Squirrels are members of the family Sciuridae, a family that includes small or medium-sized rodents. The squirrel family includes tree squirrels, ground squirrels, and flying squirrels. Squirrels are indigenous to the Americas, Eurasia, and Africa, and were introduced by humans to Australia. The earliest known fossilized squirrels date from the Eocene epoch, and among other living rodent families, the squirrels are most closely related to the mountain beaver and dormice.
Sciurinae is a subfamily of squirrels, uniting the flying squirrels with certain related tree squirrels. Older sources place the flying squirrels in a separate subfamily (Pteromyinae) and unite all remaining sciurids into the subfamily Sciurinae, but this has been strongly refuted by genetic studies.
The genus Sciurus contains most of the common, bushy-tailed squirrels in North America, Europe, temperate Asia, Central America and South America.
Vinckeia is a subgenus of the genus Plasmodium — all of which are parasitic alveolates. The subgenus Vinckeia was created by Cyril Garnham in 1964 to accommodate the mammalian parasites other than those infecting the primates.
Funambulus is a genus of rodents in the Sciuridae (squirrel) family, the only one in tribe Funambulini. It contains these species:
The slender-tailed squirrel is a species of rodent in the family Sciuridae found in Ivory Coast, Ghana, Liberia, and Sierra Leone. Its natural habitat is subtropical or tropical moist lowland forests.
The forest giant squirrel or Stanger's squirrel is a species of rodent in the family Sciuridae found in Angola, Benin, Burundi, Cameroon, the Central African Republic, the Republic of the Congo, the Democratic Republic of the Congo, Ivory Coast, Equatorial Guinea, Gabon, Ghana, Kenya, Liberia, Nigeria, Rwanda, Sierra Leone, Tanzania, Togo, and Uganda. Its natural habitats are subtropical or tropical moist lowland forests and plantations.
The Xerinae comprise a subfamily of squirrels, many of which are highly terrestrial. It includes the tribes Marmotini, Xerini, and Protoxerini.
The Protoxerini comprise a tribe of squirrels found in Africa. The 30 species in six genera are:
