Philautus umbra is a rare frog, only known from its type locality, Gunung Api, Gunung Mulu Natl. Park, >900 m asl. The depicted specimen was caught recently by Maximilian Dehling, probably for the first time since its first description in 1987 by J. Dring. With up to 35 mm snout-vent length in males and 38 mm in females, this species is fairly large for a Philautus. 

At daytime these frogs are almost uniformly blackish above, but lighten up to light grey during the night. Size, coloration, and body proportions make this frog unique. Note long digits and broad adhesive discs. The snout is rounded from above and in profile. The eyes are big and bulging. The dorsal skin texture is granular without conspicuous projecting tubercles. Tubercles are also absent at the heels. 

The reproductive mode of this species is unknown, as are many other aspects of its biology. However, the lack of open water accumulations in the karst forests on Gunung Api and very large eggs discovered in females, suggest direct-development.