The Dicroglossidae have previously been grouped within the Ranidae. The phylogenetic relationships and often the taxonomic recognition of species are controversial. Nothing contained herein shall be construed as conferring by implication or otherwise any license or right under any trademark of AMNH. Frogs of the family Dicroglossidae were previously placed under Family Ranidae as the subfamily Dicroglossinae. By using endogenous retroviruses as genetic markers, we found that sheep differentiated on the basis of their "retrotype" and morphological traits dispersed across Eurasia and Africa via separate migratory episodes. These molecular markers appear to be adequate for the identification of species. We subjected the molecular data molecular to phylogenetic analyses. In the resulting trees, topotypic F.
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Order: Anura
Family: Dicroglossidae
The streamlined frogs (those in the genus Nannophrys) diverged from all other species nearly 55 million years ago, so in evolutionary terms a chinchilla and a porcupine are more similar to one another than streamlined frogs are to their nearest relatives. This genus is endemic to Sri Lanka, and with only three close relatives, the Ceylon streamlined frog (N. ceylonensis), the marbled streamlined frog (N. marmorata) and the recently described N. naeyakai, Gunther’s streamlined frog represented a high level of genetic diversity. Two out of the three of the extant species are threatened on the IUCN Red List of Threatened Species - the Ceylon streamlined frog is listed as Vulnerable and the marbled streamlined frog as Critically Endangered - so there is a risk that, unless conservation measures are taken, this whole genus may be lost in the relatively near future. The final species in the group, N. naeyakai, was only described in 2007 so has not yet been assessed by the IUCN, however it is unlikely to have a large distribution or large population given that it has remained unknown until recently.
Gunther’s streamlined frog was less toad-like in appearance than other streamlined frogs. Adults grew to less than 3 cm in length, had a rounded snout, horizontal pupils and slender toes with virtually no webbing. The species had a warty back, and warts on the upper surfaces of the head and legs, with a smooth underside.
Gunther’s streamlined frog is only known from a few specimens collected more than 100 years ago, so very little is known about the species’ ecology and habitat preferences. It is assumed that the species bred near streams on the surfaces of wet rocks, like other streamlined frogs; tadpoles of the closely related Ceylon streamlined frog have been found in sheets of water which spread over low ground during the monsoon season from May to September.
The other streamlined frogs are confined to the southern region of Sri Lanka where the dominant vegetation types are lowland wet evergreen forest and wet fernlands and grasslands, and there is a high rainfall of up to 650 cm a year, habitat preferences which Gunther’s streamlined frog may have shared.
Gunther’s streamlined frog is only known from a few specimens collected more than 100 years ago, so very little is known about the species’ ecology and habitat preferences. It is assumed that the species bred near streams on the surfaces of wet rocks, like other streamlined frogs; tadpoles of the closely related Ceylon streamlined frog have been found in sheets of water which spread over low ground during the monsoon season from May to September.
The other streamlined frogs are confined to the southern region of Sri Lanka where the dominant vegetation types are lowland wet evergreen forest and wet fernlands and grasslands, and there is a high rainfall of up to 650 cm a year, habitat preferences which Gunther’s streamlined frog may have shared.
As very little is known about Gunther’s streamlined frog it is difficult to assess what factors drove the species to extinction. However, the natural habitat of Sri Lanka has suffered a great deal of degradation and loss, with only small patches of forest remaining in a landscape which is now dominated by agricultural plantations and rice paddies. This habitat loss and pollution are both considered major threats to two of the extant species in the genus and may also be to blame for the loss of Gunther’s streamlined frog.
AmphibiaWeb: Information on amphibian biology and conservation [web application]. 2006. Berkeley, California: AmphibiaWeb. Available: amphibiaweb. Accessed: 08 December 2006.
Brooks, T. M., R. A. Mittermeier, C. G. Mittermeier, G. A. B. da Fonseca, A. B. Rylands, W. R. Konstant, P. Flick, J. Pilgrom, S. Oldfield, G. Magin & C. Hilton-Taylor. 2002. Habitat loss and extinction on the hotspots of biodiversity. Conservation Biology. 16 (4): 909-923.
Clarke, B. T. 1983. A morphological re-examination of the frog genus Nannophrys (Anura: Ranidae) with comments on its biology, distribution and relationships. Zoological Journal of the Linnean Society 19: 377-398.
Frost, Darrel R. 2006. Amphibian Species of the World: an Online Reference. Version 4 (17 August 2006). Electronic Database accessible at:. American Museum of Natural History, New York, USA.
IUCN, Conservation International and NatureServe. 2006. Global Amphibian Assessment. Global Amphibian Assessment. Accessed on 08 December 2006.
Kirtisinghe, P. 1957. The Amphibia of Ceylon. Published by the Author, Colombo, Ceylon.
Suranjan Fernando, S., L. J. Mendis Wickramasingha & R. K. Rodirigo. 2007. A new species of endemic frog belonging to genus Nannophrys Gunther, 1869 (Anura: Dicroglossinae) from Sri Lanka. Zootaxa 1403: 55-68.
Brooks, T. M., R. A. Mittermeier, C. G. Mittermeier, G. A. B. da Fonseca, A. B. Rylands, W. R. Konstant, P. Flick, J. Pilgrom, S. Oldfield, G. Magin & C. Hilton-Taylor. 2002. Habitat loss and extinction on the hotspots of biodiversity. Conservation Biology. 16 (4): 909-923.
Clarke, B. T. 1983. A morphological re-examination of the frog genus Nannophrys (Anura: Ranidae) with comments on its biology, distribution and relationships. Zoological Journal of the Linnean Society 19: 377-398.
Frost, Darrel R. 2006. Amphibian Species of the World: an Online Reference. Version 4 (17 August 2006). Electronic Database accessible at:
IUCN, Conservation International and NatureServe. 2006. Global Amphibian Assessment. Global Amphibian Assessment. Accessed on 08 December 2006.
Kirtisinghe, P. 1957. The Amphibia of Ceylon. Published by the Author, Colombo, Ceylon.
Suranjan Fernando, S., L. J. Mendis Wickramasingha & R. K. Rodirigo. 2007. A new species of endemic frog belonging to genus Nannophrys Gunther, 1869 (Anura: Dicroglossinae) from Sri Lanka. Zootaxa 1403: 55-68.
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