Finlayson's squirrel
{{short description|Species of "beautiful" squirrel from Southeast Asia}}
{{Speciesbox
| name = Finlayson's squirrel
| image = Callosciurus finlaysonii - Finlayson%27s squirrel (variable squirrel).jpg
| image_caption = C. f. bocourti in Bangkok, Thailand
| status = LC
| status_system = IUCN3.1
| genus = Callosciurus
| species = finlaysonii
| authority = (Horsfield, 1823)
| range_map = Callosciurus finlaysonii distribution.png
| subdivision_ranks = Subspecies
| subdivision =
16 subspecies:
- C. f. finlaysonii
- C. f. albivexilli
- C. f. folletti
- C. f. frandseni
- C. f. germaini
- C. f. harmandi
- C. f. trotteri
- C. f. annellatus
- C. f. bocourti
- C. f. boonsongi
- C. f. cinnamomeus
- C. f. ferrugineus
- C. f. menamicus
- C. f. nox
- C. f. sinistralis
- C. f. williamsoni
}}
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, Myanmar, 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. {{isbn|978-0-691-13551-9}}Ecology Asia: [https://www.ecologyasia.com/verts/mammals/variable-squirrel.htm 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 that vary greatly in appearance. One of these, C. f. bocourti (syn. C. f. floweri), has been introduced to Singapore and two regions in Italy, probably a result of the species' popularity in the pet trade.Bertolino, S., & Lurz, P. W. W. (2013). Callosciurus squirrels: worldwide introductions, ecological impacts and recommendations to prevent the establishment of new invasive populations. Mammal Review, 43, 22–33. {{doi|10.1111/j.1365-2907.2011.00204.x}} It is possible that some of the Callosciurus squirrels introduced into Japan are also Finlayson's squirrels.Kuramoto, T., Torii, H., Ikeda, H., Endo, H., Rerkamnuaychoke, W., & Oshida, T. (2012). Mitochondria DNA sequences of Finlayson's squirrel found in Hamamatsu, Shizuoka Prefecture, Japan. Mammal Study, 37, 63–67
Finlayson's squirrel has also been introduced in the Philippines, particularly in the Greater Manila area where it is considered as an invasive species.{{Cite web|url=https://businessmirror.com.ph/2021/05/31/invasive-squirrel-species-seen-as-threat-to-wildlife-and-farms/|title = Invasive squirrel species seen as threat to wildlife and farms | Jonathan L. Mayuga| website=BusinessMirror |date = 31 May 2021}}
Taxonomy and appearance
The Finlayson's squirrel has a head-and-body length of about {{convert|21-22|cm|in|abbr=on}} and its tail is about {{convert|22-24|cm|in|abbr=on}} 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 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.Moore, J.C., Tate, G.H.H. (1965). A study of the diurnal squirrels, Sciurinae, of the Indian and Indo-Chinese subregions.
Fieldiana Zoology 48:1–351.
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-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 Säugetierkunde 85, 6–13. {{doi|10.1016/j.mambio.2017.02.001}} 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.{{cite journal| last1=Timmins | first1=R.J. | last2=Duckworth | first2=J.W. | year=2008 | title=Diurnal squirrels (Mammalia Rodentia Sciuridae) in Lao PDR distribution, status and conservation | journal=Tropical Zoology | volume=21 | issue=1 | pages=11–56 }}
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 clades, 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 of this species compared to the closely related Pallas's squirrel is not monophyletic. A subsequent study recommended that, to maintain monophyletic species, flavimanus and griseimanus, which traditionally are recognized as being subspecies of Pallas's squirrel in southeastern Indochina (central and southern Vietnam, adjacent parts of Cambodia and southern Laos), should be considered part of Finlayson's squirrel. The study also found that flavimanus, as traditionally defined, actually consists of at least two clearly separate lineages, both part of Finlayson's squirrel.{{cite journal| last1=Balakirev | first1=A.E. | last2=Rozhnov | first2=V.V. | year=2008 | title=Taxonomic revision of beautiful squirrels (Callosciurus, Rodentia: Sciuridae) from the Callosciurus erythraeus/finlaysonii complex and their distribution in eastern Indochina | journal=Raffles Bulletin of Zoology | volume=67 | pages=459–489 | doi=10.26107/RBZ-2019-0037 }}
File:Callosciurus finlaysonii 85959681.jpg|C. f. bocourti mating pair in Nonthaburi, Thailand (colour difference is individual, not related to male/female)
File:Callosciurus finlaysonii 177035226.jpg|C. f. bocourti in Wang Nam Khiao, Thailand
File:Callosciurus finlaysonii cinnamomeus 86117364.jpg|C. f. cinnamomeus in Khao Soi Dao, Thailand
File:Callosciurus finlaysonii 99592168.jpg|C. f. germaini on Côn Đảo, Vietnam
Behavior
File:Finlayson's squirrel (Callosciurus finlaysonii).jpg, Bangkok, Thailand]]
Like other squirrels of its genus (the "beautiful squirrels", Callosciurus), Finlayson's squirrel is normally a canopy-dweller, feeding mainly on fruit.Kitamura, S., Yumoto, T., Poonswad, P., Chuailua, P., Plongmai, K., Maruhashi, T., & Noma, N. (2002). Interactions between fleshy fruits and frugivores in a tropical seasonal forest in Thailand. Oecologia, 133, 559–572. 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
{{Reflist}}
External links
- [https://web.archive.org/web/20110716084253/http://www.wildsingapore.per.sg/discovery/factsheet/squirrelvariable.htm Wildlife Singapore Photos and description]
- [http://siamensis.org/content/2339 Photo gallery showing some of the variations of Finlayson's Squirrel.]
{{S. Callosciurinae nav}}
{{Taxonbar|from=Q2086835}}
Category:Mammals of Southeast Asia
Category:Mammals described in 1823