Microcebus jollyae has a head-body length of 13 cm, a tail length of just over 12 cm, a total length of 25 cm, and an average adult weight of just over 60 g (based on measurements of three adults from one site) (Louis et al., 2008). The dorsal coat is a uniform reddish- brown on both the body and the head. There are small white patches on the rostrum and under the mandible, the latter blending with the gray ventral coat (Louis et al., 2006a).
This species is known to occur in lower altitudinal coastal rain forest, but as of 2009 it had not been studied in the wild (Louis et al., 2006).
Microcebus jollyae occurs in the lowland coastal forest of eastern central Madagascar at Kianjavoto (its type locality), just south of the Mananjary River in the province of Fianarantsoa, and also Mananjary nearby, just to the northeast (Louis et al., 2006a).
There is insufficient information to determine the conservation status of M. jollyae, and the latest IUCN Red List assessment (2008) classified it as Data Deficient (DD). Its presence in a number of forests has been verified, but no estimates of population size are available. It occurs in the Kianjavato Forest near Ranomafana, which, although not an official government reserve, does receive some degree of local protection (Louis et al., 2006a). As of 2009 there were four individuals of this species in captivity, all in the Tsimbazaza Zoo in Antananarivo, Madagascar (E. E. Louis Jr., pers. obs.).
This mouse lemur can be seen in the wild in Kianjavato, a short distance by car from Ranomafana National Park. It is present as well in the forest along the road in the commune of Kianjavato. Lemur research projects have been undertaken in the forests of Kianjavato, and limited hotel accommodation is available.