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dark shyshark
The dark shyshark or pretty Happy (''Haploblepharus pictus'') is a species of catshark, belonging to the family Scyliorhinidae, endemic to the temperate waters off southern Namibia and western South Africa. It is benthic in nature and inhabits shallow, inshore waters and favors rocky reefs and kelp forests. Growing to long, this small, stocky shark has a wide, flattened head with a rounded snout and a large flap of skin extending from before the nostrils to the mouth. Its dorsal coloration is extremely variable and may feature black-edged orange to blackish saddles and/or white spots on a light brown to nearly black background.
When threatened, the dark shyshark curls into a ring with its tail covering its eyes, hence the name "shyshark". It preys mainly on small crustaceans, bony fishes, and molluscs. Reproduction is oviparous and proceeds throughout the year. Females lay two egg cases at a time, which hatch after 6–10 months. This harmless species is of little commercial significance due to its small size. It is frequently caught by recreational fishers and persecuted as a pest. The International Union for Conservation of Nature (IUCN) has listed the dark shyshark under Least Concern, as it is common and does not appear to be substantially threatened by fishing or habitat degradation.
==Taxonomy and phylogeny==
German physicians and biologists Johannes Peter Müller and Friedrich Gustav Jakob Henle originally described the dark shyshark in their 1838–41 ''Systematische Beschreibung der Plagiostomen'', based on five specimens caught off the Cape of Good Hope and deposited in the Rijksmuseum van Natuurlijke Historie in Leiden, The Netherlands. Because of the shark's ornate coloration, they gave it the specific epithet ''pictum'' from the Latin for "painted".〔〔 Originally placed in the now-obsolete genus ''Scyllium'', subsequent authors moved this species to the genus ''Haploblepharus'', coined by American zoologist Samuel Garman in 1913.〔
The dark shyshark was often regarded to be the same as the puffadder shyshark (''H. edwardsii'') until 1975, with the publication of A.J. Bass, Jeanette D'Aubrey, and Nat Kistnasamy's review of southern African sharks. It continues to be confused for the other three shyshark species because of its extremely variable coloration.〔〔 The common name "pretty Happy" ("Happy" refers to the genus name ''Haploblepharus'') was recently introduced to the public as an easily remembered alternative to the colloquial names "shyshark" and "doughnut", which can apply to several species and have confounded research efforts.〔〔 Brett Human's 2006 phylogenetic analysis, based on three mitochondrial DNA genes, found that the dark shyshark and the brown shyshark (''H. fuscus'') are sister species, and that the two make up the more derived clade within the genus.〔
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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