The Sciurids or squirrels are a large family of rodents. It includes tree squirrels, ground squirrels, chipmunks, the marmots (which include woodchucks) and also the Eurasian flying squirrels, but not the African scaly-tailed flying squirrels, which belong to the family Anomaluridae and are not sciurids at all. Scuirids are found in all continents except Australasia and Antarctica.

The following list of genera is non-authoritative, and has not been placed in an order that reflects current taxonomic or cladistic research. The list given here classified the family into 280 species grouped into 48 genera, but it is important to realise that biological classification is never final or completely agreed, and other slightly different lists will be encountered. In addition, current studies in molecular evolution are likely to lead to some revision of the classification of this group, as of many others.

Scuirids are classified into two subfamilies, Sciurinae (tree and ground squirrels), and Petauristinae (flying squirrels):

Subfamily Petauristinae

• Aeretes, 1 species, the Groove-toothed Flying Squirrel, northeast China.
• Aeromys, 2 species, Thailand toBorneo.
• Belomys, 1 species, the Hairy-footed Flying Squirrel, southeast Asia.
• Eupetaurus, 1 species, the Woolly Flying Squirrel, Kashmir; rare.
• Glaucomys (American flying squirrels), 2 species, the Northern Flying Squirrel and the Southern Flying Squirrel, North America.
• Hylopetes, 7 species, southeast Asia.
• Iomys, 1 species, Horsfield's Flying Squirrel, Malaysia and Indonesia.
• Petaurillus (pygmy flying squirrels), 3 species, Borneo and Malaya.
• Petaurista (giant flying squirrels), 5 species, southeast Asia.
• Petinomys, 9 species, southeast Asia.
• Pteromys, 2 species, Finland to Japan (Japanese Dwarf Flying Squirrel).
• Pteromyscus, 1 species, the Smoky Flying Squirrel, southern Thailand to Borneo.
• Trogopterus, 1 species, the Complex-toothed Flying Squirrel, China.

Subfamily Sciurinae

Tree squirrels

• Callosciurus, 15 species, Asia.
• Epixerus (giant palm squirrels), 2 species, western Africa.
• Exilisciurus (pygmy squirrels), 6 species, Borneo and the Philippines.
• Funambulus (palm squirrels), 5 species, India.
• Funisciurus, 12 species, central and southern Africa.
• Glyphotes (sculptor squirrels), 2 species, Borneo.
• Heliosciurus (sun squirrels), 3 species, Africa.
• Hyosciurus, 1 species, the Celebes Long-nosed Squirrel, Sulawesi (Indonesia).
• Microsciurus (pygmy squirrels), 5 species, southern Central America and northern South America.
• Myosciurus, 1 species, the African Pygmy Squirrel, Cameroon and Gabon; the smallest sciurid.
• Nannosciurus, 1 species, the Black-eared Pygmy Squirrel, Indonesia.
• Paraxerus (bush squirrels), 12 species, Africa.
• Prosciurillus (dwarf squirrels), 5 species, Sulawesi (Indonesia).
• Protoxerus (giant squirrels), 2 species, Liberia to Kenya and Angola.
• Ratufa, 4 species, southeast Asia; the largest tree squirrels.
• Rhinosciurus, 1 species, the Shrew-faced Squirrel or Long-nosed Squirrel, Thailand, Malaya, Sumatra, and Borneo.
• Rubrisciurus, 1 species, the Red-bellied Squirrel, Sulawesi (Indonesia).
• Sciurillus, 1 species, the Neotropical Pygmy Squirrel, the Guianas, northeast Brazil, and the Amazon basin of Peru.
• Sciurus (typical tree squirrels), 31 species, Europe, the Middle East, northern Asia, North America, northern South America; the largest genus in the family, including the gray squirrels, fox squirrel and Eurasian red squirrel.
• Sundasciurus, 13 species, from Thailand to Indonesia and southern Philippines.
• Syntheosciurus (mountain squirrels), 2 species, Panama and Costa Rica; rare.
• Tamiasciurus (pine squirrels), 2 species (the American Red Squirrel and Douglas Squirrel), northern and western USA and most of Canada and Alaska.

Ground squirrels

• Ammospermophilus (Antelope squirrels), five species, southwestern USA and northern Mexico.
• Atlantoxerus, 1 species, Barbary ground squirrel, Morocco and Algeria.
• Cynomys (Prairie dogs), five species, North Dakota to central Mexico.
• Dremomys, four species, southeast Asia.
• Lariscus (striped ground squirrels), four species, southern Thailand, Malaysia, and Indonesia.
• Marmota (marmots), 14 species.
• Menetes, 1 species, Berdmore's Ground Squirrel, Burma to Indochina and Thailand.
• Rheithrosciurus, 1 species, Tufted Ground Squirrel, Borneo.
• Spermophilopsis, one species, Long-clawed Ground Squirrel, Middle East.
• Spermophilus, 36 species, from western Europe to Siberia and Alaska to northern Mexico; the largest genus of ground squirrels. Species include:
  • Spermophilus beecheyi - California Ground Squirrel.
  • Spermophilus brunneus - Idaho Ground Squirrel.
  • Spermophilus franklinii - Franklin's Ground Squirrel.
  • Spermophilus lateralis - Golden-mantled Ground Squirrel.
  • Spermophilus richardsonii - Richardson's Ground Squirrel.
• Tamias (chipmunks), 23 species, northern Mexico, most of the USA, Canada, and Siberia.
• Tamiops (striped squirrels), four species, China, Vietnam, Laos, Taiwan, Nepal, Burma, Malaya, and Cambodia.
• Xerus, four species, sub-Saharan Africa.

References

• Andrew's Squirrel Encyclopaedia, source of basic information above (http://www.geocities.com/yosemite/rapids/4362/sqrlenc.html)
• List of names of squirrel taxa (http://www.squirrels.org/names.html)