Flora of the Canadian Arctic Archipelago
English: Foliolose saxifrage, grained saxifrage,
French: Saxifrage à bulbilles,
Saxifragaceae, Saxifrage family.
Published in Chloris Melvill. 17. 1823.
Type: Canada: Melville Island, Cap. Nels., [1819–1820], leg. M.J. Ross. Holotype: BM.
Synonymy. Spatularia foliolosa (R.Br.) Small, N. Amer. Fl. 22, 2: 149. 1905.
Saxifraga stellaris var. comosa Retz., Fl. Scand. Prodr. 79. 1779.
Saxifraga stellaris L. var. multiflora Hultén, Ark. Bot., ser. 2, 7, 1: 68. 1968.
Vegetative morphology. Plants 3–15(–25) cm high; perennial herbs; caespitose; sometimes vegetatively proliferating by bulbils on stems or leaves. Ground level or underground stems absent (Porsild (1957) indicated that stolons ending in leafy rosettes occur, but this has not been confirmed). Caudex present (short, and often branching). Aerial stems erect. Leaves not heterophyllous; basal in a rosette; erect; alternate; marcescent (somewhat). Petioles absent. Leaf blades simple. Leaf blade bases truncate, or attenuate (slightly). Blades 10–25 mm long, 3–8 mm wide, oblanceolate or spatulate, flat, with inconspicuous veins. Blade adaxial surface glabrous. Blade abaxial surface glabrous. Blades not lobed. Blade margins serrate, with non-glandular hairs (sparse) or glabrous, with teeth toward the apex (3–7 teeth); apices acute, or obtuse.
Reproductive morphology. Flowering stems solitary; with leaves. Flowering stems hairy. Flowering stems pilose. Flowering stem hairs simple; shorter than the diameter of the flowering stem; white or translucent; glandular hairs present. Flowers in inflorescences. Inflorescences with bulbils (or small leafy buds that occur on the stems below the flowers); racemose, or paniculate; terminal (with or without more than one flower at the apex); 0–5 cm long. Pedicels present; with glandular hairs. Flowers per inflorescence 0–7; medium-sized. Sepals conventional; 5; free; 1–1.5 mm long; 1.5–2.2 mm wide; green, or purple. Calyx glabrous. Petals conventional; free; 5; white; with contrasting markings (usually with 2 yellow spots near the base); obovate; unlobed; 3.5–6(–7.5) mm long; 1.6–2 mm wide. Stamens 10. Anthers purple; 0.4–0.5 mm long. Nectaries present. Receptacle 0.5–0.9 mm high. Ovary superior; carpels 2; partly fused (more than half of their length). Ovaries glabrous. Placentation axile. Ovules per ovary 50–100 (approx.). Fruit with calyx persisting (reflexed); dry; a capsule; spherical (with 2 divergent carpel apices); purple; 3–5 mm long; 2–3.5 mm wide; dehiscent; splitting to the base into separate segments. Seeds 50–100 (approx.).
Chromosome information. 2n = 40, 48, 56, 64, and 66.
(2n) = 40. Zhukova et al. (1973, north and northeastern, Asia); Zhukova and Petrovsky (1987b, northeastern Asia); Devyatov et al. (1997, northeastern Asia);
(2n) = 48. Zhukova and Petrovsky (1987b, northeastern Asia);
(2n) = 56. Arwidsson (1938, northern Europe); Böcher (1938b, northern Europe); Flovik (1940, Svalbard); Sørensen and Westergaard, in Löve and Löve (1948, Greenland); Löve and Löve (1948, northern Europe; 1951, 1956, Iceland); Jørgensen et al. (1958, Greenland); Sokolovskaya (1958, 1962); Sokolovskaya and Strelkova (1960); Mosquin and Hayley (1966, northern Canada); Knaben and Engelskjøn (1967, northern Norway); Zhukova (1967a, northeastern Asia; 1980 southern Chukotka; 1982, northeastern Asia); Johnson and Packer (1968, northwestern Alaska); Krogulevich (1971, southern Siberia; 1976, northern Siberia; 1984, Siberia); Zhukova and Tikhonova (1973, Chukotka); Packer and McPherson (1974, northern Alaska); Zhukova and Petrovsky (1976, western Chukotka; 1987b, northeastern Asia); Hudson (1987, northeastern USA); Devyatov et al. (1997, northern Russia);
(2n) = 64. Harmsen (1939, Greenland); Löve and Löve (1948, not cited in 1975); Krogulevich (1971).
(2n) = 66. Löve and Löve (1948, not cited in 1975). These authors gave this species a uniform chromosome number of 2n = 56.
Taxon as an environmental indicator. The habit of the plant is an indication of the environment in which it is growing. The species is phenotypically plastic, varying from robust plants 30 cm high with numerous stems in favourable environments to delicate plants 8–10 cm high with few stems in harsh habitats. The northernmost record is Low Point, 83°06'N, on the north coast of Greenland. In Canada, it has been collected on Ward Hunt Island, 83°03'N (Canada).
Ecology and habitat. Substrates: imperfectly drained moist areas (often by the edge of small streams or beside ponds in wet tundra), moderately well-drained areas (on wet slopes); sand; with low organic content.
North American distribution. Elven (personal communication, 2005) noted that in his Eurasian and American experience, this is a specialist of wet, mostly calcareous sites, partly real marshes and mires, partly seepage. I have almost never seen it on "moderately well-drained areas". Aiken collected a specimen growing in sand on a river bank in Iqaluit, 2005. Alaska, Yukon, Northwest Territories Islands, continental Northwest Territories, Nunavut Islands, continental Nunavut, northern Quebec, Labrador. Range in the Canadian Arctic Archipelago widespread. Common. Arctic. Arctic islands: Baffin, Devon, Ellesmere, Axel Heiberg, Parry islands (Bathurst, Eglington, Mackenzie King, Melville, Prince Patrick), Cornwallis, Banks, Victoria, Prince of Wales, Somerset, King William, Southampton, Coats (Coburg, Armund and Ellef Ringnes, Meighen, Stefansson, Boothia and Melville peninsulas).
Northern hemisphere distribution. Circumpolar. Northern Iceland, 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.
General notes. This species belongs in the genus Micranthes, and will be treated as such in Volume 8 of Flora of North America (L. Brouillet, Université de Montréal, personal communication, 2006). The new combination by R.J. Gornall is forthcoming but has not yet been published.
Polunin (1940) recognised this taxon as wide-ranging latitudinally, and fairly common almost everywhere, growing chiefly on damp humus soil or among mosses. He observed that this species varies in its general robustness, from plants with many thick and much branched stems up to 30 cm in height. More commonly occurring plants are tiny rosettes supporting a single very slender unbranched stem only 8–10 cm high. The taxon was treated as S. stellaris var. comosa Retzius by Polunin (1940).
In the Arctic Archipelago, the flowers are replaced by an abundance of little bulbils, although two or three of the main branches may still bear terminal flowers. There is very often a single flower crowning the central axis, except on plants growing in extreme habitats.
This species is always gemmiferous, but sometimes with one apical flower, very rarely with several (Hultén's 'multiflora'). Some seed-set has been observed, but only once or twice in modern botanical history. It is certainly a fairly rare phenomenon. It has sometimes been hypothesised as a gemmiferous derivative from a hybrid involving S. stellaris, but the obvious closest now-living relative is the Asian S. redofskyi Adams (Elven, personal communication, 2005).
Molau (1992) discussed the occurrence of sexual reproduction in this species.
Illustrations. • Close-up of plants in habitat. Plants in bud and beginning to flower, growing in wet meadow with springy moss. Nunavut, Baffin Island, Iqaluit. 25 July, 1982. J.M. Gillett 19061. CAN. • Habit. Plants growing in wet sand in moss sedge meadow. Plant with a basal rosette of leaves, scapose flowering stems (i.e., without leaves on the stems) and inflorescences of several flowers. Nunavut, Baffin Island, Pond Inlet, 'Red Hills'. L.J. Gillespie 6053. CAN. • Inflorescence and bulblets. Flowering stem with numerous green bulblets (arrows) that fall off and may develop into new plants. Each stem has a single flower with white petals and a pink gynoecium. Nunavut, Baffin Island, Pond Inlet, 'Red Hills'. L.J. Gillespie 6053. CAN. • Close-up of flowers. Flowers with acute-tipped lanceolate white petals, which have two yellow spots towards the base. Left flower, anthers have been shed leaving stiff white filaments. Right flower has many anthers that are purple-red. The pink superior ovary is composed of two carpels that are fused to the top and can be seen as two short styles in the right-hand flower. L.J. Gillespie 6053. 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..