Description
[This account was originally written for Pseudophilautus hallidayi, which was synonomized with Pseudophilautus fergusonianus by Ellepola et al. 2021]
Pseudophilautus hallidayi is a moderate-sized frog with snout-vent length (SVL) of 32.9 mm in males and 36.7 – 42.9 mm in females. The body is stout with a flat head that is dorsally convex. The snout-angle category is 5 or 6 (angle of snout 97º – 103º). Laterally, the snout is rounded. The edges of the canthal region are rounded, while the loreal region is concave. The interorbital space is flat and the internasal space sometimes appears flat or concave. The round tympanum is distinct. The vomerine teeth have a ridge; however, the holotype's left ridge is absent. There are 3 or 4 small teeth angled at about 70º relative to the body axis. Pseudophilautus hallidayi is lacks the following features: pineal ocellus, lingual papilla, cephalic ridges, tarsal tubercle, tarsal fold and co-ossified skin on skull. The supratympanic fold is distinct. The fingers have lateral dermal fringe. The ovular fingers and toes have discs. The palm and outer edge of the lower arm have prominent glandular warts. The palms have supernumerary tubercles; however, the pes region does not. The toes are webbed. On the tibio-tarsal articulation and pes's outer edge, there are distinct glandular warts. There are glandular warts located on the dorsum, upper flank, interorbital space, snout, and side of the head. In males, most of these areas listed have glandular warts, except the side of the head. Glandular warts are located on the dorsal side of the pes, shank, thigh, and forelimb. The throat and chest are smooth. The belly and thigh's underside are granular. Males have a granular chest and throat. Furthermore, males have nuptial pads and inner vocal slits (Meegaskumbura & Manamendra-Arachchi 2005).

In life, the dorsum and lateral head are brown and have symmetrical, dark-brown markings with white patches. The upper and lower flanks are brown and share a similar marking and patch coloration as the dorsum and lateral head. There are white markings on the dark brown inguinal zone. Dorsally, the limbs are brown with white dots and dark-brown crossbars. Posteriorly, the thigh is dark-brown. The coloration of the venter is pale brown. The webbing is dark-brown (Meegaskumbura & Manamendra-Arachchi 2005).

In preservative, the dorsal side of the species is brown with symmetrical dark-brown markings. The interorbital bar is dark brown. The brown upper and lower flank present with dark brown and white patches. The dark brown inguinal zone has white markings. There are dark-brown patches located on the tympanic and loreal region. The tympanum is a yellowish brown color with the outer rim being brown. The mid-tympanum region is dark brown. The brown upper lip has white patches. Dorsally, the limbs are brown with white dots and dark brown crossbars. The posterior aspect of the thigh is dark brown. The venter is a pale yellowish-brown color. The webbing is dark brown (Meegaskumbura & Manamendra-Arachchi 2005).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Sri Lanka

	View distribution map in BerkeleyMapper.
	View Bd and Bsal data (1 records).

This frog is found in central hills at elevations between 500 – 1400 m (Meegaskumbura & Manamendra-Arachchi 2005; Batuwita et al. 2019).

Life History, Abundance, Activity, and Special Behaviors
This frog is a habitat specialist usually observed perched on large boulders within closed-canopy habitats, often in proximity to large streams (Meegaskumbura & Manamendra-Arachchi 2005).

All frogs of this genus Pseudophilautus are known terrestrial direct developers (Bahir et al. 2005).

Comments
In a comprehensive phylogenetic analysis of the clade Pseudophilautus, Ellepola et al (2021) concluded that the molecular analysis grouped P. hallidayi and P. fergusonianus together as one species.

The species epithet of P. hallidayi had honored the 1994 International Director of the IUCN and SSC Task Force on Declining Amphibian Populations, Timothy Richard Halliday. His work consisted of research on amphibians and contributing to advancing the understanding of amphibian population decline worldwide (Meegaskumbura & Manamendra-Arachchi 2005).

Pseudophilautus hallidayi and P. cavirostris are both sister species. A 12S and 16S divergence of 7.9% and 15.7% cyctochrome-b divergence test was used to differentiate these two species (Meegaskumbura & Manamendra-Arachchi 2005).

References

Bahir, M. M., Meegaskumbura, M., Manamendra-Arachchi, K., Schneider, C. J., and Pethiyagoda, R. (2005). ''Reproduction and terrestrial direct development in Sri Lankan shrub frogs (Ranidae: Rhacophorinae: Philautus).'' The Raffles Bulletin of Zoology, 12, 339-350. [link]

Batuwita S, Udugampala S, DeSilva M, Diao J and Edirisinghe U. (2019). "A review of amphibian fauna of Sri Lanka: distribution, recent taxonomic changes and conservation." Journal of Animal Diversity, 1(2), 44-82. [link]

Ellepola G, Herath J, Manamendra-Arachchi K, Wijayathilaka N, Senevirathne G, Pethiyagoda R, Meegaskumbura M (2021) Molecular species delimitation of shrub frogs of the genus Pseudophilautus (Anura, Rhacophoridae). PLOS ONE 16(10): e0258594. [link]

Wickramasinghe, L.J.M., D.R. Vidanapathirana, M.D.G. Rajeev, S.C. Ariyarathne, A.W.A. Chanaka, L.L.D. Priyantha, I.N. Bandara & N. Wickramasinghe (2013). Eight new species of Pseudophilautus (Amphibia, Anura, Rhacophoridae) from Sripada World Heritage Site (Peak Wilderness), a local amphibian hotspot in Sri Lanka. Journal of Threatened Taxa 5(4): 3789–3920 [link]

Species Account Citation: AmphibiaWeb 2023 Pseudophilautus fergusonianus: Ferguson's Tree Frog <https://amphibiaweb.org/species/4510> University of California, Berkeley, CA, USA. Accessed Nov 22, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 22 Nov 2024.

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