By Kristen Schweighoefer
Geographic Range
The African pygmy squirrel is found in western Africa from Cameroon, northwestern Gabon, northwestern Congo, and Equatorial Guinea, including the island of Bioko. (Gharaibeh and Jones 1996)
Biogeographic Regions:
palearctic 
(native ).
Habitat
The African pygmy squirrel occurs in all types of forests in its geographic range. They have been observed in trees of all heights, but mainly at lower levels. This species lives in holes in tree trunks, but no nests have been observed. (Gharaibeh and Jones 1996, Rosevear 1969)
Terrestrial Biomes:
rainforest .
Physical Description
Like other sciurids, M. pumilio has a skull with an arched profile, rooted cheek teeth, a well developed postorbital process, a small infraorbital foramen and a sciurognathus lower jaw. The most striking feature of M. pumilio is its tiny, mouse-like size. This animal has a head and body length of 60-75 mm and a tail length of 50-60 mm. Myosciurus pumilio is no bigger than a man's thumb, making this species the smallest squirrel in the world. The dental formula is 1/1, 0/0, 1/1, 3/3 = 20. The upperparts are buffy green and the underside is olive white. The edges of this squirrel's rounded ears and borders of the eyelids are noticably white. (Gharaibeh and Jones 1996, Jansa and Myers 1997, Lawlor 1979, Nowak 1991, Rosevear 1969, Vaughan 1986)
Some key physical features:
endothermic ; bilateral symmetry .
Reproduction
Several pregnant females have been captured, each containing two embryos. The time of year was not given for these pregnant specimans. A lactating female was captured in late March, indicating that breeding occurs early in the year. The number of pairs of pelvic mammae seems to vary from 1-2, but since so few females have been observed, nothing can be concluded from this information. (Gharaibeh and Jones 1996, Nowak 1991, Rosevear 1969)
Key reproductive features:
gonochoric/gonochoristic/dioecious (sexes separate); sexual .
Behavior
The African pygmy squirrel is generally found alone, indicating that this is a solitary species. However, when two individuals are observed together, they seem to tolerate each other. These animals are known to be diurnal with respect to their foraging activities. They make a distinctive, low-intensity alarm call when threatened that draws attention to the source of danger. (Gharaibeh and Jones 1996, Nowak 1991, Rosevear 1969)
Key behaviors:
motile .
Food Habits
Not much is known about the food habits of this species. However, the stomach contents of three specimans of M. pumilio included bark fragments, fungus, oil droplets, and a few ants and termites, showing that perhaps this species is omnivorous. (Gharaibeh and Jones 1996, Nowak 1991)
Conservation Status
This species was classified as vulnerable in 1989 due to its low numbers and the fact that it could be quickly affected by deforestation because of its limited range. (Nowak 1991)
Other Comments
This species has also been known by the scientific names Myosciurus minutus and Myosciurus minutulus. (Lang 1922)
Contributors
Kristen Schweighoefer (author), University of Michigan.
