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Family : RHACOPHORIDAE
Species : Polypedates discantus
Size (snout to vent) :
Female to 67 mm,  Male to 57 mm
(Rujiwaran et al, 2013).

Play calls ►   
[composite audio of two of the call types]


Polypedates discantus (Malayan Slender Tree Frog) was described as a new species in 2013 from specimens taken in Songkhla province, southern Thailand (Rujirawan et al, 2013). Formerly it was treated as a form of Polypedates leucomystax (Four-lined Tree Frog). 

The range of this somewhat elusive frog appears to be limited to parts of southern Thailand and Peninsular Malaysia; it has yet to be found in Singapore, despite searches by enthusiasts and researchers.

When present in the same general area, P. discantus often frequents the same breeding sites as P. leucomystax, a common and highly adaptable species.

In the field, the easiest way to separate P. discantus from P. leucomystax is by its calls. P. leucomystax emits a loud single duck-like 'quack' call. P. discantus however has a range of quieter calls including one-note, two-note and three-note clicking sounds, as well as a 'staccato' call of around 10 or more separate pulses (Rujirawan et al, 2013).

Close observation of the tibio-tarsal articulation (i.e. near the 'ankle') of P. discantus will reveal a raised tubercle, which P. leucomystax lacks (Rujirawan et al, 2013).

Documented here is a grassy, roadside pool, found at an elevation of 320 metres in the state of Selangor, Peninsular Malaysia; this small pond is partly formed by the wheel ruts of passing vehicles. Around 10 or so frogs were calling after dusk from the vegetated embankment next to this pool on two successive nights, comprising both P. discantus and P. leucomystax in roughly equal numbers.

Three examples of P. discantus are shown here; their colour ranges from yellowish to light brown, and their patterning includes faint dorsolateral stripes (Figure 1) and a plain dorsum with dark spots (Figure 2). The frog in Figure 1 clearly possesses the raised tubercle on its tibio-tarsal articulation. 

The frog in Figure 1 was heard (and seen) to emit a 2-note call. Also recorded at this site were examples of the 'staccato' call. 

It was noted that P. discantus kept well hidden amongst tangled vegetation, unlike P. leucomystax which was more bold in its habits and would often perch on exposed twigs.

A search was made for bubble nests and larger, female frogs of both P. discantus and P. leucomystax but none were present. A search for tadpoles found a single tadpole of P. leucomystax. No tadpoles of P. discantus were found (tadpoles of this species do not appear to be formally described).

Other frogs at this degraded site included Phrynoidis asper (River Toad), and Hylarana (Abavorana) luctuosa (Mahogany Frog); the latter was heard calling from the embankment, and three tadpoles were found of this ranid.