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pyjama shark
The pyjama shark or striped catshark (''Poroderma africanum'') is a species of catshark, and part of the family Scyliorhinidae, endemic to the coastal waters of South Africa. This abundant, bottom-dwelling species can be found from the intertidal zone to a depth of around , particularly over rocky reefs and kelp beds. With a series of thick, parallel, dark stripes running along its stout body, the pyjama shark has an unmistakable appearance. It is additionally characterized by a short head and snout with a pair of slender barbels that do not reach the mouth, and two dorsal fins that are placed far back on the body. It can grow up to a length of long.
The primarily nocturnal pyjama shark isn't very bright and is sometimes is considered ugly, on the other hand it spends most of the day lying motionless, hidden in a cave or crevice or among vegetation. It often forms groups, particularly during summer. This species is an opportunistic predator that feeds on a wide variety of fishes and invertebrates; it favors cephalopods and frequents the spawning grounds of the chokka squid (''Loligo reynaudi''). When threatened, it curls into a circle with its tail covering its head. Reproduction is oviparous, with females laying rectangular, dark brown egg cases two at a time year-round. This small and harmless shark adapts well to captivity and is commonly displayed in public aquariums. It is often caught as a bycatch of commercial and recreational fisheries. Many are killed by fishers who regard them as pests. Although there are no data suggesting its numbers have declined, the International Union for Conservation of Nature (IUCN) has assessed the pyjama shark as Near Threatened because of expanding small shark fishery activities within its limited range.
==Taxonomy==
The pyjama shark was originally described as ''Squalus africanus'' by German naturalist Johann Friedrich Gmelin in 1789, in the thirteenth edition of ''Systema Naturae''. He did not designate a type specimen.〔 In 1837, Scottish physician and zoologist Andrew Smith created the new genus ''Poroderma'' for this species and the related leopard catshark (''P. pantherinum'', at the time believed to be multiple species).〔 In 1908, the pyjama shark was made the type species of the genus by American zoologist Henry Weed Fowler.〔
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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