Microcebus ravelobensis, Zimmerman, Ehresmann, Zeitemann, Radespiel, Randrianambinina & Rakotoarison, 1997

Russell A. Mittermeier, Anthony B. Rylands & Don E. Wilson, 2013, Cheirogaleidae, Handbook of the Mammals of the World – Volume 3 Primates, Barcelona: Lynx Edicions, pp. 28-65 : 53

5.

Golden-brown Mouse Lemur

Microcebus ravelobensis

French: Microcebe doré / German: Goldbrauner Mausmaki / Spanish: Lémur ratén castano dorado

Other common names: Lac Ravelobe Mouse Lemur, Ravelobe Mouse Lemur

Taxonomy. Microcebus ravelobensis Zimmermann, E. et al, 1997 ,

Madagascar, province of Mahajanga, RF Ankarafantsika, Station Forestiere d’Ampijoroa (16° 35S, 46° 32’ EK).

This species is monotypic.

Distribution. NW Madagascar; the range is still incompletely known, but it is believed to be restricted to the Ankarafantsika region; the type specimen was collected adjacent to Lac Ravelobe in Ankarafantsika National Park, and the species is also known to occur in the Mariarano Classified Forest, just N of Mahajanga.

Descriptive notes. Head—body 12-13 cm, tail 15-17 cm; weight 57 g. The Goldenbrown Mouse Lemur is a large mouse lemur. The pelage is short and dense. The dorsal side, crown, and ears are rufous and mottled, and the underside is mottled or bicolored yellow to whitish. The mid-dorsal stripe is poorly defined. Regions between the eyes are a prominent pale grayish changing to cinnamon toward the crown, and eye-rings are dark brown. The tail is brown and darker at the tip. Ears are long and naked.

Habitat. Dry deciduous lowland forest up to elevations of 500 m. The Golden-brown Mouse Lemur is sometimes found in degraded patches of forest. It appears to prefer forests with a lower canopy height and more lianas than those inhabited by Gray Mouse Lemurs ( M. murinus ), and it also uses tree holes less often.

Food and Feeding. The Golden-brown Mouse Lemur feeds on gum, insect excretions, nectar, fruits, leaves, and animal matter. Gum is a dietary staple during all seasons, and insect excretions seem to play a larger role in its diet than in the diet of the sympatric Gray Mouse Lemur . In contrast, fruits seem more important to the Gray Mouse Lemur than to the Golden-brown Mouse Lemur . Dietary overlap between the two species is only partial. Shared food resources include gum from Astrotrichilia asterotricha ( Meliaceae ), Baudouinia flueggeiformis ( Fabaceae ), Poupartia silvatica ( Anacardiaceae ), and Rhopalocarpus similis ( Sphaerosepalaceae ); insect excretions; fruits from Noronhia boinensis ( Oleaceae ) and Strychnos madagascariensis ( Loganiaceae ); and arthropods. The Golden-brown Mouse Lemur does not store fat in its tail like the sympatric Gray Mouse Lemur .

Breeding. Female Golden-brown Mouse Lemurs begin estrus at the end of August, whereas the sympatric Gray Mouse Lemur does not do so until mid-September.

Activity patterns. The Golden-brown Mouse Lemur is nocturnal and arboreal. Females rest more and forage and travel less during the late dry and early wet season than during the rest of the year.

Movements, Home range and Social organization. The Golden-brown Mouse Lemur is reported to be more aggressive than the sympatric Gray Mouse Lemur , although most social encounters are not agonistic and those that are usually occur right before the mating season. Nests are constructed in tangles of vines and dead leaves. The Golden-brown Mouse Lemur uses a broadervariety ofless protected daytime sleeping sites (e.g. branches, lianas, and leaves) than the Gray Mouse Lemur . Home ranges of individual male and female Golden-brown Mouse Lemurs and male-male and female-female dyads overlap and are temporally stable. Males do not seem to spatially monopolize females. The social system of the Golden-brown Mouse Lemur appears to be a dispersed multimale-multifemale system with a promiscuous mating pattern. Sleeping associations seem to remain stable over time and are most often mixed-sex groups, although all-female sleeping groups also occur.

Status and Conservation. CITES Appendix I. Classified as Endangered on The [UCN Red List. The Golden-brown Mouse Lemuris threatened mainly by habitat loss due to slash-and-burn cultivation, seasonal bush fires, and predation by feral cats and dogs. The only protected area that it is known from is Ankarafantsika National Park, but it has also been reported from Mariarano Classified Forest, which offers some degree of protection. Almost all sampled populations of the Golden-brown Mouse Lemur , along with those of the other north-western Microcebus species (Ambarijeby Mouse Lemur , M. danfossi , and Bongolava Mouse Lemur , M. bongolavensis ), show genetic evidence of a relatively rapid crash in population size of about two orders of magnitude. This crash likely occurred within the last 500 years, thus coinciding with accelerated deforestation due to human population expansion in Madagascar.

Bibliography. Andriantompohavana et al. (2006), Garbutt (1999), Groves (2001), Mittermeier et al. (2010), Olivieri et al. (2008), Radespiel, Ehresmann & Zimmermann (2003), Randrianambinina, Rakotondravony et al. (2003b), Randrianambinina, Rasoloharijaona et al. (2003), Rasoloarison et al. (2000), Rendigs et al. (2003), Thoreén et al. (2011), Weidt et al. (2004), Zimmermann, Cepok et al. (1998), Zimmermann, Ehresmann etal. (1997).

Figures

1. Gray Mouse Lemur (Microcebus murinus), 2. Gray-brown Mouse Lemur (Microcebus griseorufus), 3. Madame Berthe’s Mouse Lemur (Microcebus berthae), 4. Peters’s Mouse Lemur (Microcebus myoxinus), 5. Golden-brown Mouse Lemur (Microcebus ravelobensis), 6. Bongolava Mouse Lemur (Microcebus bongolavensis), 7. Ambarijeby Mouse Lemur (Microcebus danfossi), 8. Margot Marsh’s Mouse Lemur (Mucrocebus margotmarshae), 9. Sambirano Mouse Lemur (Microcebus sambiranensis), 10. Nosy Be Mouse Lemur (Microcebus mamaratra), 11. Tavaratra Mouse Lemur (Microcebus tavaratra), 12. Montagne d’Ambre Mouse Lemur (Microcebus arnholdi), 13. Rufous Mouse Lemur (Mucrocebus rufus), 14. Jolly’s Mouse Lemur (Microcebus jollyae), 15. Gerp’s Mouse Lemur (Microcebus gerpi), 16. Goodman’s Mouse Lemur (Microcebus lehilahytsara), 17. Simmons’s Mouse Lemur (Microcebus simmonsi), 18. Anjiahely Mouse Lemur (Mucrocebus macarthuri), 19. Mittermeier’s Mouse Lemur (Microcebus mittermeieri)

Distribution. NW Madagascar; the range is still incompletely known, but it is believed to be restricted to the Ankarafantsika region; the type specimen was collected adjacent to Lac Ravelobe in Ankarafantsika National Park, and the species is also known to occur in the Mariarano Classified Forest, just N of Mahajanga.