P. beiranus has a disjunctive distribution, occurring in at least two quite distinct areas: (1) the coastal plain of central Mozambique within the floodplain of the Pungwe River (alternatively known as the Pungwe Flats), northward to Thuchila in southern Malawi; and (2) floodplains in the Middle Zambezi River catchment area in central and southwestern Zambia. The species is under-recorded, and probably occurs more broadly than the officially reported range, especially between the two noted disjunctive areas. Elevation of occurrence is between sea level and at least 1000 meters above mean sea level (Tandy et al. 2004).

With regard to the westernmost population element, the extent is at least as far as the Barotse floodplains.