Herbs, annual, not rhizomatous or stoloniferous. Stems prostrate to erect, branched; nodes glabrous. Leaves alternate, not articulate at base, somewhat to markedly clasping, attachment points linear; blade linear to oblanceolate, or ovate to spatulate, flattened, glabrous or with elongate unicellular hairs. Inflorescences racemose, somewhat to markedly secund (at least distally), elongate, bracteate; bracts leaflike. Flowers pedicellate; sepals persistent in fruit, imbricate, green, distinctly angled or keeled, ovate, herbaceous, glabrous or with elongate, unicellular hairs; petals usually 5, red; stamens 3–15, usually opposite petals, not adnate to petals; ovules 6–many; style present; stigmas 3. Capsules 3-valved, longitudinally dehiscent from apex, valves not deciduous, reflexed after dehiscence, margins markedly involute; endocarp and exocarp not separating. Seeds 10–20, black, ± ellipsoid, reticulate or tuberculate viewed at 30×, glabrous, estrophiolate. x = 12.

Distribution

Temperate w Americas, with greater diversity in w South America.

Discussion

Species 14 (2 in the flora).

Selected References

Ford, D. I. 1992. Systematics and Evolution of Montiopsis Subgenus Montiopsis (Portulacaceae). Ph.D. thesis. Washington University.

Hershkovitz, M. A. 1993b. Leaf morphology of Calandrinia and Montiopsis (Portulacaceae). Ann. Missouri Bot. Gard. 80: 366–396.

Hershkovitz, M. A. 1993. Revised circumscriptions and subgeneric taxonomies of Calandrinia and Montiopsis with notes on phylogeny of the portulacaceous alliance. Ann. Missouri Bot. Gard. 80: 333–365.

Kelley, W. A. 1973. Pollen Morphology and Relationships in Calandrinia H. B. K. (Portulacaceae). M.S. thesis. California State University, Northridge.

Lower Taxa

Calandrinia breweri, Calandrinia ciliata

Key

1	Capsules usually exceeding calyx by 3+ mm; seeds at 30× partially or totally finely tuberculate	Calandrinia breweri
1	Capsules usually not exceeding calyx by 3+ mm; seeds at 30× finely reticulate	Calandrinia ciliata