The tzucik bull-calf , or the marble blunt goby [1] ( lat. Proterorhinus marmoratus ) is a species of fish in the goby family (Gobiidae).
| Tsutsik bull |
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| Scientific classification |
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| No rank : | Bilateral symmetrical |
| Subfamily : | Benthophilinae |
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| International scientific name |
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Proterorhinus marmoratus ( Pallas , 1814) |
| Synonyms |
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- Gobius quadricapillus pallas , 1814
- Gobius blennioides Kessler, 1877
- Gobius macropterus Nordmann, 1840
- Gobius marmoratus Pallas, 1814
- Gobius marmoratus nasalis pontica Smitt, 1899
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| Security status |
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Least ConcernedIUCN 3.1 Least Concern : 18376 |
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For a certain period, this species of fish was noted as the only representative of the genus Proterorhinus . But it was revised as several cryptic species based on molecular analysis [2] . Now P. marmoratus is noted only for marine and brackish waters of the Black Sea basin [2] . All cases of registration of P. marmoratus in fresh waters are in fact attributed to the freshwater species Proterorhinus semilunaris .
The body and head are laterally compressed, the scales are rather large, cycloid [3] . The width of the head is much less than its height. The crown of the head, the nape of the neck, the upper edge of the gill covers, the bases of the pectoral fins, the belly and the back of the throat are covered with cycloid scales. Body color is brown or yellowish-gray with 4-5 dark stripes on the back, passing below the middle of the body into spots. The fins are usually striped. Length up to 12 cm. From the freshwater species Proterorhinus semilunaris close to it, it differs in the length of the head, which is 24–29% of the standard length [4] .
The species is widespread in the desalinated parts of the Black and Azov Seas, off the coast of Bulgaria, Georgia, Romania and Ukraine.
