''Huia'' is a group of

true frog True frogs is the common name for the frog family Ranidae. They have the widest distribution of any frog family. They are abundant throughout most of the world, occurring on all continents except Antarctica. The true frogs are present in North A ...

s found in

Southeast Asia Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical United Nations geoscheme for Asia#South-eastern Asia, south-eastern region of Asia, consistin ...

. Many are commonly known as "

torrent frog Torrent frogs are a number of unrelated frogs that prefer to inhabit small rapid-flowing mountain or hill streams with a lot of torrents. They are generally smallish neobatrachians with a greyish-brown and usually darkly mottled back, giving them e ...

s" after their favorite

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

- 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 Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

seems actually to be a

polyphyletic A polyphyletic group is an assemblage of organisms or other evolving elements that is of mixed evolutionary origin. The term is often applied to groups that share similar features known as homoplasies, which are explained as a result of converg ...

wastebin taxon Wastebasket taxon (also called a wastebin taxon, dustbin taxon or catch-all taxon) is a term used by some taxonomists to refer to a taxon that has the sole purpose of classifying organisms that do not fit anywhere else. They are typically defined ...

" and might contain only a fraction of the dozens of

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

placed here by some authors.Cai ''et al.'' (2007), Stuart (2008) Several

of '' Amolops'' and ''

Odorrana ''Odorrana'' (commonly known as the odorous frog) is a genus of true frogs (Ranidae) from East Asia and surrounding regions. Many of these frogs inhabit fast-flowing mountain streams, and they typically have a remarkably pointed snout, as evidenc ...

'' are highly convergent with ''Huia''. '' O. absita'' for example is highly similar in habitus to the completely

allopatric Allopatric speciation () – also referred to as geographic speciation, vicariant speciation, or its earlier name the dumbbell model – is a mode of speciation that occurs when biological populations become geographically isolated from ...

'' 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 In biology, adaptation has three related meanings. Firstly, it is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. Secondly, it is a state reached by the po ...

to habitat, the

tadpole A tadpole is the larval stage in the biological life cycle of an amphibian. Most tadpoles are fully aquatic, though some species of amphibians have tadpoles that are terrestrial. Tadpoles have some fish-like features that may not be found i ...

s of ''Amolops'', ''Huia'', ''Meristogenys'' as well as ''

Rana sauteri ''Rana sauteri'' is a species of true frog endemic to Taiwan. It inhabits low-altitude hill forests and the associated streams. It is an endangered species threatened by habitat loss due to agriculture and infrastructure development. Common nam ...

'' 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 ''Staurois'' is a small genus of minuscule true frogs. Most species in the genus are restricted to Borneo, but two species are from the Philippines.Arifin, U., D. T. Iskandar, D. P. Bickford, R. M. Brown, R. Meier, and S. N. Kutty. (2011). Phylo ...

'' from comparable

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

are sometimes placed in ''Huia'', including some originally placed into the genera ''

'' and ''Eburana'', which formed a

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

cluster; indeed these two genera are sometimes treated as

junior synonym The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. * In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linna ...

s 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 ''Meristogenys'' is a genus of true frogs from Borneo. Its tadpoles are adapted to fast-flowing mountain streams and easily recognizable by their divided upper lip with ribs on the outside.Stuart (2008) Taxonomy and systematics Its closest livin ...

''. Either the latter genus is included here, or ''Huia'' is restricted to the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

(the

Hole-in-the-head Frog The hole-in-the-head frog (''Huia cavitympanum'') is a species of frog in the family Ranidae. It is found on the island of Borneo. Its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical moist montane fores ...

, ''H. cavitympanum'') and what might be its closest living relatives (e.g. an undescribed species from

Sumatra Sumatra is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the sixth-largest island in the world at 473,481 km2 (182,812 mi.2), not including adjacent i ...

), 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''

s 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 Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...

uncertainties.Cai ''et al.'' (2007)

Species

The following species are recognised in the genus ''Huia'': * '' Huia cavitympanum'' –

* ''

Huia masonii The Javan torrent frog (''Huia masonii'') is a species of frog in the family Ranidae. It is endemic to Java, Indonesia. It is found in Mount Halimun Salak National Park, Ujung Kulon National Park, and Gunung Gede Pangrango National Park in West ...

'' –

Javan Torrent Frog The Javan torrent frog (''Huia masonii'') is a species of frog in the family Ranidae. It is endemic to Java, Indonesia. It is found in Mount Halimun Salak National Park, Ujung Kulon National Park, and Gunung Gede Pangrango National Park in We ...

* '' Huia melasma'' * '' Huia sumatrana'' – Sumatran Torrent Frog * ''

Huia modiglianii ''Wijayarana modiglianii'' is a species of frog in the family Ranidae. It is endemic to Sumatra (Indonesia). It was originally only known from two locations near Lake Toba, but is now known to be more widespread. The specific name ''modigliani ...

Footnotes

References

* (2007): Paraphyly of Chinese ''Amolops'' (Anura, Ranidae) and phylogenetic position of the rare Chinese frog, ''Amolops tormotus''. ''

Zootaxa ''Zootaxa'' is a peer-reviewed scientific mega journal for animal taxonomists. It is published by Magnolia Press (Auckland, New Zealand). The journal was established by Zhi-Qiang Zhang in 2001 and new issues are published multiple times a week. ...

'' 1531: 49–55
PDF abstract and first page text
* (2008): The phylogenetic problem of ''Huia'' (Amphibia: Ranidae). '' Mol. Phylogenet. Evol.'' 46(1): 49-60. (HTMl abstract) {{DEFAULTSORT:Huia (Genus) Amphibian genera