Flora of the Canadian Arctic Archipelago

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S.G. Aiken, M.J. Dallwitz, L.L. Consaul, C.L. McJannet, R.L. Boles, G.W. Argus, J.M. Gillett, P.J. Scott, R. Elven, M.C. LeBlanc, L.J. Gillespie, A.K. Brysting, H. Solstad, and J.G. Harris

Parrya arctica R. Br.

Brassicaceae (Cruciferae), Draba family.

Published in Chlor. Melvill. 11. 1823.

Type: Canada: Nunavut: Melville Island., leg. Capt. Parry (fruiting specimen), J. Ross (flowering specimen). Holotype: BM?

Synonymy. Parrya arctica R. Br. f. albiflora B. Boivin ex Cody, Canad. Field-Naturalist 67: 42. 1953.

Vegetative morphology. Plants 1–10 cm high; perennial herbs; caespitose. Taproot present. Caudex present (stout, 7–20 mm in diameter). Aerial stems erect. Leaves mainly basal; alternate; dying annually and non-persistent. Petioles absent. Leaf blades simple. Leaf blade bases attenuate. Blades (7–)12–30 mm long, 3–5 mm wide, lanceolate or ovate or obovate, appearing single-veined. Blade adaxial surface glabrous. Blade abaxial surface glabrous. Blades not lobed. Blade margins entire or dentate (often dentate at the apex), glabrous. Hydathodes absent. Blade apices obtuse.

Reproductive morphology. Plants bisexual. Flowering stems two or more per plant; about as high as the leaves; without leaves. Inflorescences racemose. Flowers per inflorescence 6–12; medium-sized; radially symmetrical (actinomorphic). Sepals conventional; 4; free; 2.5–3 mm wide; green and purple; herbaceous (scarious margin). Calyx glabrous. Petals conventional; free; 4; white, or purple (on Banks and Victoria Islands, the purple- and white-flowered forms are equally common and often grow intermingled (Porsild and Cody 1980); without contrasting markings; obovate; unlobed; 7–10 mm long. Stamens 6; stamen filaments markedly unequal in length; stamen filaments glabrous; free of the corolla. Anthers yellow; 0.9–1.1 mm long. Ovary superior; carpels 2; syncarpous. Ovaries glabrous. Styles 1; 0.1 mm long. Stigmas per ovary 1. Placentation parietal. Ovules per ovary 6–8. Fruit stalk 9–18 mm long; dry; a silique; ovoid (strongly keeled when fresh, often constricted between seeds); purple; 6–25 mm long; 3–6 mm wide; glabrous; surface appearing veinless (obscurely veined); dehiscent; shedding the outer walls to expose a thin inner wall, with the seeds attached at the margins on either side. Styles persisting in fruit 0.2–0.3 mm long. Seeds (4–)6–8; 2–3 mm long; brown; surfaces winged (yellow membranous rims).

Chromosome information. 2n = 14.

2n (2x) = 14. Mosquin and Hayley (1966, northern Canada); Hedberg (1967, northern Canada, as P. arctica?).

2n (3x) = about 21. Mosquin and Hayley (1966, northern Canada); Mulligan (unpublished? northern Canada);

In addition to the two diploid counts referred to above, Löve and Löve (1975) listed six diploid (2n = 14) counts under this name from areas where it is not now generally recognised as occurring from central Alaska (Knaben 1968) and northeastern Asia (Zhukova and Petrovsky 1971, 1972; Yurtsev and Zhukova 1972). The reason is that Löve and Löve synonymised P. arctica with P. nudicaulis subsp. septentrionalis, obviously to get a better 'fit' between ploidy levels and species boundaries. In their opinion, Parrya nudicaulis s.s. is tetraploid. This synonymisation is not acceptable.

Ploidy levels recorded 2x/3x.

Ecology and habitat. Substrates: wet meadows, hummocks, river terraces, slopes, ridges; imperfectly drained moist areas (creek deltas), seepage slopes, dry; gravel, sand, silt, clay; calcareous. Flowers are not strongly scented, although some writers report a faint scent of lilacs. The production of scent is often temperature-dependent (Burt 2000).

North American distribution. Northwest Territories Islands, continental Northwest Territories, Nunavut Islands, continental Nunavut. Range in the Canadian Arctic Archipelago widespread. Common. High Arctic. Arctic islands: Parry islands (Bathurst, Cameron, Melville, and Prince Patrick), Cornwallis, Banks, Victoria, Prince of Wales, Somerset, King William.

Northern hemisphere distribution. North American. Central Canada, Labrador – Hudson Bay, Ellesmere Land – Peary Land.

General notes. Material from an isolated site in Herschel Island, North Yukon, has been reinvestigated and found to have been misidentified (Mulligan, personal communication, Sept. 2002).

Illustrations. • Colour forms growing together. Adjacent plants, one with white, the other with purple/pink flowers, growing in dry sandy gravel. N.W.T., Banks Island, Aulavik National Park. 11 July, 1999. Aiken 99–042. CAN. Scale bar in cm. • Close-up of adjacent plants. Adjacent plants, one with white, the other with purple flowers. N.W.T., Banks Island, Aulavik National Park. 11 July, 1999. Aiken 99–042. CAN. Scale bar in cm. • Plant habit. Plants growing in a sheltered gully. This species may have white or pinkish purple flowers. N.W.T., Banks Island, Sachs Harbour. 27 July, 1981. J.M. Gillett 18860. CAN. • Close-up of plant. Plants approximately 5 cm high, with purple flowers growing with a sedge. Banks Island, Aulavik National Park, near Green Cabin. 1 July, 1999. Aiken 99–010. CAN. Scale bar in cm. • Close-up of plant with white flowers. Isolated plant with white flowers and dentate blade margins growing in a sand dune. Banks Island, Aulavik National Park. 10 July, 1999. Aiken 99–043. CAN. • Close-up of white flower. Flower with four greenish sepals with white tips, four white spatulate petals green at the claw, six anthers, and one stigma. N.W.T., Banks Island, Aulavik National Park. 10 July, 1999. Aiken 99–043. CAN. • Close-up of flower. Whitish petals that have faint pink lines, a whorl of four anthers opposite the petals that have shed pollen and a whorl of two pre-anthesis anthers that alternate with the petals. Note the central stigma. Banks Island, Aulavik National Park. 11 July, 1999. Aiken 99–042. CAN. • Close-up of plant in fruit. Fruits distinctly shorter and fatter than those of Erysimum. Nunavut, Cornwallis Island. CAN 259191. • Close-up of fruit. Note the somewhat wavy and lumpy outline to the fruits, a distinguishing character state for this species. Nunavut, Cornwallis Island. CAN 2591591. • 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.

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