Eucnide rupestris
Annual rock-nettle
(c) Madeleine Claire, some rights reserved (CC BY) · licence
Family: Loasaceae · Type: Herb · Native
Conservation status: CNPS 2B.2
Eucnide rupestris (Annual rock-nettle) is a native California herb in the Loasaceae family, recognized by clear size and leaf shape differences from E. urens.
Annual rock-nettle is a rare (CNPS 2B.2) California native annual found in southern Desert Southwest region, specifically Painted Gorge in Imperial County, inhabiting rocky crevices and cliff environments at elevations of 180 to 450 meters. Flowering from December to April, this plant produces shiny green leaves with white to pale flowers emerging in delicate clusters. Growing less than 30 centimeters tall with slender stems, it develops a compact, low-spreading form characteristic of cliff-dwelling plants. Its rounded leaves are 1 to 8 centimeters long, widely tapered with toothed edges, presenting a glossy green appearance above. The fruit develops as a small cylindric structure 7 to 15 millimeters long, with reflexed pedicels supporting its delicate structure.
Identification and appearance
Key characters: 1 sympatric species; clear size and leaf shape differences from E. urens
Habitat and range
Habitat: Crevices, cliffs
Elevation: 180-450 m
California counties: Imperial, San Diego
Outside California: Arizona, northern Mexico (including islands)
Bloom period
Eucnide rupestris blooms Dec-Apr.
Conservation status
CNPS 2B.2
How to tell it apart
vs Mentzelia: Eucnide has petals fused at base and 5 stigma lobes; Mentzelia has free petals and 3 stigma lobes.; vs Petalonyx: Eucnide is an annual herb; Petalonyx is a woody shrub.; vs Sherardia: Eucnide has many stamens and stinging hairs; Sherardia has 4 stamens and no stinging hairs.; vs Sambucus: Eucnide is an annual with stinging hairs; Sambucus is a woody shrub without stinging hairs.; vs Viburnum: Eucnide is an annual desert herb; Viburnum is a woody shrub.
Frequently asked questions
Is Eucnide rupestris native to California?
Yes. Eucnide rupestris is native to California (recorded as native).
When does Eucnide rupestris bloom?
Eucnide rupestris blooms Dec-Apr.
Where in California does Eucnide rupestris grow?
Eucnide rupestris occurs in Imperial, San Diego, at elevations of 180-450 m.
What plant family does Eucnide rupestris belong to?
Eucnide rupestris is in the Loasaceae family, genus Eucnide.
Is Eucnide rupestris rare or endangered?
Eucnide rupestris carries California Rare Plant Rank 2B.2, state rank S1.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CNPS Rare Plant Inventory · Index of California Plant Names · CalPhotos · CDFW CNDDB
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.