Chalcorana raniceps — Borneo White-lipped Frog
Also known as:
Jade-backed Stream Frog, Copper-cheeked Frog, White-lipped Frog
This is Borneo's equivalent to the mainland's Chalcorana labialis. The taxonomic history is too confusing for me to repeat here. Note that Chalcorana megalonesa, which is also reasonably widespread in Borneo, looks basically exactly the same except that it is somewhat larger and tends to have a brownish back rather than a greenish back. So take my IDs of this species with an even larger grain of salt than usual.
Some authorities place this species in the genus Hylarana.
I initially thought that this large-ish individual was the similar-looking but significantly larger frog Chalcorana megalonesa, but I have since been informed that C. megalonesa is not known from this area of Sarawak.
Hmm, this frog is perhaps a bit of a mystery. Chalcorana raniceps is described on Frogs of Borneo as "a small green frog, sometimes with brown back". To my non-professional eyes, this frog looks extremely similar to C. raniceps in all ways except a total lack of green. But I don't see any other candidates. My best guess is that it is just an unusual color variation of C. raniceps, but who knows?
This was another big 'un, which I initially ID'ed as C. megalonesa before being educated about this matter on iNaturalist.
A reasonably small green frog, with a slightly brownish back. But maybe it is Chalcorana megalonesa instead?
- Inger, R. F., Stuebing, R. B., Grafe, T. U., Dehling, J. M. 2017. A Field Guide to the Frogs of Borneo, Third Edition
- Wahab, T. B., Das, I., Min, P. Y., Haas, A. 2014. A Photographic Guide to Frogs of Kubah National Park