the west coast of North America from the Strait of Juan de Fuca , British Columbia , along the shores of Canada and the United States to Baja California , Mexico . They are found on the continental shelf at a depth of 17 to 1600 m. In the waters of the United States, they are mainly kept at a depth of 58–231 m at a water temperature of 8.2–9.6 ° C, and prevail in central California at a depth of an average of 105 m [2 ] [3] .
The broad and flat pectoral fins of these slopes form a rhombus disk with an elongated snout and rounded edges. On the ventral side of the disc are 5 gill slits, nostrils and mouth. On the long tail there are lateral folds [1] . Orbital and scapular spines are absent. Along the tail lies the middle row of spines, which sometimes reaches the middle of the disk. Basically, the surface of the disk is smooth, not counting the few teeth. The ventral surface is smooth. The dorsal surface is olive-brown in color, sometimes with dark dots and circles around the eyes [5] . The maximum recorded length is 76 cm [3] .
Like other rhombic, these stingrays lay eggs enclosed in a rigid horn capsule with protrusions at the ends. Embryos feed exclusively on yolk [3] . In the Gulf of California, males and females reach puberty with a length of 45 cm and 50 cm, at the age of 2.4 and 2.9 years, respectively. The maximum life expectancy is estimated at 7 years for males and 9 years for females. The peak of the breeding season is observed in September-November, the cycle is annual. The size of newborns is 15-23 cm. The generation duration is estimated at 5.95 years [2] .
These skates are not subject to targeted fishing. Earlier in the United States, these skates came across as by- catch and were targeted by longlines and trawls. In California, the population has declined significantly. Meat is consumed as food. Currently, California’s coast has 29 protective areas with a total area of about 204 square meters. km The International Union for Conservation of Nature has assigned the conservation status of “Least Concerns” [2] .
- ↑ 1 2 Froese, Rainer, and Daniel Pauly, eds. Family Rajidae - Skates (Neopr.) . FishBase
- ↑ 1 2 3 4 5 Raja inornata . The IUCN Red List of Threatened Species .
- ↑ 1 2 3 4 Raja inornata in the FishBase database.
- ↑ Jordan DS & Gilbert S. H. Note on Raia inornata // Proceedings of the United States National Museum. - 1881. - Vol. 4, No. (194) . - P. 73-74.
- ↑ Eschmeyer, WN, Herald, ES and Hammann, H. A field guide to Pacific coast fishes of North America. - Boston, USA: Houghton Mifflin Company, 1983.
