Finlayson's squirrel or the variable squirrel (''Callosciurus finlaysonii'', sometimes misspelled ''C. finlaysoni'') is a species of rodent in the family Sciuridae. It is found in Cambodia,

Laos Laos (, ''Lāo'' )), officially the Lao People's Democratic Republic ( Lao: ສາທາລະນະລັດ ປະຊາທິປະໄຕ ປະຊາຊົນລາວ, French: République démocratique populaire lao), is a socialist ...

Myanmar Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John C. Wells, Joh ...

, Thailand, and Vietnam. The species occurs in a wide range of wooded habitats, including gardens and parks in cities like Bangkok.Francis, C.M. (2008). A Guide to the Mammals of Southeast Asia. Pp. 144–145, 333–334. Princeton University Press. Ecology Asia
Variable or Finlayson's Squirrel
Retrieved 11 July 2018. It was named in honour of the Scottish naturalist and traveller George Finlayson. It has numerous

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

that vary greatly in appearance. One of these, ''C. f. bocourti'' (

syn. The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. * In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linnae ...

''C. f. floweri''), has been introduced to Singapore and two regions in Italy, probably a result of the species' popularity in the pet trade. It is possible that some of the '' Callosciurus'' squirrels introduced into Japan are also Finlayson's squirrels. Finlayson’s squirrel has also been introduced in the Philippines, particularly in the Greater Manila area where it is considered as an

invasive species An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad ...

Taxonomy and appearance

The Finlayson's squirrel has a head-and-body length of about and its tail is about long. There are currently 16 recognised subspecies. Additional subspecies are sometimes recognised. For example, some authorities recognise ''C. f. floweri'', while others consider it a

synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are all ...

of ''C. f. bocourti'' (as done in the following colour description). The subspecific name of ''C. f. boonsongi'' commemorates Thai zoologist and conservationist Boonsong Lekagul. The pelage colour in this species is extremely variable and the subspecies are often defined by this feature. For example, ''C. f. finlaysonii'' ( nominate) is overall whitish, ''C. f. albivexilli'', ''C. f. boonsongi'', ''C. f. germaini'' and ''C. f. nox'' are overall blackish (first with white tail-tip, second occasionally with white underside, face and feet), ''C. f. annellatus'' is overall rufous with a light band at the base of the tail, ''C. f. bocourti'' is whitish below with highly variable colour of the upperparts (whitish, grey, blackish,

olive The olive, botanical name ''Olea europaea'', meaning 'European olive' in Latin, is a species of small tree or shrub in the family Oleaceae, found traditionally in the Mediterranean Basin. When in shrub form, it is known as ''Olea europaea'' ...

-brownish or reddish), ''C. f. cinnamomeus'' is overall reddish with a dark mid-back, ''C. f. ferrugineus'' is reddish-brown, ''C. f. harmandi'' has brownish upperparts, orange-red underparts and light grey tail, ''C. f. menamicus'' is reddish or orangish, often has greyish legs and flanks, and sometimes a white belly, and ''C. f. sinistralis'' has grizzled upperparts, reddish underparts and reddish tail with a pale band at the base.Boonkhaw, Phadet, Prayoon, Umphornpimon, Kanchanasaka, Budsabong, Hayashi, Fumio, Tamura, Noriko (2017). Colour polymorphism and genetic relationships among twelve subspecies of Callosciurus finlaysonii in Thailand. ''Mammalian Biology – Zeitschrift für Saugetierkunde 85'', 6–13. Unnamed populations also remain (for example, a population in central Laos is shiny black with red tail and shoulder/chest region) and even within described subspecies there are often some individual variations. As currently defined, Finlayson's squirrel may comprise more than one species. ''C. f. ferrugineus'' has been treated as a separate species. A genetic study of the 12 subspecies in Thailand, including 7 from the mainland and 5 from islands, found that they belonged in six

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

s, which often were separated by water (large rivers in the mainland and the sea for the islands). The study also revealed that the

mitochondrial DNA Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial D ...

of this species compared to the closely related

Pallas's squirrel Pallas's squirrel (''Callosciurus erythraeus''), also known as the red-bellied tree squirrel, is a species of squirrel native to Greater China, India, and Southeast Asia. Description Pallas's squirrel is a medium-sized tree squirrel, with ...

is not

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

Behavior

Like other squirrels of its genus (the "beautiful squirrels", '' Callosciurus''), Finlayson's squirrel is normally a canopy-dweller, feeding mainly on fruit. Field evidence suggests that it has the usual form of dichromatic mammalian color vision, which may enable it to discriminate ripe from unripe fruits.Tamura, N., Fujii, Y., Boonkeow, P., & Kanchanasaka, B. (2015). Colour vision and food selection of ''Callosciurus finlaysonii'' (Sciuridae) in tropical seasonal forests. ''Journal of Tropical Ecology, 31'', 449–457.

References

External links

Wildlife Singapore Photos and description

Photo gallery showing some of the variations of Finlayson's Squirrel.
{{Taxonbar, from=Q2086835 Callosciurus Mammals of Southeast Asia Rodents of Myanmar Rodents of Thailand Rodents of Laos Fauna of Italy Mammals described in 1823 Taxa named by Thomas Horsfield Taxonomy articles created by Polbot