Urolophus circularis (lat.) Is a rather rare and poorly studied species of the genus Urolophus of the family of short-tailed stingrays of the order of tailed-like . It is endemic to the coastal subtropical waters of the southwest coast of Australia. It occurs at a depth of up to 120 m. The pectoral fins of these slopes form an oval disk. The color is very colorful. The dorsal surface of the disc is covered with numerous small bright spots and circles scattered on a gray-blue background. Between the nostrils there is a rectangular fold of skin. The posterior edges of the nostrils form wide lobes. The short tail ends with a lanceolate caudal fin. In the middle part of the caudal stem, behind a large dorsal fin, there is a serrated spike. The maximum recorded length is 60 cm. Propagated by oviparous . Not an object of target fishing. By-catch occurs in commercial fishing [1] [2] .
| Urolophus circularis |
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| No rank : | Bilateral symmetrical |
| Family: | Short-tailed Stingers |
| View: | Urolophus circularis |
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Urolophus circularis = McKay , 1966 |
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Least ConcernedIUCN 3.1 Least Concern : 60089 |
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The species was first scientifically described by the Australian ichthyologist Roland Mackay in 1966 on the basis of an individual caught off the coast of Fremantle , Western Australia [3] . Species epithet comes from the word lat. circularis - “circle” and is connected by the disk shape of these rays [4] .
Urolophus circularis live in a limited area off the southwest coast of Australia between Esperance and Rottnest Island [1] . These fish are found on rocky and coral reefs, as well as in thickets of algae from the coast to a depth of 120 m [1] [5] [5] .
The wide pectoral fins of these slopes merge with the head and form an oval disk, the width is almost equal to the length. the front edge of the disk is slightly curved, the pointed fleshy snout forms an obtuse angle and protrudes beyond the edges of the disk. Behind large eyes are comma- shaped sprays with rounded posterior edges. Between the nostrils lies a short leather flap in the form of a "skirt" whose lower edge forms the lobes. The large mouth contains small teeth with oval bases. At the bottom of the oral cavity there are 10 finger-shaped processes, the same processes cover the lower jaw. On the ventral side of the disk there are 5 pairs of short gill slits . Small ventral fins rounded [5] [6] .
The length of the short tail is 2/3 of the length of the disk. It has an oval cross section, flattened. Lateral folds of skin are absent. The tail narrows and turns into a long and low lanceolate caudal fin. On the dorsal surface of the tail in the central part behind the large dorsal fin, a serrated spine is located. The skin is devoid of scales . The maximum recorded length is 60 cm. The dorsal surface of the disk is covered with numerous small bright spots and circles scattered on a brownish-red background. In the center of the disk is a ring formed by black spots with a light border. The dorsal fin and the edge of the caudal fin are brownish. The ventral surface is light; toward the tail, it acquires a brown hue [5] .
Like other caudate-like, these rays are reproduced by ovipositor production. Litter is probably not numerous. Males reach puberty with a length of 53 cm [1] .
These stingrays are not targeted, although their meat is edible. As a by- catch, they are occasionally found in commercial fisheries. The International Union for Conservation of Nature has assigned this species a conservation status of “Least Concerns” [1] .
