Laephotis malagasyensis is a relatively small species, with a forearm length of 30 to 32 mm (1.2 to 1.3 in) and a body mass of 3.9 to 9 g (0.1 to 0.3 oz).

[7] In 2004, Steven Goodman and Julie Ranivo reviewed the Malagasy subspecies after collecting two more specimens[8] and concluded that it was distinct enough to be classified as a separate species, Neoromicia malagasyensis.

[3] Two years later, Paul Bates and colleagues reported on two more specimens[9] and showed that the bacula (penis bones) of N. malagasyensis and N. somalica are different, providing further evidence that they are distinct species.

However, they recommended that further research assess the degree of difference between N. malagasyensis and N. matroka (formerly in Eptesicus, but placed in Neoromicia by Bates and colleagues, and later placed in Laephotis), which occurs further east in Madagascar.

[11][12] Laephotis malagasyensis is one of at least six species of small vespertilionid bats ("pipistrelles") on Madagascar, in addition to L. matroka, L. robertsi, Pipistrellus hesperidus, P. raceyi, and Nycticeinops anchietae.

[20] Laephotis malagasyensis is known only from the vicinity of Isalo National Park, an area of about 2000 km2 (800 sq mi), in interior southwestern Madagascar.

[21] Peterson and colleagues reported that it had been collected near the village of Marinday,[2] but Goodman and Ranivo suggested that it may instead have come from near Ilakaka.

[8] Two specimens, a male and a female, were collected at different localities in Isalo National Park in early December 2002, both in mistnets near rivers.

[23] In view of its small known range and the threat of habitat destruction, the IUCN Red List assesses the species as "vulnerable"; further research is recommended on its roosting and dietary habits.