Head and body length of the type specimen, an adult female, is 92 mm and tail length is 78 mm. The upper parts are smoky gray, and the underparts are slightly paler. The tail is brownish above and below, except for a whitish terminal area of some 15 mm. This small, mouselike rodent is not modified for aquatic life. It is distinguished from other members of the subfamily Hydromyinae by its small molar teeth and fairly long muzzle, as well as other dental and skeletal features.
Females have four mammae.