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

Diapensiaceae Lindley

English: Diapensia.

Diapensiaceae, Diapensia family.

Published in Sp. Pl. 141. 1753.

Vegetative morphology. Plants 1–5(–8) cm high; shrubs (small plants easily misinterpreted as herbs); dwarf shrubs. Roots pallid-brown. Aerial stems branching from a tap at or near ground level into two or more branches; erect (branching beneath the recent season's leaves in older tussocks with an accumulation of duff amongst the branches), or prostrate (occasionally, as when a plant is growing under a rock and sends a stem underneath which develops a small cushion at the tip). Leaves distributed along the stems; whorled (in dense ascending, compact whorls); persistent. Petioles absent. Leaf blades simple (yellowish green in upper portion, pale at the base in summer; dark burgundy in winter). Leaf blade bases truncate. Blades 5–15(–20) mm long, 0.5–3 mm wide, divaricate, oblong or spatulate, flat, appearing single-veined. Blade adaxial surface shiny, glabrous. Blade abaxial surface glabrous. Blade margins slightly revolute. Blade margins entire, with glandular hairs; apices obtuse, or rounded.

Reproductive morphology. Flowering stems without leaves (The illustration in Porsild (1957) and Porsild and Cody (1980) shows leaves on the scape, but we have not been able to confirm the presence of such leaves (Peter Scott, personal communication, 1999)). Flowers solitary (or 2–3). Involucral bracts present. Flowers medium-sized. Sepals conventional; 5; free; 2–4 mm long; 5–6 mm wide; green (yellowish or pinkish); leathery (slightly). Calyx glabrous. Petals conventional; fused (for half their length; corolla appearing deeply lobed); 5; white (or cream or rose, or light pink petals are known for this species from Newfoundland and for subsp. obovata from Alaska and Japan); 0.8–1.4 mm long. Corolla tubular (fused base of the petals), or rotate (free petal lobes); 5-lobed. Stamens 5 (alternate with the petal lobes); stamen filaments glabrous; fused to the corolla (between each petal). Anthers yellow; 0.7–0.9 mm long (entrose anthers, on broad, flat filaments). Nectaries absent. Ovary superior; carpels 3; syncarpous. Styles 1. Stigmas per ovary 1 (sometimes with 3 lobes at the apex). Ovules per ovary many approximately 240. Fruit stalked; with calyx persisting; dry; a capsule; ovoid; brown, or red (pale pinkish or yellowish); 2–3 mm long; 1–2 mm wide; dehiscent. Seeds 25–130; 0.7–1.1 mm long (tetrahedral in shape); brown (pale cream under a conspicuous tan brown reticulation on the surfaces); surfaces ridged (seedlings rarely seen).


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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