Rumex arcticus Trautv.
Arctic Dock Arctic Sourdock (Porsild 1950).
Polygonaceae, buckwheat family.
Reise in den Äussersten Norden und Ostenorthern Siberiairiens 1: 29. 1847.
Rumex aquaticus subsp. arcticus (Trautv.) Hiitonen
Type: Described from Siberia: "Taimyr R. 74 1/4° and 75°N".
No synonymy for var. arcticus in Kartesz (1994).
Vegetative morphology. Plants perennial herbs; 10–80 cm high; glabrous with erect, unbranched or branching stems from a thick, fleshy caudex. Taproot present. Roots red-brown. Caudex present (stout, not elongate), or absent. Ground-level or under-ground stems not developed horizontally or vertically. Aerial stems erect; circular or oval in cross-section; glabrous. Branches not glaucous (deep red). Leaves distributed along the stems, or in a basal tuft (long-petioled basal leaves from which arises the stout, leafy stem); alternate; marcescent. Stipules present; scale-like (modified as ocreae, which are tubular sheaths formed from two fused stipules); 5–15 mm long; 3–8 mm wide (tubular width measured, width depends on width of stem); sheathing; brown. Stipules glabrous. Stipules apex truncate. Petioles 1–13 mm long (short on cauline leaves, long on basal leaves); unwinged; glandular dots at the base of the leaf absent; glabrous. Sheaths persisting; forming a conspicuous build up at the base of the plant; brown; with the margins fused to the apex; glabrous. Leaf blade bases obtuse, or acute. Blades (2–)4–12(–15) mm long; 1–4 mm wide. Blades spreading; oblong, or elliptic, or lanceolate, or ovate; flat; veins pinnate. Blades secondary veins flat on adaxial surface, protruding on abaxial surface; arising along midrib. Blades adaxial surface glabrous. Blades abaxial surface glabrous. Leaf apices acute.
Reproductive morphology. Flowering stems present. Flowering stems conspicuously taller than the leaves; with leaves; glabrous. Inflorescence paniculate; dense; linear, or lanceolate, or ovate; 5–15 cm long; 25–60 mm wide; main axis glabrous; main branches angle of divergence less than 30 degrees, or 30–60 degrees. Pedicels present, or absent (at the same node of the inflorescence some flowers are sessile and some pedicelled); glabrous. Pedicels bract leaves 0.5–1 mm long (ochreoles); 1–1.5 mm wide. Flowers per inflorescence 100–300 (or more); small, less than 5 mm in diameter or length. Calyx present. Calyx base widely angled. Calyx sepals 3; free (at the apex), or fused; 2–3.5 mm long; 0.5–1 mm wide (approximately). Calyx purple, or red, or black (deep red appearing black); rotate; 3-lobed; glabrous. Calyx teeth 2–3 mm; without or with few glandular verrucae. Petals present; free; 3; red, or pink; ovate; unlobed; 3–7 mm long; 1–2 mm wide. Stamens present and probably functional. Stamens 3–5 (?); filaments glabrous. Anthers axis straight; 0.5–0.7 mm long. Gynoecia superior. Carpels syncarpous; 3. Styles 2; free; 0.2–0.6 mm long. Stigmas per style 1; plate shaped (flat or cup or funnel-shaped, composed of a collection of radiating "tentacles"). Placentation basal. Ovules 1. Fruit stalked. Fruit dry; an achene; ovoid; indehiscent. Fruit 3–4 mm long (more when more ripe??); 1.2–2 mm wide; brown; surface appearing veinless. Achenes trigonous (but compressed).
Chromosome information. 2n = 40–200. 40
(4x). - Knaben (1968 central Alaska); Mulligan and Porsild (1969b Yukon);
Mulligan et al. (1972a); Mulligan and Frankton (1972); Löve and Löve
(1975a, as 'kamtschadalus'); Dawe and Murray (1981 central Alaska).
80 (8x). - Packer and McPherson (1974 northern Alaska); Dawe
and Murray (1981a/b western Alaska, three counts); Zhukova (1982 north eastern
Asia); Löve (1986b, as 'kamtschadalus').
120
(12x). - Ichikawa et al. (1971); Mulligan and Frankton (1972); Löve
and Löve (1975a); Zhukova (1980, 1982 north eastern Asia); Löve
(1986b).
150 (15x). - Zhukova (1965a eastern Chukotka, 2n =
150+); Zhukova et al. (1973 northern and north eastern Asia 2n = 150+);
Krogulevich (1976 northern Siberia).
170 (17x). - Johnson and Packer
(1968 northwestern Alaska ).
200 (20x). - Löve and Löve
(1948, 2n = c.200); Sokolovskaya (1968 north eastern Asia, Koryak, as
'kamtschadalus'!). Sokolovskaya's count on Komarov's
'kamtschadalus'. Ploidy levels recorded
4x&8&12&15&17&20.
Distribution. Northern hemisphere distribution: amphi-Beringian (broadly); Canada, United States, Eurasia. Alaska, Yukon, Northwest Territories Islands, Continental Nunavut. Arctic Islands: Banks.
Ecology and habitat. Substrates: lake shores (beach), seashores (on sandy beaches); moderately well drained areas; sand.
Indigenous knowledge. The mildly acid leaves of young stems may be eaten raw as a salad, or cooked as spinach. (Porsild 1950).
Illustrations. • Plant in habitat. Reddish-coloured Rumex arcticus plant about 70 cm tall, in fruit, among the green Leymus mollis. In sand at coast, Anderson River Delta, NWT, about 5 km SE of Krekovick Landing. 69°40.3'N, 128°52.4'W. 6 Aug. 1997, L.L. Consaul 1145 and L.J. Gillespie. CAN. • Plant in habitat. Rumex arcticus plants to 1 metre tall in a lakeshore habitat. Unnamed lake in Mackenzie River delta, NWT, 18 km SE of Swimming Point. 69°1.6'N, 134°0'W, 14 August 1997. L.L. Consaul 1159 and L.J. Gillespie. CAN. • Plant habit. Rumex arcticus: plant habit. Photo taken near coastguard station at Tuktoyaktuk, N.W.T. Plants growing on a sandy beach, July 21, 1981, J.M. Gillett 18739. • Close-up of plant. Plant in early fruiting stage. In wetland with Arctophila and Carex. Canada: Yukon Terr., Buckland Hills N of British Mts. Aug. 1999. Photographed by R.Elven. Voucher in HbO. • Close-up of plant. Rumex arcticus plants to 1 metre tall in a lakeshore habitat. Unnamed lake in Mackenzie River delta, 18 km SE of Swimming Point. 69°1.6'N, 134°0'W, 14 August 1997. L.L. Consaul 1159 and L.J. Gillespie. CAN. • Close-up of inflorescence. Flowers and developing fruit of Rumex arcticus inflorescence. Unnamed lake in Mackenzie River delta, 18 km SE of Swimming Point. 69°1.6'N, 134°0'W, 14 August 1997. L.L. Consaul 1159 and L.J. Gillespie. CAN. • Arctic Island distribution.
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).
