Chorizanthe biloba var. immemora
Hernandez spineflower, Hernandez Spineflower
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Family: Polygonaceae · Type: Herb · Native
Conservation status: CNPS 1B.2
Chorizanthe biloba var. immemora (Hernandez spineflower) is a native California herb in the Polygonaceae family, recognized by notched vs deeply 2-lobed petals distinguish from var. biloba.
Hernandez spineflower is a rare (CNPS 1B.2) California native perennial found in eastern San Luis Obispo and San Benito and eastern Monterey counties on serpentine, gravel, and vertic clay habitats at elevations of 600 to 800 meters. Flowering from May to September, this plant produces white to pale flowers with distinctive outer perianth lobes that are notched or slightly heart-shaped at the tip. Growing with delicate branching stems typically 10 to 30 centimeters tall, it forms compact clusters in harsh serpentine environments. Its leaves are small and narrow, adapting to the challenging clay and rocky substrates where it thrives. The plant's unique chromosome count of 17 to 23 and specialized flower structure make it a remarkable endemic of California's serpentine landscapes.
Identification and appearance
Key characters: 12 sympatric species; notched vs deeply 2-lobed petals distinguish from var. biloba
Habitat and range
Habitat: Serpentine, gravel, vertic clay
Elevation: 600-800 m
California counties: San Benito, Fresno, Monterey
Bloom period
Chorizanthe biloba var. immemora blooms May-Sep.
Conservation status
CNPS 1B.2
How to tell it apart
vs Eriogonum: Chorizanthe has 1 flower per involucre; Eriogonum has multiple flowers per involucre.; vs Eremothera: Chorizanthe has 6-parted flowers in spiny cups; Eremothera has 4-petaled evening-primrose flowers.; vs Calyptridium: Chorizanthe has flowers in awned involucres; Calyptridium has naked flowers with papery sepals.; vs Lastarriaea: Chorizanthe has thin papery flowers; Lastarriaea has distinctly thick, leathery-textured flowers.; vs Navarretia: Chorizanthe is in Polygonaceae with 6-parted flowers; Navarretia is in Polemoniaceae with 5-lobed tubular flowers.
Frequently asked questions
Is Chorizanthe biloba var. immemora native to California?
Yes. Chorizanthe biloba var. immemora is native to California (recorded as native).
When does Chorizanthe biloba var. immemora bloom?
Chorizanthe biloba var. immemora blooms May-Sep.
Where in California does Chorizanthe biloba var. immemora grow?
Chorizanthe biloba var. immemora occurs in San Benito, Fresno, Monterey, at elevations of 600-800 m.
What plant family does Chorizanthe biloba var. immemora belong to?
Chorizanthe biloba var. immemora is in the Polygonaceae family, genus Chorizanthe.
Is Chorizanthe biloba var. immemora rare or endangered?
Chorizanthe biloba var. immemora carries California Rare Plant Rank 1B.2, state rank S1S2.
Related species
Other California species in the same genus, family, or bioregion.
- Chorizanthe blakleyi — Blakley's spineflower
- Chorizanthe brevicornu — Brittle spine flower
- Chorizanthe brevicornu var. brevicornu — Brittle spineflower
- Chorizanthe brevicornu var. spathulata — Great basin brittle spineflower
- Chorizanthe breweri — Brewer's spineflower
- Chorizanthe clevelandii — Cleveland's spineflower
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.