Stuenes (1989) indicated that Hippopotamus lemerlei was probably well adapted to the amphibious way of life observed in the extant Hippopotamus amphibius. She based her conclusion notably on the relatively prominent orbits and developed muzzle of this species. In terms of diet, cranio-mandibular morphology may also indicate similarity with Hip. amphibius (Stuenes 1989), i.e. a diet mainly based on fresh grass. Overall, Hippopotamus lemerlei seems to have been a dweller of freshwater rivers crossing the lowlands of Madagascar.

Hippopotamus lemerlei is mostly known from southern localities of coastal to lowland Madagascar (see a list of locality in Stuenes 1989). Last appearance datum of Madagascan dwarf hippopotamids remains uncertain. Most recent dates were provided through ¹⁴C dating and indicate c. 1000 AD (Dewar 1984, Burney et al. 2004). However, MacPhee and Flemming (1999) proposed it as recent on the basis of local oral tradition (Flacourt 1661; and see Burney and Ramilisonina 1999) and possible younger age of some localities. However, this may only reflect sporadic occurrence of Hippopotamus amphibius.

This species is now extinct.