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The Philippines spurdog (''Squalus montalbani''), also known as the Indonesian greeneye spurdog is a relatively large species of dogfish shark native to waters off the coast of Australia, the Philippines, and Indonesia. The species was identified in 1912 from a specimen caught off the coast of Luzon Island, and has been both bycatch and a targeted species in fisheries since. Its taxonomy is complex, having been renamed in 1931, being misidentified as a type of shortspine spurdog, then being revived as a species in 2007. It is classified as vulnerable by the International Union for Conservation of Nature (IUCN) due to past and present threats from fisheries. It is morphologically similar to several other species, which makes identification difficult. The species is identified as a member of the mitsukurii group, a species complex〔 The similarity to other species has posed problems in identifying trends in the species, and thus, in its conservation.〔 == Biology, anatomy, and appearance == ''S. montalbani'' is relatively large, in comparison to other dogfish sharks. Females, with a maximum total length of are generally larger than males, which have a maximum total length of . The spines on the dorsal fin are low, like others in the mitsukrii species complex. Coloration patterns are similar to others in the mitsukrii group: The dorsal surface is a light grey, and the ventral surface is white.〔 The caudal bar is a dark bar found on the caudal fin of some species, including some sharks. Like other sharks in the mitsukurii group, the Philippines spurdog has a caudal bar which is dark and almost upright, however the caudal bar extends further in ''S. montalbani'' than ''S. mitsukurii'', allowing visual differentiation of the species.〔 An additional coloration pattern distinguishes the two species: a dark blotch on the upper lobe of the caudal fin appears in both ''S. montalbani'' and ''S. mitsukurii'', however the placement and shape differs.〔 Like most sharks, the species is yolk-sac viviparous.〔 The species has been observed with litter sizes of 4-16 pups, with pups developing a yolk sack in utero. Diet is described in White et al. 2006〔 "primarily of small fishes, cephalopods and crustaceans," which is repeated by the IUCN.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Squalus montalbani」の詳細全文を読む スポンサード リンク
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