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''Huia'' is a group of true frogs found in Southeast Asia. Many are commonly known as "torrent frogs" after their favorite habitat - small rapid-flowing mountain and hill streams -, but this name is used for many similar-looking frogs regardless of whether they are closely related. A seemingly less ambiguous name is huia frogs; however, the supposed genus seems actually to be a polyphyletic "wastebin taxon" and might contain only a fraction of the dozens of species placed here by some authors.〔Cai ''et al.'' (2007), Stuart (2008)〕 Several species of ''Amolops'' and ''Odorrana'' are highly convergent with ''Huia''. ''O. absita'' for example is highly similar in habitus to the completely allopatric ''H. masonii''. Though the latter might not be a member of ''Huia'' in the strictest sense, it is at least a very close relative.〔Stuart (2008)〕 In another incidence of convergent evolution yielding adaptation to habitat, the tadpoles of ''Amolops'', ''Huia'', ''Meristogenys'' as well as ''Rana sauteri'' have a raised and usually well-developed sucker on their belly. This is useful in keeping in place in rocky torrents, where these frogs grow up. But as ''Odorrana'' and ''Staurois'' from comparable habitat prove, this sucker is by no means a necessity and other means of adaptation to torrent habitat exist.〔 ==Systematics and taxonomy== Up to some 55 species are sometimes placed in ''Huia'', including some originally placed into the genera ''Odorrana'' and ''Eburana'', which formed a paraphyletic cluster; indeed these two genera are sometimes treated as junior synonyms of ''Huia''. The Long-snout Torrent Frog on the other hand – formerly ''Huia nasica'' – is now in ''Odorrana''. But many of the moves to ''Huia'' seem to be premature and it is better to treat ''Odorrana'' as valid, in a more comprehensive way and including ''Eburana'', than expanding ''Huia''.〔 For as it seems, even in the revised delimitation the genus is still paraphyletic with ''Meristogenys''. Either the latter genus is included here, or ''Huia'' is restricted to the type species (the Hole-in-the-head Frog, ''H. cavitympanum'') and what might be its closest living relatives (e.g. an undescribed species from Sumatra), or some species of ''Huia'' - e.g. the Sumatran Torrent Frog (''H. sumatrana'') - are split off again. The former alternatives seem to be more advisable as long as the interrelationships of ''Huia'' and ''Meristogenys'' species as well as the closely related ''Clinotarsus'' are as badly resolved as they are at present. ''Meristogenys'' tadpoles are furthermore characterized by a split and ridged upper lip not found in the Hole-in-the-head Frog, indicating that the genera ought to be kept separate.〔 New species are being discovered regularly, exacerbating the taxonomic uncertainties.〔Cai ''et al.'' (2007)〕 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「Huia (frog)」の詳細全文を読む スポンサード リンク
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