Ophioglossum californicum
California adder's-tongue
(c) Madeleine Claire, some rights reserved (CC BY) · licence
Family: Ophioglossaceae · Type: Herb · Native
Conservation status: CNPS 4.2
Ophioglossum californicum (California adder's-tongue) is a native California herb in the Ophioglossaceae family, recognized by low elevation valley/coastal habitat.
California adder's-tongue is a native perennial ranked 4.2 by CNPS, found in northern and central Sierra Nevada Foothills, Central Valley, Central Coast, Southern Coast, and southwestern Peninsular Ranges in grassy pastures, chaparral, and vernal pool margins at elevations of 60 to 450 meters. Its distinctive green leaf blade is generally folded and thick, with a single fertile stalk rising 1 to 2.5 times the length of the sterile portion. Growing with a small caudex less than 20 millimeters long and 4 millimeters wide, this delicate fern relative emerges discretely in scattered patches. Its leaf blade supports 8 to 15 pairs of sporangia arranged in compact rows 8 to 15 millimeters long. The sterile tip of its fertile stalk measures a tiny 0.3 to 1 millimeter, making this an easily overlooked but fascinating botanical specimen.
Identification and appearance
Key characters: Geographically isolated; distinguished by low elevation valley/coastal habitat
Habitat and range
Habitat: Uncommon but sometimes locally abundant, often overlooked. Grassy pastures, chaparral, vernal pool margins
Elevation: 60-450 m
California counties: San Diego, Stanislaus, Butte, Amador, Monterey, Los Angeles, Merced, Mariposa, Santa Barbara
Outside California: Mexico
Conservation status
CNPS 4.2
How to tell it apart
vs Botrypus: Ophioglossum has a simple, undivided oval blade; Botrypus has finely divided, lacy leaves.; vs Sceptridium: Ophioglossum's leaf is completely simple and tongue-shaped, not divided like Sceptridium's compound blade.; vs Botrychium: Check for a simple, entire leaf blade - Botrychium always has divided, compound leaves.
Frequently asked questions
Is Ophioglossum californicum native to California?
Yes. Ophioglossum californicum is native to California (recorded as native).
Where in California does Ophioglossum californicum grow?
Ophioglossum californicum occurs in San Diego, Stanislaus, Butte, Amador, Monterey, Los Angeles, Merced, Mariposa and other counties, at elevations of 60-450 m.
What plant family does Ophioglossum californicum belong to?
Ophioglossum californicum is in the Ophioglossaceae family, genus Ophioglossum.
Is Ophioglossum californicum rare or endangered?
Ophioglossum californicum carries California Rare Plant Rank 4.2, state rank S4.
What habitat does Ophioglossum californicum grow in?
Ophioglossum californicum grows in Uncommon but sometimes locally abundant, often overlooked. Grassy pastures, chaparral, vernal pool margins.
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.