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blind shark
The blind shark (''Brachaelurus waddi'') is one of two species of carpet sharks in the family Brachaeluridae, along with the bluegrey carpetshark (''Brachaelurus colcloughi''). Found along the coast of eastern Australia, this nocturnal, bottom-dwelling species is common in rocky areas and seagrass beds from the intertidal zone to a depth of . It often roams in tidal pools where it may be trapped by the receding tide, and can survive for an extended period out of water. The blind shark is not actually blind; its common name came from its habit of closing its eyes when taken out of the water.
Maturing at under long, the blind shark has a stocky, grayish to brownish body with white flecks and darker bands that fade with age. Its head is wide, flattened, and blunt, with small eyes on top and a pair of long barbels underneath. It has large pectoral fins, two nearly equal-sized dorsal fins placed far back on the body, and an anal fin placed close to the caudal fin. The blind shark feeds primarily on small invertebrates and bony fishes. It is aplacental viviparous with females bearing litters of 7–8 pups in the summer. This small shark adapts readily to being kept in captivity. It is not valued by either commercial or recreational fishers, and its hardiness means that incidentally caught individuals are likely to be returned to the water alive. In the absence of substantial threats to its population, the International Union for Conservation of Nature has assessed it as of Least Concern.
==Taxonomy and phylogeny==
German naturalists Marcus Elieser Bloch and Johann Gottlob Schneider originally described the blind shark as ''Squalus waddi'', in their 1801 ''Systema Ichthyologiae''. However, there is uncertainty over whether their account was referring to this species or the brownbanded bamboo shark (''Chiloscyllium punctatum''), as it was based on a painting by John Latham that could not be located by subsequent authors. In 1907, James Douglas Ogilby coined the genus ''Brachaelurus'' for this species, from the Greek ''brachys'' meaning "short", and ''ailouros'' meaning "cat".〔 In 1973, Leonard Compagno placed it and the bluegrey carpetshark in their own family.〔 This shark may also be referred to as the brown catshark or dusky dogfish.〔
Various phylogenetic studies, based on morphology, have concluded that the blind shark lineage represents the sister taxon to the wobbegongs.〔 Blind shark fossils have been found in Late Cretaceous period (99.6–65.5 Ma) deposits from Europe, as well as in Pliocene epoch (5.3–2.6 Ma) deposits from Chile and Peru. A number of other ''Brachaelurus'' species are also known from the fossil record.〔
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
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