Dicrostonyx groenlandicus
| Nearctic Collared Lemming
(Dicrostonyx groenlandicus) | |
|---|---|
| Range | |
 | |
| Taxonomic classification | |
| Order: | Rodentia |
| Suborder: | Supramyomorpha |
| Infraorder: | Myomorphi |
| Superfamily: | Muroidea |
| Family: | Cricetidae |
| Subfamily: | Arvicolinae |
| Tribe: | Dicrostonychini |
| Genus: | Dicrostonyx |
| Subgenus: | Dicrostonyx (subgenus) |
| Binomial details | |
| Dicrostonyx groenlandicus (Traill in W. Scoresby, 1823) | |
| Other resources | |
| Full taxonomic details at MDD | |
Description
From Handley (1953) for the Parry Islands of the Canadian Archipelago: "Adult summer coloration: Mass effect bright gray above; dorsum, except for lighter areas on shoulders, rather uniformly colored from snout to tail; light band on dorsal hairs typically pure white; subapical orange band on dorsal hairs narrow or absent and contributing little to mass color effect; orange of sides typically invading dorsum in shoulder region only slightly; faint but readily discernible black median dorsal stripe extending from snout to base of tail; rump gray; ear patches between Sanford's Brown and Amber Brown; tail and feet whitish; belly washed with orange ranging in hue from Pale Ochraceous-Buff to Sanford's Brown, darkest color concentrated along midline and on chest, forming and obscure collar; flanks, especially at base of fore leg, tinged with orange of same hue as belly. Juvenal summer coloration: Dorsum grayish-brown, varying with season and individual from Snuff Brown to Sudan Brown; shoulders lighter than remainder of dorsum; black median dorsal stripe well defined and extending from forehead to base of tail; underparts varying from buffy to almost white; throat collar poorly developed. Winter pelage: white."
From Handley (1953) for the southern half of Baffin Island, Northwest Territories, Canada: "Adult summer coloration: Black in dorsal pelage reduced and light band on dorsal hairs pale buff, rendering mass effect between Avellaneous and Drab; black median dorsal stripe not well defined; ear patch Ochraceous-Tawny; feet and tail whitish; orange wash on flanks reduced and not extending on dorsum in shoulder region; underparts typically pale (Pale Ochraceous-Buff to almost white); throat collar and orange median ventral line pale, but well defined because of lighter background. Juvenal summer coloration: Dorsum relatively dark (Sayal Brown); shoulders scarcely differentiated from remainder of dorsum; black median dorsal line well defined; belly light buff to whitish; throat collar poorly developed. Winter pelage: white."
Members of Dicrostonyx are the only rodents in North America that turn white in winter.
External measurements
Length measurements are in millimeters (mm) and weight measurements are in grams (g), unless stated otherwise. If available, the sample size (n=) is provided. If a range is not provided and n= is not given, then the listed measurement represents an average.
| Part of range | Reference | Total length | Tail length | Hindfoot length | Ear length | Mass |
|---|---|---|---|---|---|---|
| Canada (Baffin Island, Nunavut Territory) | Handley (1953) | 129 (type only) | 18 (type only) | 12 (type only) | ||
| Prince Patrick Island, Northwest Territories, Canada | Handley (1953) | 140–154 (n=12, including type) | 23–28 (n=12, including type) | 19–23 (n=12, including type) |
Skull
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Lateral view of the skull of Dicrostonyx groenlandicus. -
Dorsal view of the skull of Dicrostonyx groenlandicus. -
Ventral view of the skull of Dicrostonyx groenlandicus. -
The upper incisors of Dicrostonyx groenlandicus lack grooves. -
Upper molars of Dicrostonyx groenlandicus. M1 and M2 usually terminate with a narrow lingual and labial loop (Naughton, 2012). -
Lower molars of Dicrostonyx groenlandicus. Second and third lower molars (m2 and m3) typically begin with narrow loops (Naughton, 2012). -
Dorsal view of the skull of a juvenile Dicrostonyx groenlandicus.
References
Handley CO. 1953. Three new lemmings (Dicrostonyx) from arctic America. Journal of the Washington Academy of Sciences 43(6):197-200.
Naughton D. 2012. The natural history of Canadian mammals. Toronto (ON, CA): University of Toronto Press.
Scoresby W. 1823. Journal of a Voyage to the Northern Whale-Fishery; including Researches and Discoveries on the Eastern Coast of West Greenland, made in the Summer of 1822, in the Ship Baffin of Liverpool. Archibald Constable & Co., Edinburgh, 472 pp.