Theloderma horridum is a secretive animal. Due to its coloration and warty skin texture, it is difficult to discern when sitting on bark. On Borneo it has been reported from northern parts (Sabah). 

Apart from the bark-mimicing skin, very broad orange-colored finger tips are a hallmark of this mid-size frog (approx. 40–50 mm). The specimen presented here is from Pulau Tioman.

This species is a phytothelm breeder: tadpoles develop in treeholes. A predominantly arboreal lifestyle high up in the trees could explain the rare sightings of these frogs. 

More information about the breeding biology of related species from mainland Asia has recently been gathered by captive breeding. It has been shown that eggs were attached at or just above the water level in phytothelms. If this applies to T. horridum as well needs still to be confirmed.