Saxifraga eschscholtzii Sternb.
Saxifragaceae, saxifrage family.
Revis. Saxifrag., Suppl. 1: 9. 1822
Type: Russian Far East: Chukchi Peninsula, St. Lawrence Bay, leg. Chamisso and Eschscholtz, syntypes in LE.
Vegetative morphology. Plants perennial herbs; 1–5 cm high; caespitose, or not caespitose; cushion-or lichen-like amats. Caudex absent. Ground-level or under-ground stems not developed horizontally or vertically (cushions), or horizontal (trailing plants); rhizomatous; elongate. Aerial stems erect, or decumbent (numerous, densely compacted); glabrous. Leaves not heterophyllous; in a basal tuft, or distributed along the stems (trailing stems); alternate (overlapping densely); simple; marcescent (turning pale brown or grey). Petioles absent. Leaf blade bases truncate, or hastate (trailing stems). Blades 2–4 mm long; 1–2.5 mm wide. Blades obovate, or spatulate; flat; with inconspicuous veins. Blades adaxial surface glabrous. Blades abaxial surface glabrous. Blade margins not lobed. Blade margins serrate; with non-glandular hairs (stiff hyaline trichomes, some approaching 1 mm long). Conspicuous hydathodes absent (in contrast to S. oppositifolia. Caution: dead leaves may turn white and superficially resemble lime deposits). Leaf apices obtuse, or rounded.
Reproductive morphology. Plants monoecious, or bisexual. Flowering stems present. Flowering stems without leaves; glabrous. Flowers solitary; small, less than 5 mm in diameter or length (female flowers with large purplish carpels and stamens with small anthers; male flowers with abortive carpels and large yellow anthers). Calyx sepals 5; free; 1–1.4 mm long; 0.5–1 mm wide. Calyx purple; scarious; hairy. Calyx hairs non-glandular; white or translucent. Calyx margins ciliate (relatively long trichomes, similar to the leaf margins). Petals free; same length as the calyx; 5; yellow, or pink (drying pale brown); elliptic (narrowly), or spatulate; unlobed; 1.5–2.5 mm long; 0.4–0.6 mm wide. Stamens 10; filaments glabrous. Anthers yellow; subglobose; 0.3–0.5 mm long. Nectaries present. Receptacle 0.1–0.2 mm high. Gynoecia superior. Carpels partly fused (for more than half their length); 2. Ovaries glabrous. Styles present; 2; free. Stigmas per style 1; plate shaped, or receptive surface at the end of an otherwise unmodified style. Placentation axile. Ovules 10–50. Fruit with calyx persisting (becoming reflexed); dry; a capsule; ovoid (with divergent styles); dehiscent; splitting to the base into separate segments. Fruit (2.5–)2.8–3.2 mm long; 1.5–1.8 mm wide; purple. Seeds 10–25; 0.6–1 mm long; brown; with surfaces smooth (with fine markings seen at 40x).
Chromosome information. 2n = 12. - Zhukova (1967 north eastern Asia); Johnson and Packer (1968 northwestern Alaska ); Zhukova and Petrovsky (1987a north eastern Asia). Ploidy levels recorded 2x.
Distribution. Northern hemisphere distribution: amphi-Beringian. Alpine (species ranging eastwards along the Brooks Range. In Canada, known from the North Yukon, from sea level to slopes of the Buckland Hills and British Mountains, and a single record from Prince Patrick Island (Porsild and Cody 1980). Range in the Canadian Arctic Archipelago limited. Rare. Arctic Islands: Parry Islands (Prince Patrick Island).
Ecology and habitat. Substrates: calcareous; rocks (particularly gravel, in crevices, and on rocky ledges).
Taxon as an environmental indicator. The northernmost record, and first collection for the Arctic Archipelago, is N.W.T. Prince Patrick Island, Greene Bay, 76°54'N, 119°30'W, 7 July, 1968, M. Kuc s.n. (Canada).
Notes. This species is superficially similar to S.
oppositifolia, but differs in its grey green foliage and alternate leaves.
It was first collected on the Arctic Archipelago in 1968. It is possibly
under-collected as it resembles lichens when not flowering.
It is an
Amphi-Beringian mainly arctic species, closely related to S.
hemisphaerica Hook.f. and Thoms., distributed in the Himalayas high
mountains. (Zhmylev). There is a question concerning the priority of the name as
Saxifraga fimbriata D.Don (1822), Trans. Linn. Soc. (London) 13: 404, the
same taxon, was described in the same year.
Illustrations. • Close-up of vegetative plants. Dense polster of grey-green plants. Alaska: Alaska Range, Kantishna, Elodrado Creek. July 1998. Photo: R.Elven. • Close-up of fruiting plants. Polster with plant that has grey-green leaves and dehisced brown capsules. Alaska: Alaska Range, Mt Healy. July 1998. Photo: R.Elven. Voucher in HbO. • Plant habit. Plants easily mistaken for lichens. The leaves are alternate, the flowers borne singly. This picture shows fruit capsules with the tops of the carpels at right angles to the fruit. • Herbarium specimens CAN 385465.. • 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).
