Minuartia rossii (R. Br. ex Richardson) Graebn.
Caryophyllaceae, pink family.
Graebner in Ascherson and Graebner, Syn. Mitteleur. Fl. 5, 1: 772. 1918.
Arenaria rossii R.Br. ex Richardson, Bot. App. 738. 1823.
Alsinanthe rossii (R.Br. ex Richardson) Á. and D. Löve
Type: Described from "British North America" [probably Kent Peninsula], 1819–1822, leg. Richardson (BM).
Alsinanthe rossii (R.Br. ex Richardson) Á. and D. Löve
Alsinopsis rossii (R.Br. ex Richardson) Rydb.
Arenaria
rossii R.Br. ex Richardson
Arenaria rossii var. daethiana
Polunin
Minuartia rolfii Nannf.
Vegetative morphology. Plants perennial herbs; 1–3 cm high; low, cushion-like or matted; dark green but often purplish; vegetatively proliferating by bulbils or fragmentation (terminal buds). Taproot present. Caudex absent. Ground-level or under-ground stems horizontal, or not developed horizontally or vertically; stoloniferous; compact; 0.5–1.2 mm wide. Aerial stems ascending, or decumbent; glabrous. Leaves distributed along the stems; opposite; marcescent. Petioles absent. Leaf blade bases cuneate. Blades 2–3(–5) mm long; 0.5–0.7(–1.2) mm wide. Blades spreading; herbaceous; elliptic; flat, or folded; appearing single-veined, or with inconspicuous veins. Blades adaxial surface dull; glabrous. Blades abaxial surface glabrous. Blade margins glabrous. Leaf apices obtuse.
Reproductive morphology. Flowering stems with leaves; glabrous. Flowering stems glandular hairs absent. Flowers solitary; small, less than 5 mm in diameter or length. Calyx sepals 5; free; 1.5–2.5 mm long (with one vein, oblong-ovate, obtuse to acuminate, and keeled). Calyx purple (soon pale yellowish); herbaceous and scarious; glabrous. Petals free; longer than the calyx; 5; white; obovate (narrowly), or spatulate; unlobed; 2–3.5 mm long. Stamens 10; filaments glabrous. Anthers yellow; ellipsoid; 0.2–0.5 mm long. Gynoecia superior. Carpels syncarpous; 3. Ovaries ovate; glabrous. Styles 3; free; 0.4–0.9 mm long. Stigmas per style 1. Placentation free central. Ovules 10–12. Fruit with calyx persisting; dry; a capsule; ovoid, or elongate-cylindrical; dehiscent; opening with teeth at the top of the capsule; teeth 3. Fruit 1.5–2 mm long (shorter than or as long as the sepals); 1–1.2 mm wide; straw coloured; surface appearing veinless. Seeds several; 0.2–0.6 mm long; brown; with surfaces rugose.
Chromosome information. 2n = 58, 60. 58. - Zhukova (1966
Chukotka); Zhukova and Petrovsky (1972 Chukotka); Zhukova et al. (1973
Chukotka).
60 (4x). - Löve and Löve (1975b northern
Canada: Melville Island, 1982 northern Canada: Churchill); Wolf et al. (1979a
northern Canada: Cornwallis Island, Alaska: Prudhoe Bay). Ploidy levels recorded
4x.
Distribution. Northern hemisphere distribution: North American (mainly but extending into the Russian Far East and Svalbard); Greenland, Canada, United States, Eurasia. Yukon, Northwest Territories Islands, Continental Northwest Territories, Nunavut Islands, Continental Nunavut. High arctic. Range in the Canadian Arctic Archipelago limited. Uncommon. Arctic Islands: Baffin, Devon, Ellesmere, Axel Heiberg, Parry Islands, Cornwallis, Banks, Victoria, Prince of Wales, Somerset, King William, Southampton (Akpatok, Prince Charles, King Christian, Ellef Ringnes, and Eglinton Islands). Wrangle Island, High Arctic North America, Greenland, Spitzbergin.
Ecology and habitat. Substrates: along streams, slopes; on seepage slopes, or moderately well drained areas; calcareous; gravel, sand; with low organic content.
Notes. Minuartia rossii rarely flowers and relies almost
exclusively on vegetative reproduction via bulbils (axillary or terminal leaf
buds), which are easily detached and spread by wind or running water and root
very rapidly (Wolf et al. 1979a). Flowering plants occur in fairly dry
sites, whereas reproduction by bulbils may dominate in wet, late sites. In
Svalbard, ripe capsules and seeds are very rare and are formed only in
favourable years (Elven and Elvebakk 1996). Porsild (1955) noted that M.
rossii flowers abundantly in favorable years, particularly in more southerly
regions. This observation is confirmed by Wolf et al. (1979a).
Minuartia rossii is closely related to M. stricta. Nannfeldt
(1954) studied the relationship between these two taxa and recognised both as
species.
Illustrations. • Plant habitat. Isolated cushion-like plant growing in an area with less than 5% vegetation cover. Nunavut, Ellesmere Island, Scoresby Bay, 79°53'N, 71°33'W. Aiken 98–025. CAN. Photograph by Mollie MacCormac. • Plant in habitat. This almost exclusively, polster-shaped or straggling (as here) arctic plant is normally non-flowering but produced bulbils in the shoot apices; may, however, flower in favourable sites and years even in high-arctic Svalbard. Norway: Svalbard, Dickson Land, Odindalen Valley. Aug. 1996. Photo: R.Elven. Voucher in HbO. • Close-up of plant. Flowers solitary; petals white, obovate or spatulate, unlobed; 10 stamens and 3 stigmas. Nunavut, Ellesmere Island, Scoresby Bay, 79°53'N, 71°33'W. Aiken 98–025. CAN. Photograph by Mollie MacCormac. • Drawings of flowers. Drawing by Mrs S. Bergh and Mrs L. Barstad based on a collection from Svalbard, Ny-Friesland. Sheet currently on loan to Sweden. With permission of the Botanical Museum, University of Oslo, Norway. • Distribution map.
Cite this publication as: ‘S.G. Aiken, M.J. Dallwitz, L.L. Consaul, C.L. McJannet, L.J. Gillespie, R.L. Boles, G.W. Argus, J.M. Gillett, P.J. Scott, R. Elven, M.C. LeBlanc, A.K. Brysting and H. Solstad. 1999 onwards. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 29th April 2003. http://www.mun.ca/biology/delta/arcticf/’. Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993, 1995, 2000) should also be cited (see References).
