Description
Pseudophilautus stuarti is a moderate size frog with snout vent length of 24.2 – 25.3 mm in males and 32.45 mm in females. Head dorsally flat. Snout-angle of 105° – 107°); snout rounded in lateral aspect. Canthal edges sharp. Loreal region concave. Interorbital and internasal spaces flat. Tympanum distinct, vertically orientated, crescentic. Vomerine ridge absent. Pineal ocellus, lingual papilla, cephalic ridges, calcar, and co-ossified skin on skull absent. Supratympanic fold prominent. Lateral dermal fringe absent on fingers. Supernumerary tubercles present on both palm and on pes. Toes webbed. Tarsal folds absent. Snout, interorbital space, and both anterior and posterior dorsum with horny spinules; side of head, both upper and lower flanks smooth. Dorsal part of forelimb, thigh, shank and pes smooth. Throat, chest, belly and underside of thigh granular. Females lack horny spinules on dorsum. Inner vocal slits present, nuptial pad absent in males (Meegaskumbura & Manamendra-Arachchi, 2005).

In life, the dorsum is light green with ashy green, ashy yellow or black dots. Tympanum, tympanic region and loreal region are green. Upper, lower lips, supratympanic fold and canthal edges are yellow. Limbs and digits dorsally yellow and ventrally "ashy yellow". Mid-flank, chin and chest are yellow. Abdomen and area around vent are "ashy flesh colour". Granules on abdomen are white. Anterior and posterior thigh is brown (Meegaskumbura & Manamendra-Arachchi 2005).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Sri Lanka

View distribution map in BerkeleyMapper.

This species is known from only two localities at the southern end of the Knuckles mountain range of central Sri Lanka: Cobett’s Gap and Bambarella Peak at elevations of 1245m (Meegaskumbura & Manamendra-Arachchi 2005).

Life History, Abundance, Activity, and Special Behaviors
This species is primarily nocturnal, but can also be found during the day in areas that are in the shade. At night, they are normally found sitting on shrubs and bushes that are about 1-meter high. In most cases it is seen in cloud forest with good canopy cover. Males will call from shrubs 2-3 m above ground (Meegaskumbura & Manamendra-Arachchi 2005).

Larva
All frogs of this genus are direct developers (Meegaskumbura & Manamendra-Arachchi 2005).

Possible reasons for amphibian decline

General habitat alteration and loss
Habitat modification from deforestation, or logging related activities
Intensified agriculture or grazing
Habitat fragmentation

Comments
The species authority is: Meegaskumbura & Manamendra-Arachchi (2005).

This species is named after Dr. Simon Nicolas Stuart, former Acting Director General of IUCN (2000-2001). He is known for establishing international conservation projects through worldwide biodiversity studies especially on threatened species. He also led the development of the new IUCN Red List categories as head of the Species Survival Commission (1991-2000) (Meegaskumbura & Manamendra-Arachchi 2005).

The sister species of Pseudophilautus stuarti is Pseudophilautus viridis. These two species have a mtDNA sequence divergence of 6.6% which separates them from each other. P. viridis occurs on the peaks of the Central Hills at above 1,000 m while P. stuarti is restricted to the Knuckles Mountain Range at about 1,245 m. They are separated from each other by the Mahaweli River valley at about 500 m at Kandy (Meegaskumbura & Manamendra-Arachchi 2005).

References

Meegaskumbura M. & Manamendra-Arachchi K. (2005). ''Description of eight new species of shrub frogs (Ranidae: Rhacophorinae: Philautus) from Sri Lanka.'' Raffles Bulletin Zoology Supplemental, 12, 305-338. [link]

Species Account Citation: AmphibiaWeb 2022 Pseudophilautus stuarti: Stuart's Shrub Frog <https://amphibiaweb.org/species/6519> University of California, Berkeley, CA, USA. Accessed Nov 12, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 12 Nov 2024.

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