sciurini

They suggested that it was probably a tree squirrel and related to the Sciurini.

The same studies also provided insights into the interrelationships of genera within Sciurini.

The name "Sciurini" was first employed by Hermann Burmeister in 1854, who used it for the entire squirrel family.

The development of sphenopalatine vacuities has also been used to distinguish among members of the Sciurini group of squirrels.

His definition of Sciurini was similar to Simpson's, but he no longer considered Rheithrosciurus to be incertae sedis.

Tribe Sciurini (mostly American tree squirrels)

Freudenthalia (fossil, early Miocene of Europe; assignment to Sciurini "uncertain")

The 2005 discovery of S. olsoni provided evidence that the origin of the Sciurini lies in North America.

Plesiosciurus from the Miocene of China has been interpreted as a member of Sciurini, but is unlikely to belong to the tribe.

A Miocene squirrel from France and Spain, Freudenthalia, has been tentatively placed in Sciurini.

In their 1997 update to Simpson's classification, McKenna and Bell retained a similar definition for Sciurini, but also included several extinct genera, as follows:

Emry and Korth, who re-described the animal in 1996, classified it within Sciurini and speculated that other squirrels may have evolved from animals similar to Sciurini squirrels.

They removed Sciurillus from Sciurini, placed Tamiasciurus in it, and classified Sciurini with the flying squirrels (tribe Pteromyini) in a subfamily Sciurinae.

The Sciurinae contains the flying squirrels (Pteromyini) and the Sciurini, which among others contains the American tree squirrels; the former have often been considered a separate subfamily, but are now seen as a tribe of the Sciurinae.

A morphological study of Central American Sciurini also found that Microsciurus and Syntheosciurus are part of the Sciurus radiation, and suggested that Syntheosciurus be lumped into Sciurus while further work is needed on Microsciurus.

The Oligocene to early Miocene North American genera Protosciurus and Miosciurus are classified in Sciurini and may have given rise to the earliest known member of Sciurus, S. olsoni from the early late Miocene (about 10 million years ago) of Nevada.