Brazilian bull ( lat. Rhinoptera brasiliensis ) [1] is a type of cartilaginous fish of the genus Bycherly of the family of eagle rays of the order detachment of the tail-like supernova of the slopes . These stingrays live in the tropical waters of the southwestern Atlantic Ocean . The maximum recorded width of the disk is 102 cm. The pectoral fins of these skates grow together with the head, forming a diamond-shaped disk, the width of which exceeds the length. The snout is massive, flat, the front edge is almost straight with a notch in the middle. Thin tail is longer than the disc.
| Brazilian cherries |
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| Scientific classification |
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| No rank : | Bilateral symmetric |
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| International Scientific Name |
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Rhinoptera brasiliensis JP Müller , 1836 |
| Security status |
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Endangered speciesIUCN 3.1 Endangered : 44595 |
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Like the other caudal-shaped, Brazilian bycats reproduce by egg production . Embryos develop in the womb, feeding on the yolk and histotrophs . These skates are of minor interest for commercial fishing [2] [3] .
Content
The species was first scientifically described in 1836 [4] . In 1953, a detailed description was made of Brazilian and East American bycherylov based on materials obtained from Brazil, but the authors noted that these forms are probably not different species [5] . The name Rhinoptera brasiliensis has not been used for a long time. However, in 1997, the presence of both species in the waters of Rio de Janeiro was confirmed and all three individuals of the genus Rhinoptera caught in the 1980s off the coast of Rio Grande do Sul turned out to be Brazilian bycherly. Brazilian bicheryla differs from the East American size of newborns. In Brazilian bycherylov, the mouth is wider and the distance between the nostrils and between the sprigits is wider [3] .
Brazilian bycheryly are endemics of the coast between Rio de Janeiro and Rio Grande do Sul, a length of about 1,800 km. In the summer, they migrate to the south, breaking up to 700 km and are found in shallow waters less than 20 m deep in the waters of Rio Grande do Sul . The water temperature at the bottom in these places in January is about 22 ° C, and in August it drops to 13 ° C. Probably, seasonal migrations are due to temperature changes. Brazilian bichers prefer sandy bottom [3] .
Externally, the Brazilian bycheryla very similar to the East American bycherylov. Their pectoral fins, the base of which is located behind the eyes, grow together with the head, forming a diamond-shaped flat disk, the width of which exceeds the length, and the edges of the fins have the shape of pointed (“wings”). The head is wide with eyes spaced at the sides and two pineal lobes on the snout. These rays differ from other caudal-like protrusions of the anterior contour of the cartilaginous skull and the sub-fins with two lobes. Sprigulae are located behind the eyes. The whipped tail is longer than the disc. On the ventral surface of the disk there are 5 pairs of gill slits , mouth and nostrils. Teeth form a flat, rubbing surface. On the upper jaw there are 9 dentitions [5] . The maximum recorded width of the disk is 102 cm [3] .
Like other caucula-like brazilian bulls, they belong to the oviparous fish. Embryos develop in the womb, feeding on the yolk and histotrophs . Probably only 1 newborn in litter. On average, the disc width for males varies between 78–91 cm, and for females 77–102. A capture of a pregnant female with a disk 102 cm wide was recorded. The disc width of newborn skates is 43–48 cm. The diet consists mainly of mollusks [3] .
Brazilian cattle are of minor interest for commercial fisheries. Caught as by-catch. Intensive fisheries are conducted in the area. The International Union for Conservation of Nature assigned this species the Protecting Statute “The Endangered” [3] .
- ↑ Reshetnikov Yu. S. , Kotlyar A. N. , Russ T. S. , Shatunovsky M. I. Pyatiazychny dictionary of animal names. Fish. Latin, Russian, English, German, French. / edited by Acad. V.E. Sokolova . - M .: Rus. laz., 1989. - p. 46. - 12 500 copies. - ISBN 5-200-00237-0 .
- ↑ Brazilian bycheryl (Eng.) In the database FishBase .
- ↑ 1 2 3 4 5 6 Rhinoptera brasiliensis (English) . The IUCN Red List of Threatened Species .
- ↑ Müller, A. (1999) Ichthyofaunen aus dem atlantischen Tertiär der USA. Leipziger Geowissenschaften, 9-10: 1-360, 69 fig., 6 tabl., 17 pl
- ↑ 1 2 Bigelow, HB and Schroeder WC Sawfishes, guitarfishes, skates and rays = In Tee-Van J. et al. (eds.) Fishes of western Atlantic. Part two. - New Haven, Sears Found. Mar. Res., Yale Univ., 1953. - P. 1-514.
- Brazilian species (English) in the World Register of Marine Species .
