Previously this Leptobrachella has been confused with L. mjobergi, however Eto et al. (2018) established a new species, Leptobrachella fusca. L. fusca has only been reported from North Kalimantan (Bulungan Regency). It is unclear whether or not this species reaches neighboring Sabah or Sarawak.

The adult males holotype measures 16.3 mm snout-vent-length. as the name suggests, this species is mostly brown, above and below. Unlike most other species in the genus, L. fusca has a uniformely dark pigmentation on the belly (L. parva has belly pigmentation but paler). Elongate glands are present ventrolaterally along the abdomen. Large dark markings of blotches on flanks are absent in L. fusca. The lineae masculinae (whitish connective tissue lines along the ventral side) are invisible through ventral skin, at least in preservation. Toe webs are rudimentary.

Tadpoles, reproduction and other aspects of natural history are unknown.