[1][2] Shell relatively small, with a conical spire issuing from a rather broad base.

Aperture wide, with separated angular and parietal lamellae; columella, upper and lower palatal teeth large, infraparietal, basal and interpalatal teeth small.

P. serpa resembles Gyliotrachela modesta in general form, but the latter differs in its disjunct ultimate whorl and lesser-developed apertural armature.

[2] Paraboysidia serpa is endemic to the limestone karst of Bukit Baling, Kedah, Malaysia.

It occurs among lowland dipterocarp woodlands which are threatened by desiccation (which has been tied to population declines in karst-endemic fauna), and possibly pollution from quarrying operations or changing forest structure.