The number of species in the genus is subject to change. In 2005, Thorington & Hoffman- whose taxonomic interpretation is followed by the IUCN website- accepted 28 species in the genus: Genus
Sciurus • Subgenus
Sciurus •
Allen's squirrel,
Sciurus alleni •
Arizona gray squirrel,
Sciurus arizonensis •
Mexican gray squirrel,
Sciurus aureogaster •
Eastern gray squirrel,
Sciurus carolinensis •
Collie's squirrel,
Sciurus colliaei •
Deppe's squirrel,
Sciurus deppei •
Japanese squirrel,
Sciurus lis •
Calabrian black squirrel,
Sciurus meridionalis •
Mexican fox squirrel,
Sciurus nayaritensis •
Fox squirrel,
Sciurus niger •
Peters's squirrel,
Sciurus oculatus •
Variegated squirrel,
Sciurus variegatoides •
Eurasian red squirrel,
Sciurus vulgaris •
Yucatan squirrel,
Sciurus yucatanensis • Subgenus
Otosciurus •
Abert's squirrel,
Sciurus aberti • Subgenus
Guerlinguetus •
Brazilian squirrel (Guianan squirrel),
Sciurus aestuans •
Yellow-throated squirrel,
Sciurus gilvigularis •
Red-tailed squirrel,
Sciurus granatensis •
Bolivian squirrel,
Sciurus ignitus •
Ingram's squirrel,
Sciurus ingrami •
Andean squirrel,
Sciurus pucheranii •
Richmond's squirrel,
Sciurus richmondi •
Sanborn's squirrel,
Sciurus sanborni •
Guayaquil squirrel,
Sciurus stramineus • Subgenus
Tenes •
Persian squirrel,
Sciurus anomalus • Subgenus
Hadrosciurus •
Fiery squirrel,
Sciurus flammifer •
Junín red squirrel,
Sciurus pyrrhinus • Subgenus
Hesperosciurus •
Western gray squirrel,
Sciurus griseus • Subgenus
Urosciurus •
Northern Amazon red squirrel,
Sciurus igniventris •
Southern Amazon red squirrel,
Sciurus spadiceus In 2015, 15–17 species were left in the genus
Sciurus after de Vivo & Carmignotto comprehensively reviewed South American Sciuridae for the first time in many decades and proposed numerous changes; synonymising some species and many subspecies, splitting another species, and naming new species. They followed
Joel Asaph Allen's unsatisfying 1914 attempt in splitting the genus
Sciurus by raising the South American subgenera to the rank of genus, adding
Urosciurus to
Hadrosciurus, and splitting the genus
Guerlinguetus in three. Their taxonomic treatment might also require
Sciurus deppei to be moved to
Notosciurus. A 2020 paper published on the taxonomy of
Sciurinae split
Sciurus into multiple new genera and elevated several subgenera. The paper included genetic sampling from almost all recognized species and recommends the following species assignments: •
Sciurus •
Persian squirrel,
S. anomalus •
Eurasian red squirrel,
S. vulgaris •
Calabrian black squirrel,
S. meridionalis •
Japanese squirrel,
S. lis •
Hesperosciurus •
Abert's squirrel,
H. aberti •
Western gray squirrel,
H. griseus •
Parasciurus •
Allen's squirrel,
P. alleni •
Arizona gray squirrel,
P. arizonensis •
Mexican fox squirrel,
P. nayaritensis •
Fox squirrel,
P. niger •
Peters's squirrel,
P. oculatus •
Neosciurus •
Eastern gray squirrel,
N. carolinensis •
Echinosciurus •
Mexican gray squirrel,
E. aureogaster •
Collie's squirrel,
E. colliaei •
Deppe's squirrel,
E. deppei •
Variegated squirrel,
E. variegatoides •
Yucatan squirrel,
E. yucatanensis •
Simosciurus •
S. nebouxii •
Guayaquil squirrel,
S. stramineus •
Guerlinguetus •
Brazilian squirrel,
G. aestuans •
G. brasiliensis •
Hadrosciurus •
Bolivian squirrel,
H. ignitus •
Northern Amazon red squirrel,
H. igniventris •
Junín red squirrel,
H. pyrrhinus •
Southern Amazon red squirrel,
H. spadiceus Additionally, the paper suggests moving
Andean squirrel back to subtribe
Microsciurina, the
dwarf squirrels, and assigns it to the newly described genus
Leptosciurus. The paper's findings agree with prior assessments to synonymize
Richmond's squirrel into
Red-tailed squirrel and reassigns the Red-tailed squirrel into the previously
monotypic South American genus
Syntheosciurus, also in
Microsciurina. The paper did not include genetic sampling or taxonomic suggestions for
gilvigularis,
meridionalis,
sanborni, or
flammifer. ==References==