Oriental giant squirrels are very large tree squirrel

Tree squirrel

Tree squirrels include over a hundred species that are found on all continents except Antarctica, and are the members of the squirrel family most commonly referred to as "squirrels"...

s from the genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 Ratufa in the subfamily Ratufinae. They are a distinctive element of the fauna

Fauna

Fauna or faunæ is all of the animal life of any particular region or time. The corresponding term for plants is flora.Zoologists and paleontologists use fauna to refer to a typical collection of animals found in a specific time or place, e.g. the "Sonoran Desert fauna" or the "Burgess shale fauna"...

 of south

South Asia

South Asia, also known as Southern Asia, is the southern region of the Asian continent, which comprises the sub-Himalayan countries and, for some authorities , also includes the adjoining countries to the west and the east...

 and southeast Asia

Southeast Asia

Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...

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There are four living species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of oriental giant squirrels:

• Cream-coloured giant squirrel
  Cream-coloured Giant Squirrel
  The cream-coloured giant squirrel is a large tree squirrel in the genus Ratufa found in Brunei, Indonesia, Malaysia, and Thailand. It is probably extinct in Singapore, as no recent sightings have been made...
  
  , Ratufa affinis
• Black giant squirrel
  Black Giant Squirrel
  The black giant squirrel is a large tree squirrel in the genus Ratufa native to the Indomalayan zootope...
  
  , Ratufa bicolor
• Indian giant squirrel
  Indian Giant Squirrel
  The Indian giant squirrel, or Malabar giant squirrel, is a large tree squirrel species genus Ratufa native to India. It is a large-bodied diurnal, arboreal, and herbivorous squirrel found in South Asia.-Description:...
  
  , Ratufa indica
• Grizzled giant squirrel
  Grizzled Giant Squirrel
  The grizzled giant squirrel is a large tree squirrel in the genus Ratufa found in the highlands of the Central and Uva provinces of Sri Lanka, and in patches of riparian forest along the Kaveri River and in the hill forests in the Tamil Nadu and Kerala states of southern India...
  
  , Ratufa macroura

In prehistoric times this lineage was more widespread. For example, animals very similar to Ratufa and possibly belonging to this genus - at least belonging to the Ratufinae - were part of the early Langhian

Langhian

The Langhian is, in the ICS geologic timescale, an age or stage in the middle Miocene epoch/series. It spans the time between 15.97 ± 0.05 Ma and 13.65 ± 0.05 Ma . The Langhian was a continuing warming period defined by Lorenzo Pareto in 1864, it was originally established in the Langhe area north...

 (Middle Miocene

Middle Miocene

The Middle Miocene is a sub-epoch of the Miocene Epoch made up of two stages: the Langhian and Serravallian stages. The Middle Miocene is preceded by the Early Miocene....

, some 16-15.2 million years ago) Hambach fauna of Germany

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

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