Calyptridium roseum
Rosy calyptridium
(c) Jim Morefield, some rights reserved (CC BY) · licence
Family: Montiaceae · Type: Herb · Native
Calyptridium roseum (Rosy calyptridium) is a native California herb in the Montiaceae family, recognized by . Uniquely distinguished by 2 petals and 1 stamen.
Rosy calyptridium is a California native annual found on the eastern slope of the Sierra Nevada Mountains, northern Sierra Nevada, and White and Inyo Mountains in gravelly soils, conifer forest, and sagebrush scrub at elevations of 1,500 to 3,800 meters. Flowering from May to August, this delicate plant produces white petals in tiny, sparse clusters with slender pedicels. Growing with spreading to ascending stems 1.5 to 10 centimeters tall, it forms a low, compact plant with a slender or fibrous taproot. Its leaves are both basal and along the stem, measuring 0.5 to 4 centimeters long and typically persisting through fruiting. The small fruit contains 10 to 25 shiny seeds, each less than half a millimeter long with marginal papillae.
Identification and appearance
Key characters: 5 sympatric species. Uniquely distinguished by 2 petals and 1 stamen.
Habitat and range
Habitat: Gravelly soils, conifer forest, sagebrush scrub
Elevation: 1500-3800 m
California counties: Tulare, Mono, Inyo, Lake
Outside California: to Oregon, Wyoming, Utah
Bloom period
Calyptridium roseum blooms May-Aug.
How to tell it apart
vs Eriogonum: Calyptridium has separate petals; Eriogonum flowers are in papery involucres with 6 petal-like tepals.; vs Cistanthe: Calyptridium has 2-4 petals and 1-3 stamens; Cistanthe consistently has 5 petals and 5-10 stamens.; vs Chorizanthe: Calyptridium has distinct petals; Chorizanthe has tubular flowers with papery bracts and no true petals.; vs Camissoniopsis: Calyptridium has 2-4 petals with few stamens; Camissoniopsis has 4 petals with 8 stamens.; vs Claytonia: Calyptridium has only 2-4 petals and dense ground-hugging clusters; Claytonia has 5 petals on upright stems.
Frequently asked questions
Is Calyptridium roseum native to California?
Yes. Calyptridium roseum is native to California (recorded as native).
When does Calyptridium roseum bloom?
Calyptridium roseum blooms May-Aug.
Where in California does Calyptridium roseum grow?
Calyptridium roseum occurs in Tulare, Mono, Inyo, Lake, at elevations of 1500-3800 m.
What plant family does Calyptridium roseum belong to?
Calyptridium roseum is in the Montiaceae family, genus Calyptridium.
What habitat does Calyptridium roseum grow in?
Calyptridium roseum grows in Gravelly soils, conifer forest, sagebrush scrub.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.