''Taruga'' is a genus 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 ...

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 ...

to Sri Lanka. They are the only foam-nesting tree frogs in the Old World Tree frog family,

Rhacophoridae The Rhacophoridae are a family of frogs in tropical sub-Saharan Africa, South India and Sri Lanka, Japan, northeastern India to eastern China and Taiwan, south through the Philippines and Greater Sundas, and Sulawesi. They are commonly known as ...

. Genus ''Taruga'' was previously assigned to the genus ''Polypedates''. As presently understood, ''Taruga'' comprises three named species: ''T. fastigo'', ''T. eques'' and ''T. longinasus''. Hence two genera of foam-nesting rhacophorid tree frogs are present in Sri Lanka: (1) ''Polypedates'', with many species in India and Asia but just two in

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, ...

(''P. maculatus''— widely distributed in South Asia; and ''P. cruciger''— endemic to

, albeit widely distributed); and (2) ''Taruga'', the Sri Lankan endemic forms, whose three constituent species (''T. eques'', ''T. fastigo'' and ''T. longinasus'') each have restricted distributions mostly in the forested highlands. The best character to distinguish the adults of ''Taruga'' from

Polypedates ''Polypedates'' is a genus of frogs in the family (biology), family Rhacophoridae, the shrub frogs and Paleotropic tree frogs. They belong to subfamily Rhacophorinae. Members of this genus are collectively known as whipping frogs. They occur in ...

are a set of prominent cone-like projections around the vent. Furthermore, the supratympanic fold of Taruga is straighter than those in

. The snout of ''Taruga'' is very much acute than that of

. Considering

tadpoles A tadpole or polliwog (also spelled pollywog) 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-li ...

, the vent of Polypedates forms a tube between left leg and tail, and in ''Taruga'', there is no such tube, only an opening between leg and tail. There are also several more features of the mouth cavity, such as the number of projections on the tongue, shape of the tongue etc. that helps to distinguish ''Taruga'' from Polypedates. ''Taruga'' in

Sanskrit Sanskrit (; stem form ; nominal singular , ,) is a classical language belonging to the Indo-Aryan languages, Indo-Aryan branch of the Indo-European languages. It arose in northwest South Asia after its predecessor languages had Trans-cultural ...

(and early- Sinhala) means "tree climber". This name is very appropriate as the adults of these are tree inhabiting

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

, and rarely come to the ground. They often even lay their

eggs An egg is an organic vessel in which an embryo begins to develop. Egg, EGG or eggs may also refer to: Biology * Egg cell, the female reproductive cell (gamete) in oogamous organisms Food * Eggs as food Places * Egg, Austria * Egg, Switzerland ...

on vegetation overhanging water. All three frogs need shade in the form of a canopy to survive, and shallow and slow flowing streams or puddles to breed. The female of the species builds a foamy nest overhanging water where eggs develop for a few days, after which tadpoles fall into water where they undergo further development until

metamorphosis Metamorphosis is a biological process by which an animal physically develops including birth transformation or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and different ...

occurs. The juvenile frogs that emerge from water return to an arboreal life, on trees. Sri Lanka is now known to contain clade level endemicity despite many land-bridge connections with

India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...

. ''Taruga'' is yet another such deeply divergent clade. Following scientists contributed to this paper: Dr. Madhava Meegaskumbura (Dept. of Zoology,

University of Peradeniya The University of Peradeniya (, ) is a Public research university, public university in Sri Lanka, funded by the University Grants Commission of Sri Lanka, University Grants Commission. It is the largest university in Sri Lanka, which was origin ...

); Dr. Suyama Meegaskumbura (Dept. of Zoology,

), Mr. Gayan Bowatte (Dept. of Zoology,

), Prof. Christopher J. Schneider (

Boston University Boston University (BU) is a Private university, private research university in Boston, Massachusetts, United States. BU was founded in 1839 by a group of Boston Methodism, Methodists with its original campus in Newbury (town), Vermont, Newbur ...

, USA) and Prof. James Hanken (

Harvard University Harvard University is a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the History of the Puritans in North America, Puritan clergyma ...

, USA).

Species

There are three recognized species in this genus: *'' Taruga eques'' (Günther, 1858) *'' Taruga fastigo'' (Manamendra-Arachchi & Pethiyagoda, 2001) *'' Taruga longinasus'' (Ahl, 1927)

References

* Meegaskumbura, M. ''et al.''. 2010.

External links

* Taruga, a new tree-frog genus from Sri Lank

Taruga (frog), Frogs of Sri Lanka Rhacophoridae Amphibian genera {{Rhacophoridae-stub