Flora of the Canadian Arctic Archipelago
English: Marsh cinquefoil,
French: Commaret des marais, potentille pallustre.
Rosaceae, Rose family.
Published in Sp. Pl. 502. 1753.
Type: Described from Europe, selected by Soják, in Jarvis et al., Regnum Veget. 127: 36. 1993. Lectotype: BM: Clifford Herbarium: 195. Comarum No. 1
Synonymy. Potentilla palustris (L.) Scop., Fl. Carniol., ed. 2, 1: 359. 1771.
Comarum arcticum Gand., Bull. Soc. Bot. France, 56: 533. 1909.
Vegetative morphology. Plants 4–10(–18) cm high; perennial herbs; not caespitose. Only fibrous roots present. Ground level or underground stems horizontal; rhizomatous; elongate; 2–4 mm wide. Caudex absent. Aerial stems developed (as branches from a horizontal stem); decumbent. Leaves present; distributed along the stems; alternate; dying annually and non-persistent (petioles and stipules marcescent). Stipules present; (10–)12–18(–25) mm long; (1–)1.5–3(–4) mm wide; not sheathing; pink or reddish; glabrous, or hairy; short-silky (rarely with a few scattered hairs); apex acute. Petioles 15–23(–30) mm long (often much larger further south); hairy, or glabrescent; short-silky, or long-silky (about 0.5 mm long). Petiole hairs shorter than the diameter of the petiole; appressed; straight; smooth. Leaf blades compound. Blades 15–30 mm long (often much longer further south), 25–50 mm wide (often much wider further south), veins palmate (leaflet veins pinnate). Blade adaxial surface glabrous. Blade abaxial surface glaucous, glabrescent or hairy, hairs short-silky (very short hairs), hairs sparse, hairs white, hairs straight, hairs appressed. Blade margins serrate, with non-glandular hairs (appressed, sometimes the only hairs on the blade), with 3–10 teeth on each side of the blade, with teeth all around the blade or toward the apex; degree of incision 20–25%; apices rounded, or retuse. Leaflet arrangement pinnate (sometime appearing digitate, leaflets divergent). Leaflets 5(–7); 15–30 mm long (longer further south); 10–20 mm wide (broader further south); elliptic, or obovate; veins conspicuous (on both surfaces). Apical leaflet base not distinctly stipitate.
Reproductive morphology. Flowering stems with leaves (similar in size to the basal leaves). Flowering stems hairy. Flowering stems short-silky, or pilose. Flowering stem hairs simple; shorter than the diameter of the flowering stem; white or translucent; glandular hairs present. Flowers solitary (in northern plants), or in inflorescences (further south). Inflorescences cymose; lateral; diffuse; elongating as the fruit matures. Pedicels present. Flowers per inflorescence 1(–10) (one in the Arctic Archipelago plants, often 5–10 on more southern plants); large. Sepals conventional. Epicalyx present. Epicalyx segments 2–4 mm long. Epicalyx segments 0.5–1 mm wide. Epicalyx segments shorter than the calyx segments (much shorter). Epicalyx segments narrower than the calyx segments (very much narrower). Sepals 5; free; (3–)3.5–4.5(–5) mm long; (5–)7–12(–14) mm wide; purple (brownish); accrescent. Calyx without sessile glands (but with stalked glands); hairy. Calyx hairs short-silky; glandular; white or translucent. Petals conventional; free; 5; pink, or purple; without contrasting markings; elliptic (acute to acuminate); unlobed; (2.5–)3–6(–8) mm long; (1–)1.5–2.5(–3) mm wide. Stamens 15–25(–30); stamen filaments glabrous; free of the corolla. Anthers purple (dark); ellipsoid; 1–1.2 mm long. Ovary superior; carpels 40–60; apocarpous. Styles 0.9–1.2 mm long; straight; basal portion smooth. Ovules per ovary 1. Fruit with calyx persisting; dry; an aggregate of achenes; ovoid; brown (pale); 8–12 mm long; 10–15 mm wide; glabrous; surface appearing veinless; indehiscent.
Chromosome information. 2n = 28, or 35, or 42 (frequently), or 56, or 60–62–64.
2n (4x) = 28. Wulff (1937, central Europe); Ehrenberg (1945, Sweden); Löve and Löve (1956, Iceland); Kartashova et al. (1974, Siberia);
2n (5x) = 35-36. Lövkvist, in Weimarck (1963, Sweden); Taylor and Mulligan (1968, western Canada); Zhukova and Petrovsky (1977, northeastern Asia, 2n = 36, probably aneuploid); Al-Bermani et al. (1993, western Europe);
2n (6x) = 42. Jørgensen et al. (1958, Greenland); Sokolovskaya (1960b, 1963, 1965, 1970, 1972); Sokolovskaya and Strelkova (1960, 1962); Lövkvist, in Weimarck (1963, Sweden); Löve and Solbrig (1965) Löve and Löve (1982a, Arctic Canada; 1982c, eastern Canada); Löve and Ritchie (1966, northern Canada); Zhukova (1966, 1967a, 1969, northeastern Asia; 1980, southern Chukotka); Knaben and Engelskjøn (1967, southern and northern Norway); Johnson and Packer (1968, northwestern Alaska); Laane (1969a, Norway); Löve (1970a); Asker (1971); Zhukova and Tikhonova (1971, Chukotka); Krogulevich (1976a, 1978, 1984, southern and northern Siberia); Zhukova and Petrovsky (1976, western Chukotka); Zhukova et al. (1977, northeastern Asia); Engelskjøn (1979, Norway); Yurtsev and Zhukova (1982, northern Siberia); Lövkvist and Hultgård (1999, southern and northern Sweden); Gervais (1997a, 1999, eastern Canada). Numerous more southern counts;
2n (8x) = 56. Laane and Lie (1985, Norway);
2n (9x) = 60-62–64. Sokolovskaya and Strelkova (1941, northern Russia, 2n = 62–64); Zhukova (1967a, northeastern Asia, 2n = 60, probably aneuploid); Dempsey et al. (1994, western Europe, 2n = 64). Supposed basic chromosome number of family 7.
Ploidy levels recorded 4x, 5x, 6x, 9x(?).
Ecology and habitat. Substrates: around the margins of ponds, marshes; aquatic, imperfectly drained moist areas; sand, silt, clay, moss; with high organic content, peat; acidic, or non-calcareous.
North American distribution. A mainly boreal and Low Arctic species that only reaches the Arctic islands at two known sites on Baffin Island. It is also found several places on the mainland adjacent to Victoria Island. Alaska, Yukon, continental Northwest Territories, Nunavut Islands, continental Nunavut, northern Quebec, Labrador. Range in the Canadian Arctic Archipelago limited. Rare. Boreal and Low Arctic. Arctic islands: Baffin.
Northern hemisphere distribution. Circumpolar, or circumboreal. Northern Iceland, Northern Fennoscandian, KaninPechora, Polar Ural Novaya Zemlya, YamalGydan, Taimyr Severnaya Zemlya, AnabarOlenyok, Kharaulakh, YanaKolyma, West Chukotka, South Chukotka, East Chukotka, West Alaska, North Alaska Yukon, Central Canada, Labrador Hudson Bay, West Greenland, East Greenland.
General notes. The choice between recognising this as a species of Potentilla or placing it in its own genus Comarum is largely a matter of how widely or narrowly Potentilla should be circumscribed. If Comarum is split off, it also necessitates recognition of Anserina and Dasiphora as separate genera, whereas an inclusion of these in Potentilla should be followed by an inclusion of, for example, Fragaria and Sibbaldia. Elven et al. (2003) preferred to accept Comarum as a separate genus.
Illustrations. • Habitat. Plants growing in Carex aquatilis meadow. Manitoba, Churchill, Bird Cove. 23 July, 2001. Aiken and Brysting 01–013. • Close-up of plant. Centre, the flower bud has broad calyx segments folded around the opening flower and narrow, extended epicalyx segments. Upper flower, both epicalyx and calyx segments are spreading. Manitoba, Churchill, Bird Cove. 23 July, 2001. Aiken and Brysting 01–013. • Plant habit. Note leaves composed 5 to 7 leaflets with serrate blade margins. Alaska, Kotzebue. 19 July, 1962. Mildred and Raymond R. Wood. CMN Photo library S78–803. Photograph by R. Wood. • Close-up of flowers. Flowers with narrow green epicalyx segments, broad apiculate purplish calyx segments, much smaller red petals that alternate with the sepals, two whorls of deep red pre-anthesis anthers, and a brownish centre with developing carpels. Aiken and Brysting 01–013. • Close-up of flower. Flower approximately 1.5 cm in diameter, with narrow green epicalyx segments, broad apiculate dark red purplish calyx segments, much smaller red petals that alternate with the sepals, two whorls of deep red pre-anthesis anthers, and a brownish centre with developing carpels. Aiken and Brysting 01–013. • 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..