Herbs, usually annual or perennial, occasionally biennial in Claytonia rubra. Roots branched, capillary or fibrous. Stems: subterranean stems tubers, rhizomes, or woody caudices, sometimes with multiple forms on single individuals (e.g., C. umbellata and C. tuberosa); aerial stems erect or decumbent; nodes glabrous. Leaves basal and cauline, not articulate at base, somewhat to markedly clasping, attachment points linear; basal leaves few to several in rosettes, blade linear, lanceolate, oblanceolate, spatulate, trullate, rhomboid, ovate, or deltate, apex obtuse to apiculate; cauline leaves 2 and opposite, rarely 3 and whorled, distinct or partially or completely connate, or perfoliate, blade linear to ovate. Inflorescences terminal, racemose or umbellate, secund, bracteate; bracts leaflike or membranous and scalelike. Flowers showy; sepals persistent, leaflike, unequal; petals 5; stamens 5, adnate to petal bases; ovary globose, ovules 3 or 6; style 1; stigmas 3. Capsules 3-valved, longitudinally dehiscent from apex, valves not deciduous, margins hygroscopic, involute. Seeds (1–)3–6, black, rounded, shiny and smooth to tuberculate, with white elaiosome; seeds dispersed ballistically and by ants. x = 5, 6, 7, 8.

Distribution

North America, (including Mexico), Central America (Guatemala), Asia, adventive in Europe and New Zealand. A related species, Claytonia joanneana Roemer & Schultes, occurs in the Altai Mountains of Siberia and Mongolia.

Discussion

Species 26 (25 in the flora).

Selected References

Chambers, K. L. 1993. Claytonia. In: J. C. Hickman, ed. 1993. The Jepson Manual. Higher Plants of California. Berkeley, Los Angeles, and London. Pp. 898–900.

Davis, R. G. 1966. The North American perennial species of Claytonia. Brittonia 18: 285–303.

Doyle, J. J. 1984. Karyotypic variation of eastern North American Claytonia chemical races. Amer. J. Bot. 71: 970–978.

Halleck, D. K. and D. Wiens. 1966. Taxonomic status of Claytonia rosea and C. lanceolata (Portulacaceae). Ann. Missouri Bot. Gard. 53: 205–212.

Lewis, W. H. 1967. Cytocatalytic evolution in plants. Bot. Rev. (Lancaster) 33: 105–115.

Lewis, W. H., R. L. Oliver, and Y. Suda. 1967. Cytogeography of Claytonia virginica and its allies. Ann. Missouri Bot. Gard. 54: 153–171.

Lewis, W. H. and Y. Suda. 1968. Karyotypes in relation to classification and phylogeny in Claytonia. Ann. Missouri Bot. Gard. 55: 64–67.

McNeill, J. 1972. New taxa of Claytonia section Claytonia (Portulacaceae). Canad. J. Bot. 50: 1895–1898.

Miller, J. M. and K. L. Chambers. 1993. Nomenclatural changes and new taxa in Claytonia (Portulacaceae) in western North America. Novon 3: 268–273.

Packer, J. G., ed. 1995+. Flora of the Russian Arctic.... 3+ vols. Edmonton. Vol. 3, pp. 195–204.

Lower Taxa

Claytonia acutifolia, Claytonia arctica, Claytonia arenicola, Claytonia caroliniana, Claytonia cordifolia, Claytonia exigua, Claytonia gypsophiloides, Claytonia lanceolata, Claytonia megarhiza, Claytonia multiscapa, Claytonia nevadensis, Claytonia ogilviensis, Claytonia palustris, Claytonia parviflora, Claytonia perfoliata, Claytonia rosea, Claytonia rubra, Claytonia sarmentosa, Claytonia saxosa, Claytonia scammaniana, Claytonia sibirica, Claytonia tuberosa, Claytonia umbellata, Claytonia virginica, Claytonia washingtoniana

Key

1	Plants annual, sometimes biennial, with minute, tuberous bodies	> 2
1	Plants perennial, with stolons, rhizomes, tubers, or woody caudices	> 10
2	Inflorescences with 2-several bracts (rarely only 2); proximalmost bract leaflike, distal bracts leaflike or reduced to membranous scales	> 3
2	Inflorescence ebracteate or 1-bracteate; bract leaflike	> 5
3	Flowers 4-8 mm diam.; petals not candy-striped; basal leaf blades rhombic or ovate	Claytonia washingtoniana
3	Flowers 8-20 mm diam.; petals white, candy-striped, or pink; basal leaf blades linear to deltate	> 4
4	Cauline leaf blades linear; distal bracts reduced to membranous scales; seeds (1-)6	Claytonia arenicola
4	Cauline leaf blades broad; distal bracts leaflike; seeds (1-)3	Claytonia sibirica
5	Flowers 10-15 mm diam.; inflorescences ebracteate	Claytonia saxosa
5	Flowers 2-12 mm diam.; inflorescences 1-bracteate	> 6
6	Basal leaf blades usually trullate or rhombic to deltate, sometimes spatulate, less than 3 times longer than wide	> 7
6	Basal leaf blades usually linear, sometimes spatulate, blade much longer than wide	> 8
7	Basal rosettes flattened to suberect; leaf blades trullate, spatulate, or narrowly rhombic to ovate, apex obtuse, red pigmentation often strong even in juvenile plants	Claytonia rubra
7	Basal rosettes suberect to erect, seldom flattened; leaf blades broadly rhombic to deltate or reniform, apex obtuse to apiculate, red pigmentation often weak	Claytonia perfoliata
8	Seeds often smooth or with low tubercles, not pebbly; leaf blades not glau- cous, green or pink	Claytonia parviflora
8	Seeds often tuberculate and pebbly; leaf blades glaucous, gray, beige, or pink	> 9
9	Flowers 3-5 mm diam	Claytonia exigua
9	Flowers 6-12 mm diam	Claytonia gypsophiloides
10	Plants with tubers sometimes connected by rhizomes	> 11
10	Plants with rhizomes or woody caudices	> 19
11	Bracts 2 or more, distal bracts leaflike or reduced to membranous scales; cauline leaves often strongly tapered in basal 1/2	> 12
11	Bracts 1 or absent, (rarely 2 in C. caroliniana); cauline leaves seldom tapered in no more than basal 1/4	> 15
12	Bracts all leaflike; tubers napiform	Claytonia ogilviensis
12	Proximalmost bract leaflike, distal bracts reduced to membranous scales; tubers globose	> 13
13	Petals white with yellow blotch at base	Claytonia tuberosa
13	Petals white, pink, rose, magenta, cream, yellow, or yellow-orange, lacking yellow blotch at base	> 14
14	Petals pink, rose, or magenta	Claytonia rosea
14	Petals white, cream, yellow, or yellow-orange	Claytonia multiscapa
15	Bracts absent; petals pink to magenta	Claytonia umbellata
15	Bracts present; petals white, white with yellow blotch at base, yellow, orange, or candy-striped (sometimes pink, rose, or magenta in C. caroliniana, C. lanceolata, and C. virginica)	> 16
16	Cauline leaf blades linear, 0.2-1.2 cm wide, tapered to slender base	> 17
16	Cauline leaf blades lanceolate or spatulate to ovate, 0.4-2.5 cm wide, abruptly petiolate or sessile	> 18
17	Petals white, pinkish, or rose, candy-striped, rarely yellow or orange, or white with pink-lavender candy-stripes; e North America to Texas	Claytonia virginica
17	Petals white with yellow blotch at base; Alaska, Yukon	Claytonia tuberosa
18	Basal leaves 6-21; cauline leaves petiolate; e North America	Claytonia caroliniana
18	Basal leaves 1-6 or absent; cauline leaves sessile; w North American cordillera	Claytonia lanceolata
19	Plants with woody caudices	> 20
19	Plants rhizomatous	> 22
20	Basal leaves and bracts with apex acute; petals white or pink to bright rose with yellow blotches at base, or white	Claytonia acutifolia
20	Basal leaves and bracts (where present) with apex obtuse; petals usually pink to magenta, sometimes yellow or white	> 21
21	Stems 1-10 cm; bracts absent; Alaska	Claytonia arctica
21	Stems 10-50 cm; bracts present; not in Alaska	Claytonia megarhiza
22	Bracts present; seeds (1-)3	> 23
22	Bracts absent; seeds (1-)6	> 24
23	Cauline leaves equal, sessile, blade lanceolate to ovate; basal leaf blades 1-5 cm wide	Claytonia sibirica
23	Cauline leaves unequal, petiolate, blade linear to spatulate; basal leaf blades 0.1-1 cm wide	Claytonia palustris
24	Rhizomes 0.5-3 mm diam.; Alaska, Yukon, n British Columbia	> 25
24	Rhizomes 4-8 mm diam.; w United States	> 26
25	Basal leaf baldes linear to narrowly spatualte, 1-10 × 0.1-1 cm	Claytonia scammaniana
25	Basal leaf blades elliptic to spatulate, 1-8 × 1-2 cm	Claytonia sarmentosa
26	Basal leaf blades deltate to ovate or cordate; cauline leaf blades 1-5 cm; petals white	Claytonia cordifolia
26	Basal leaf blades spatulate to rhombic or ovate; cauline leaf blades 0.5-2 cm; petals pink to magenta	Claytonia nevadensis