Description
Diagnosis: A smaller species of the Litoria bicolor complex, with a maximum HB (head plus body length: measured from snout tip to distal end of urostyle) of 23.5 mm for adult males and 26.4 mm of adult females. Differs from L. eurynastes in having much smaller body size; differs from L. chloristona in having a narrower head (HL/HW 1.14 vs. 1.00 for L. chloristona), smaller eyes (EY/HB 0.10 vs. 0.13), and a larger tympanum (TY/HB 0.07 vs. 0.06 for L. chloristona); differs from L. lodesdema in having a larger body size (HB 23.5 vs. HB 22.0 for L. lodesdema), narrower head (HL/HW of 1.11 vs. 1.07 for L. lodesdema; wider internarial region (EN/IN of 1.01 vs. 1.07 for L. lodesdema), smaller eyes (EY/HB of 0.10 vs. 0.13 for L. lodesdema), and larger tympanum (TY/HB of 0.07 vs. 0.06 for L. lodesdema); and from L. bibonius by having shorter legs (TL/HB of 0.55 vs. 0.58 for L. bibonius), smaller eyes (EY/HB 0.12 vs. 0.11 for L. bibonius), and larger tympanum (TY/HB of 0.07 vs. 0.06 for L. bibonius).

Description: Adult males reach a maximum of 23.5 mm HB. Adult females measure up to 26.4 mm HB. Granular dorsal skin with coarse ventral skin, except for smooth throat. Head is longer in length than width. Large eyes. Pupils horizontal. Snout is obtusely pointed in dorsal view, and rounded in profile. Rounded and straight canthus rostralis. Tympanum small. Supratympanic skin fold obscures upper margin of tympanum. Fingers usually unwebbed; sometimes basal webbing to 1/3 webbing between Fingers III-IV. Finger discs larger than toe discs. Legs are long. Toes are almost completely webbed except for terminal phalanges which are usually free on Toes I, II and IV (occasionally, toe webbing may be complete, except for Toe IV). Males have a brown nuptial pad on the medial surface of Finger I (Menzies et al. 2008).

In life, green dorsum with a mid-dorsal bronze stripe. Narrow and dark canthal stripe that runs from the eye to the tympanum, then becomes indistinct, separating the green dorsum from the white ventrum. White upper lip with the white coloring extending below the eye and tympanum and eventually merging into the white venter. Dark brown groin and concealed surfaces of the thigh. Males have pale yellow throats (Menzies 2008).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Papua New Guinea

View distribution map in BerkeleyMapper.

Endemic to Papua New Guinea. Found in the woodlands of the Digul and Fly River plains extending from the coast northwards to Kiunga, where the woodlands transition to forest. Collected from Merauke in the west to Balimo in the east; it is not clear what the western limit of the range is. Occurs from 0-50 m asl. The region's climate is highly seasonal with the peak rainfall period between December and March (Menzies et al. 2008).

Life History, Abundance, Activity, and Special Behaviors
Breeds in temporary flooded areas and permanent waterways. Peak rainfall occurs from December to March. Breeding probably ceases during the dry season. Males called from vegetation overhanging the water (30 cm-3 m above the water surface). Two types of notes were emitted: short/fast and long/slow. Calls consisted of either note type but never both note types together. Short notes had a mean length of 0.078 seconds, made at 180 pulses/second; long notes had a mean length of 0.341 seconds, made at 39 pulses/second (Menzies et al. 2008).

Comments
The species' name is derived from the Latin words viridis, meaning "green" and ranula, a diminutive of rana or "frog" (Menzies et al. 2008).

References

Menzies, J. I., Richards, S. J. and Tyler, M. J. (2008). ''Systematics of the Australo-Papuan tree frogs known as Litoria bicolor (Anura : Hylidae) in the Papuan region.'' Australian Journal of Zoology, 56, 257-280.

Species Account Citation: AmphibiaWeb 2010 Litoria viranula <https://amphibiaweb.org/species/7387> University of California, Berkeley, CA, USA. Accessed Nov 21, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 21 Nov 2024.

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