''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 carnivorous group of short-bodied, tailless amphibians composing the order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-frog" ''Triadobatrachus'' is ...

. It used to be placed in the large frog

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Ranidae but a phylogenetic study was undertaken using DNA sequences and it is now included in the family

Dicroglossidae The frog family Dicroglossidae occurs in tropical and subtropical regions of Asia and Africa, with most genera and species being found in Asia. The common name of the family is fork-tongued frogs. The Dicroglossidae were previously considered to ...

. It is

endemic Endemism is the state of a species being found 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 found else ...

to Sri Lanka where its natural

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 ...

s are subtropical or tropical moist lowland

forest A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...

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 fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial ...

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of w ...

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 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 ...

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, ''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