Flora of the Canadian Arctic Archipelago
English: Snow buttercup,
French: Renoncule nivale, renouncle des neiges,
Inuktitut: Iguttait, niqingittuaq, nunarait.
Ranunculaceae, Buttercup family.
Published in Sp. Pl. 553. 1753.
Type: Linnaean Herbarium 715.38 (LINN) lectotype, selected by L.D. Benson, Amer. Midl. Naturalist 52: 350. 1954.
Synonymy. Ranunculus nivalis f. subglobosus Polunin, Bull. Natl. Mus. Canada 94 (Biol. Ser. 24): 215. 1940.
Vegetative morphology. Plants 5–20 cm high; perennial herbs; caespitose. Only fibrous roots present. Roots slender. Ground level or underground stems absent. Caudex present (short, fibrous). Aerial stems erect. Aerial stem trichomes erect. Leaves not heterophyllous; mainly basal and distributed along the stems; alternate; persistent, or dying annually and non-persistent. Petioles 12–45 mm long. Leaf blade bases cordate, or truncate. Blades (5–)9–15(–20) mm long, 12–26(–30) mm wide, reniform, flat, veins palmate. Blade adaxial surface glabrous. Blade abaxial surface glabrous. Blade margins flat, blades lobed (basal leaf blades 3-lobed, and at least the lateral segments lobed again). Blade margins crenate, with teeth toward the apex. Hydathodes present but inconspicuous. Blade apices rounded (apiculate).
Reproductive morphology. Flowering stems solitary; with leaves; pilose (sparsely). Flowers solitary (each flowering stem usually with one flower), or in inflorescences (rarely). Inflorescences racemose. Flowers large. Sepals conventional; 5; free; 3–5 mm long; 6–8 mm wide; green; herbaceous; non-accrescent. Calyx hairy (densely hispid). Calyx hairs brown. Petals conventional; free; 5(–6); white, or yellow (fading to white); obovate; unlobed; (8–)9–11(–12) mm long; 8–12 mm wide. Stamens 15–25; stamen filaments glabrous. Anthers 0.8–1.2 mm long. Nectaries present (nectary scale glabrous, forming a pocket). Receptacle 2–9 mm high (2 mm long in flower, 6–9 mm long in fruit; most of the receptacle is glabrous, but there are often a few rusty brown hairs on the apex). Ovary carpels 70–90; apocarpous. Stigmas per ovary 1. Placentation parietal. Ovules per ovary 1. Fruit stalk 5–9 mm long; dry; an aggregate of achenes; obovate (cylindric to ovoid-cylindric); green at maturity; 7–14 mm long; 5–6 mm wide (achenes 2–2.5 × 1.2–1.7 mm, glabrous, beak slender, straight, 1–2 mm); indehiscent. Styles remaining straight.
Chromosome information. 2n = 48 and 56.
2n (5x) = 40. Nygren, in Löve and Löve (1948, northern Europe);
2n (6x) = 48. Flovik (1936, 1940, Svalbard); Nygren, in Löve and Löve (1948, northern Europe); Jørgensen et al. (1958, Greenland); Zhukova (1966, northeastern Asia; 1980, southern Chukotka; 1982, northeastern Asia); Hedberg (1967, northern Canada, 2n = about 45); Knaben and Engelskjøn (1967, Norway); Zhukova and Tikhonova (1971, Chukotka); Zhukova and Petrovsky (1972, Wrangel Island, 1976, 1980, western Chukotka); Zhukova et al. (1973, 1977, northeastern Asia); Göpfert (1974); Packer and McPherson (1974, northern Alaska); Krogulevich, in Malyshev (1976b, central Siberia); Engelskjøn (1979, Norway); Krogulevich (1976a, northern Siberia; 1984, Siberia); Dalgaard (1989, western Greenland);
2n = 56 (7x). Langlet (1932, 1936); Nygren, in Löve and Löve (1948, northern Europe); Krogulevich (1976b, northern Siberia); Sokolovskaya et al. (1989, northeastern Asia).
Ploidy levels recorded 5x/6x/7x.
Ecology and habitat. Substrates: wet meadows, snow patches, along streams. This species is almost always a calcifuge, whereas R. sulphureus is usually caliphilous. Ranunculus nivalis is found on slightly drier and often much more humic sites. Ranunculus sulphurus is much more typical of snow banks. When these species are found growing together, R. nivalis blooms earlier and is well into fruit before R. sulphureus begins to flower (Elven, personal communication, 2005). Growing in wet moss by brooks and in herbmats, often near the edge of a melting snowbank (Porsild 1957).
North American distribution. Alaska, Yukon, Northwest Territories Islands, continental Northwest Territories, Nunavut Islands, continental Nunavut, northern Quebec, Labrador. Range in the Canadian Arctic Archipelago widespread. Common. Arctic, alpine. Arctic islands: Baffin, Devon, Ellesmere, Axel Heiberg, Parry islands (Bathurst, Eglington, Ellef Ringnes, Loughead, Melville, Prince Patrick), Banks, Victoria, Somerset, Southampton (Nottingham and Digges).
Northern hemisphere distribution. Circumpolar. Northern Fennoscandian, KaninPechora, Svalbard Franz Joseph Land, Polar Ural Novaya Zemlya, YamalGydan, Taimyr Severnaya Zemlya, AnabarOlenyok, Kharaulakh, YanaKolyma, West Chukotka, Wrangel Island, South Chukotka, East Chukotka, West Alaska, North Alaska Yukon, Central Canada, Labrador Hudson Bay, Ellesmere Land Peary Land, West Greenland, East Greenland.
Illustrations. • Habitat. Yellow flowers in the foreground, R.J. Soreng and L.J. Gillespie in background. Plants 14 cm tall, growing in water. Nunavut, Axel Heiberg Island, large valley along upper Bukken River, 80°32'N, 92°22'W, 4 August, 1999. L.J. Gillespie 6620, L.L. Consaul and R.J. Soreng. CAN. • Baffin habitat. Yellow flowers near the marker and on the left-hand side of a snow patch runoff. Nunavut, Baffin Island, Iqaluit. Aiken and LeBlanc 04–016. CAN 586489. • Close-up of plants in snow patch. Plants 5–7 cm high growing between the markers in a snow patch. Nunavut, Baffin Island, Iqaluit. 6 July, 2004. Aiken and LeBlanc 04–016. CAN 586489. • Habitat: Ogac Lake. Yellow flowers between the markers. Plants common in this recently exposed snow patch. Nunavut, Baffin Island, Ogac Lake. 12 July, 2004. Aiken and LeBlanc 04–033a. CAN 586504. • Habitat. Plants with fading white petals to the right of the marker. Nunavut, Baffin Island, Apex. Aiken and Iles 02–065. CAN. Scale bar in cm. • Sepal hairs seen in bud. Flower bud showing sepals with sparse black hairs, surrounded by leaves with small hydathodes on the tips. Nunavut, Baffin Island, Ogac Lake. Aiken and LeBlanc 04–033a. CAN 585604. • Hairs on sepals. Flowers turned over to show the brown hairs on the sepals. Aiken and LeBlanc 04–016. CAN 586489. • Close-up of flowers. Flowers with bright yellow 'petals' and dark-haired 'sepals'. Alaska, Berring Land Bridge Preserve, Shishmaref Inlet, east of Cowpack River. August, 2001. Photograph by H. Solstad. • Close-up of petals and hydathodes. Note leaves with hydathodes, visible at 10x but not easily seen by the naked eye, yellow petals with forking veins, numerous anthers and free carpels with pale yellow sessile stigmas. Nunavut, Baffin Island, Iqaluit. 24 July, 2005. Photograph Kathy Thornhill. • Close-up of plant with flowers. Left, young flower with yellow petals. Right, plant going to seed. Note that the petals are fading white. Nunavut, Baffin Island, Apex. Aiken and Iles 02–065. CAN. • Close-up of plant going to seed. Plants with shiny dark green leaves and petals that have faded to white as plants go to seed. Nunavut, Baffin Island, Apex. Aiken and Iles 02–065. CAN. • Close-up of flowers. Flowers with the remains of the sepals covered in short brown hairs, five petals that were yellow but are fading to white, the remains of dehisced anthers, and the gynoecium of separate carpels beginning to ripen as achenes. Nunavut, Baffin Island, Apex. Aiken and Iles 02–065. CAN. • Close-up of flower. Fly resting on a flower that is beginning to set fruit. Aiken 05–068. CAN 586940. • Herbarium specimen. Relatively compact flowering plant. Nunavut, Baffin Island, Frobisher Bay, Yorke Island. 2 August, 1937. V.C. Wynne-Edwards. CAN 56035. • Close-up of flowering plant. Fruiting plant with tufted base, divided leaves with long petioles, a flower showing densely hairy sepals and a fruit borne on an elongated receptacle. Drawing by Mrs. S. Bergh and Mrs. L. Barstad based on herbarium specimen. Svalbard, Oscar II Land, Kapp Boheman, bay inside outtermost promitory. 30 August, 1924. J. Lid. With permission of the Botanical Museum, University of Oslo, Norway. • Close-up of plants in fruit. Fruiting plants growing near marker. Note leaves mainly basal. Nunavut, Baffin Island, Sylvia Grinnell Park. 1 August, 2005. Aiken 05–068. CAN. 586940. • Close-up of plants in fruit. Fruiting plants with elongated receptacles growing under a rock ledge along the east coast of Iqaluit. Nunavut, Baffin Island. 23 July, 1982, J.M. Gillett 19003. CAN. • Arctic Island Distribution.
This publication is available on the internet (posted May 2011) and on CD-ROM (published in 2007). These versions are identical in content, except that the errata page for CD-ROM is accessible on the main index page of the web version.
Recommended citation for the web-based version of this publication: Aiken, S.G., Dallwitz, M.J., Consaul, L.L., McJannet, C.L., Boles, R.L., Argus, G.W., Gillett, J.M., Scott, P.J., Elven, R., LeBlanc, M.C., Gillespie, L.J., Brysting, A.K., Solstad, H., and Harris, J.G. 2007. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. NRC Research Press, National Research Council of Canada, Ottawa. http://nature.ca/aaflora/data, accessed on DATE.
Recommended citation for the CD-ROM version of this publication: Aiken, S.G., Dallwitz, M.J., Consaul, L.L., McJannet, C.L., Boles, R.L., Argus, G.W., Gillett, J.M., Scott, P.J., Elven, R., LeBlanc, M.C., Gillespie, L.J., Brysting, A.K., Solstad, H., and Harris, J.G. 2007. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. [CD-ROM] NRC Research Press, National Research Council of Canada, Ottawa..