This species has been described from Gunung Penrissen in western Sarawak, around 1000 m a.s.l. Adult males measure approx. 33 mm in snout-vent length, and adult females 36–37 mm. However, we tentatively also assign a specimen from Gunung Pueh (photos) to this species. 

Limnonectes oreibates displays the typical characteristics of the palavanensis-species group, including body size <40 mm, low and inconspicuous odontoid processes on the lower jaw in both sexes, and a finely shagreened dorsal surface with prominent longitudinal dorsolateral glandular ridges. The interorbital distance is equal to or greater than the width of the upper eyelid. The toes are not fully webbed, and a horseshoe-shaped dermal ridge is present in the center of the dorsum just behind the point of forelimb insertion.

This species is distinguished from all other relatives in the palavanensis-species group by a combination of certain traits: The toe webbing is reduced; the supratympanic fold is weakly curved; a clearly visible pineal spot is located in front of the level of the upper eyelids; the vomerine ridges are short and widely spaced; and the postpalpebral ridge is present but weakly developed. Both lumbar and median dorsal ridges are absent.

The advertisement call consists of a series of up to 11 slow chirp.