Flora of the Canadian Arctic Archipelago


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

Saxifraga tricuspidata Rothb.

English: Prickly saxifrage, three-toothed saxifrage,

French: Saxifrage à trois dents,

Inuktitut: Kakillarnaq (singular), kakillarnat (plural), tiinnguat, a'asaat; kakagutik, kakillanaqutik (Nunavik).

Saxifragaceae, Saxifrage family.

Published in Skr. Kiøbenhavnske Selsk. Lærd. Elsk. 10: 446. 1770.

Type: Greenland: [Grønland], 1739, leg. Egede. Egede Herbarium. Holotype: C.

Synonymy. Leptasea tricuspidata (Rottb.) Haw., Saxifr. Enum. 40. 1821.

Saxifraga tricuspidata Rottb. var. subintegrifolia Abrom., Bibl. Bot. 42, 2: 36. 1899.

Saxifraga tricuspidata Rottb. f. subintegrifolia (Abrom.) Polunin, J. Bot. 76: 100. 1938.

Vegetative morphology. Plants 5–15(–25) cm high; perennial herbs (with a tendency to become a sub-shrub); not caespitose. Taproot present (as the primary root from a tuft of stems). Ground level or underground stems absent (cushions), or horizontal (trailing plants); stoloniferous. Horizontal stems at ground level, branching extensively to shape plant habit as mats (sometimes dense and in large bunches). Aerial stems erect, or decumbent. Leaves present; heterophyllous; distributed along the stems; alternate (often reddish in colour); persistent, or marcescent. Petioles absent. Leaf blades simple (vegetative leaves rigid, leathery, obovate with 1–3 prickly, tooth-like lobes at the apex; upper leaves on the flowering stems, linear, entire). Leaf blade bases truncate. Blades 5–20 mm long, 1–4(–6) mm wide, linear or oblanceolate or spatulate, flat. Blade adaxial surface glabrous. Blade abaxial surface glabrous. Blades lobed (usually with 3 cusp-shaped lobes) or cut into linear divisions (less commonly). Blade margins scabrous (with a single well-developed stiff trichome on the end of each lobe or major tooth) or with non-glandular hairs, with teeth toward the apex. Hydathodes present and conspicuous (3 per leaf; each hydathode opens on the upper side of the leaf margin, and does not secrete lime).

Reproductive morphology. Flowering stems two or more per plant; with leaves (leaves on the flowering stems linear, entire). Flowering stem hairs simple; shorter than the diameter of the flowering stem; white or translucent, or brown; glandular hairs present. Inflorescences cymose; 0.5–2.5 cm long. Pedicels present; with glandular hairs. Flowers per inflorescence 3–10; medium-sized. Sepals conventional; 5; free; 1–1.5 mm long; 1.5–2.5 mm wide; green, or purple. Calyx glabrous (and somewhat ciliate). Petals conventional; free; 5; white (creamy), or yellow (when dried); with contrasting markings (yellowish orange-red or reddish brown or deep purple dots); ovate; unlobed; 6–7 mm long; 1.5–2.5 mm wide. Stamens 10; stamen filaments glabrous. Anthers yellow; ovoid, or sub-globose; 0.3–0.5 mm long. Nectaries present (small). Receptacle 0.5–0.7 mm high. Ovary superior; carpels 2; partly fused. Ovaries glabrous. Placentation axile. Ovules per ovary 50–100. Fruit with calyx persisting; dry; a capsule; ovoid (with prominent styles); brown, or red; 4–6.5 mm long; 3–4.5 mm wide; dehiscent; splitting to the base into separate segments. Seeds 50–100; 0.6–0.9 mm long; brown; surfaces smooth, ridged (seen at 40×).

Chromosome information. 2n = 26.

(2n) (2x) = 26. Böcher and Larsen (1950, Greenland); Harmsen, in Jørgensen et al. (1958, Greenland); Moore in Calder and Savile (1959, Canada); Packer (1964, northwestern Canada); Mosquin and Hayley (1966, northern Canada); Hedberg (1967, northern Canada); Johnson and Packer (1968, northwestern Alaska); Knaben (1968, central Alaska); Löve and Löve (1982a, central Canada).

Ploidy levels recorded 2x.

Indigenous knowledge. Inuit names for this taxon are kakillarnat, tiinnguat, a'asaat. Ootoova et al. (2001, p. 276) say kakillarnat means "that which causes prickly feelings" (root kaki- to prick). Tiinnguat means "tea substitute". A'asaat might be onomatopoeia, referring to the sound a person would make if they were pricked "a'aa," "ouch". The leaves have been used to make tea and were put on cuts. The plants were considered by some to be not good if eaten raw. Others enjoyed them because of their prickliness, but people were advised not to swallow them, unless they had been well chewed first (Mallory and Aiken 2004).

The plants have been used as bedding for raising husky puppies, as the prickles on the leaves are believed to cause the pads on the feet to toughen up, so that, as adult dogs, they are less likely to need booties when being used to pull komatiks on sea ice (Judith Farrow, personal communication, 1986).

Taxon as an environmental indicator. Variations in the height and the vigour of mats made up of plants of this species are dependent on local environmental conditions and indicative of the harshness of the environment. The northernmost record is Ellesmere Island, Ravine Pond, 82°30'N.

Ecology and habitat. Substrates: dry meadows, barrens; rocks, gravel (dry gravel areas, growing in scree, cliffs and rubble, and in dry oligotrophic heaths with Empetrum and Ericaceous shrubs, Elven (personal communication, 2005)); acidic (distinctly so). The flowers and the inflorescences droop before opening, but are erect during expansion. Nectar is secreted abundantly by the thick yellow base of the ovary. It is present as small drops even before the anthers open, and the secretion is continued for a very long time, even in old flowers. Protandry occurs, but anthers and stigmas are fertile throughout the greater part of the life of the flower. Self-pollination appears to take place. Fruit has been observed to ripen in West Greenland and the Canadian Arctic. The capsules are stiffly erect and gradually split open with the onset of winter, but the opening remains relatively small. When the wind reaches a certain speed the capsules vibrate, and the seeds gradually shake out. Many seeds are not shed until the winds have packed the snow into a surface as smooth and hard as an asphalt road. Since the seeds are shed only when the wind is blowing strongly, many of them are carried great distances in a single gale (Savile 1968).

North American distribution. Alaska, Yukon, Northwest Territories Islands, continental Northwest Territories, Nunavut Islands, continental Nunavut, northern Quebec, Labrador. Range in the Canadian Arctic Archipelago widespread. Common (often forming vigorous loose mats in suitable situations, and often of considerable ecological importance). Arctic. Arctic islands: Baffin, Devon, Ellesmere, Axel Heiberg, Parry islands (Bathurst, Melville, Prince Patrick), Cornwallis, Banks, Victoria, Somerset, King William, Southampton, Coats (Digges).

Northern hemisphere distribution. North American. West Alaska, North Alaska – Yukon, Central Canada, Labrador – Hudson Bay, Ellesmere Land – Peary Land, West Greenland, East Greenland.

General notes. Galloe (1910) considered this species a xerophyte based on the habitats where it grows and the internal anatomy of leaves.

This species is not known outside of North America and Greenland. Polunin (1940) stated that "the vast majority of the specimens from the Canadian Arctic Archipelago have the leaves tricuspidate, and so belong to the typical form. Some however, especially when growing in exposed habitats, have most of their leaves lacking these conspicuous lateral teeth, and a few from widely separate places have all the leaves sub-entire". Polunin (1938) recognised a forma subintegrifolia (Abrom.) Polunin, but this was not taken up by Porsild (1957).

Polunin (1940, p. 263) stated that "S. tricuspidata varies little in our area, except in luxuriance. Thus the axes may sometimes be only 5 cm high, although generally they rise to double this height and sometimes exceed 15 cm. Such luxuriant specimens growing in the most favourable situations may form extensive mats, especially in the south. The plant generally looks reddish, but in damp and shaded crevices there occur lengthened green forms, which are usually sterile". No reason for maintaining the forma recognised by Polunin (1940) has been found.

Illustrations. • Habitat. Plants with creamy yellow flowers growing in a disturbed habitat at the base of a Thule site meat cache. Nunavut, Ellesmere Island, Alexandra Fiord. L.J. Gillespie. • Tundra at Thule site: Cape Dorset. Plant indicated by marker were dominant flowering plants on very dry tundra with springy build-up of cryptogamic mat. Nunavut, Baffin Island, Cape Dorset. 3 August, 2005. Aiken. No voucher. • Habitat. Isolated plants growing on steep rocky slope. CMN Photo-Library. • Habit. Plants growing from a basal cluster of leaves. Note the flowering stems with simple leaves and inflorescences with several flowers. CMN Photo-Library. • Habit. Old flowering plants with creamy white flowers, and die-back in the reddish growth towards the right-hand side of the picture. Nunavut, Ellesmere Island, Alexandra Fiord. L.J. Gillespie. • Line drawing of leaves. A, base of plant showing alternate, clustered leaf arrangement. B, leaf apex with three sharp points that feel like prickles and explain the name 'prickly saxifrage. Warming 1909. p. 222. • Close-up of flowers. Flowers have whitish petals with red and yellowish orange spots, green sepals that are much shorter than the petals. Nunavut, Baffin Island, Pond Inlet. L.J. Gillespie 6033. CAN. • Close-up of petal markings. Note left-hand flower with 10 pre-anthesis anthers and white tips of the carpels lying side by side as they develop; centre, the most mature flower with anther filaments only, and the apices of the carpels recurving. Nunavut, Baffin Island, Iqaluit. 24 July, 2005. Photographed by Kathy Thornhill. • 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.