''Nannophrys ceylonensis'', commonly known as the Sri Lanka rock frog or the Ceylon streamlined frog, is a species of

frog A frog is any member of a diverse and largely semiaquatic group of short-bodied, tailless amphibian vertebrates composing the order (biology), order Anura (coming from the Ancient Greek , literally 'without tail'). Frog species with rough ski ...

. It used to be placed in the large frog

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Ranidae but a phylogenetic study was undertaken using

DNA Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...

sequences and it is now included in the family Dicroglossidae. It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

Sri Lanka Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka, also known historically as Ceylon, is an island country in South Asia. It lies in the Indian Ocean, southwest of the Bay of Bengal, separated from the Indian subcontinent, ...

where its natural

habitat In ecology, habitat refers to the array of resources, 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 manifestation of its ...

s are subtropical or tropical moist lowland

forest A forest is an ecosystem characterized by a dense ecological community, community of trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, ...

s, subtropical or tropical moist

montane forest Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures lapse rate, fall as elevation increases, causing the ecosystem to stratify. This stratification is ...

river A river is a natural stream of fresh water that flows on land or inside Subterranean river, caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of ...

s and streams.

Description

Female Sri Lanka rock frogs grow to a length of about while males grow to . The colour is olive green or yellowish-brown, mottled with brown patches. The legs have transverse bars of brown. When sitting on alga covered rocks it is well camouflaged.

Distribution and habitat

The Sri Lanka rock frog is endemic to south, central and western Sri Lanka where it is found in wet tropical forests at altitudes of up to above sea level. It is a largely aquatic species and occurs in fast flowing mountain streams, under boulders and on wet rocks beside waterfalls. It is also found on land in disturbed areas where there are suitable breeding locations such as wet seeps. The

tadpole A tadpole or polliwog (also spelled pollywog) is the Larva, larval stage in the biological life cycle of an amphibian. Most tadpoles are fully Aquatic animal, aquatic, though some species of amphibians have tadpoles that are terrestrial animal, ...

s are semi-terrestrial and are sometimes found on wet rocks beside torrents.

Biology

The female Sri Lanka rock frog typically spawns a cluster of eggs in a crevice in the splash zone of a mountain stream. The male frog guards the eggs in several nests and ensures that they are kept moist while the female plays no further part in parental care. The eggs hatch into tadpoles that forage for small invertebrates on the surface of the rocks near their nest.

Status

In the

IUCN Red List of Threatened Species The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological spe ...

, ''Nannophrys ceylonensis'' is listed as Vulnerable. This is because numbers seem to be declining and it has several disjunct populations, the total area of its range being less than 2,000 square kilometres (770 square miles). The streams in which it lives and breeds are subject to pollution by agrochemicals and the volume of water is reduced during periods of drought.

References

{{Taxonbar, from=Q2245266 Nannophrys Amphibians described in 1869 Taxa named by Albert Günther Frogs of Sri Lanka Endemic fauna of Sri Lanka Taxonomy articles created by Polbot