Family : RANIDAE
Species : Sylvirana guentheri
Size (snout to vent) : typically up to 8 cm, sometimes larger.
Gόnther's Frog is a medium
to large sized ranid, or typical frog. In its natural habitat it occurs in
swamps, marshes and streams, but it has adapted well to rice fields and
Another name for this frog is 'Brown and Tan Amoy Frog', after the coastal
city in China from where it was first described (the city is now called
It is smooth skinned, and has a well developed 'dorsolateral' ridge on each
side which separates the upper flank from the back. Its front feet are
webbed and its hind feet are strongly webbed.
Its colouration comprises various shades of brown. Its back is medium brown,
and its flanks are dark brown immediately below the dorsolateral ridges and
mottled pale brown on the lower flanks. Its underside is white, and its hind
legs possess thick dark brown bars.
Its call is a loud double croak, typically emitted whilst floating in the
water. This can easily be heard late afternoon to early evening.
Gόnther's Frog ranges from southern China (including Hong Kong, Hainan and
Taiwan) to northern and central Vietnam. The species has also been
introduced to the island of Guam, in the western Pacific.
Its call was first heard in Singapore in 1997 and it has since become widely
established in ornamental ponds in parks and gardens.
Figs 1 and 2 : Example from Dempsey Hill, Singapore with vocal sacs inflated
(Fig. 1) and deflated (Fig. 2).
Fig 3 : Large adult from Singapore Botanic Gardens. Photo thanks to Noel
References : H17
Leong, T. M. & Lim, K. K. (2011). Occurrence
of Gόnthers Frog, Sylvirana guentheri (Amphibia: Anura: Ranidae)
in Singapore. Nature in Singapore, 4, 135-141.