Ranunculus muricatus
Buttercup
(c) Don Loarie, some rights reserved (CC BY) · licence
Family: Ranunculaceae · Type: Herb · Not Native
Ranunculus muricatus (Buttercup) is a non-native California herb in the Ranunculaceae family, recognized by spiny fruits are immediately diagnostic.
Buttercup is a naturalized annual herb found in the Central Valley, Sierra Nevada Foothills, San Francisco Bay Area, and Southern California Coast in stream-banks, drainages, and low meadows at elevations below 700 meters. Flowering from April to June, this plant produces yellow flowers with reflexed sepals 4 to 7 millimeters long and petals 4 to 8 millimeters long. Growing 15 to 50 centimeters tall with decumbent or erect stems, it spreads across the ground with a sprawling habit. Its basal and lower stem leaves are widely heart-shaped to kidney-shaped, 2 to 5 centimeters long, sometimes with three lobes and coarse scalloped edges. The fruit develops with a distinctive disk-like body 5 to 5.5 millimeters wide, featuring spiny faces and a curved 2 to 2.5 millimeter beak.
Identification and appearance
Key characters: 27 sympatric species; spiny fruits are immediately diagnostic
Habitat and range
Habitat: Stream-banks, drainages, low meadows
Elevation: < 700 m
California counties: Humboldt, El Dorado, Mariposa, Butte, Calaveras, Solano, Sacramento, San Mateo, Contra Costa, Lake, Sonoma, Santa Clara, Riverside, Fresno, Napa, Amador, Stanislaus, San Joaquin, Madera, Marin, San Bernardino, San Francisco, Alameda, Orange, Placer, Sutter, Santa Cruz, Yuba, Yolo, Tuolumne, San Luis Obispo, Colusa, Tehama, Shasta, Glenn, Merced, Mendocino, Los Angeles, Ventura, Tulare, Monterey
Outside California: worldwide, native to Eurasia
Bloom period
Ranunculus muricatus blooms Apr-Jun.
How to tell it apart
vs Lasthenia: Ranunculus has separate petals around a central disk; Lasthenia has many tiny ray flowers around a disk (composite head).; vs Bowlesia: Ranunculus has glossy yellow petals in conspicuous flowers; Bowlesia has tiny white flowers in umbels with divided leaves.; vs Potentilla: Ranunculus has nectaries at petal bases and many pistils; Potentilla has no nectaries and styles attached to ovary sides.; vs Papaver: Ranunculus has 5 petals and many pistils; Papaver has 4 crinkled petals and a single large stigma disk.; vs Oxalis: Ranunculus has glossy separate petals; Oxalis has clover-like leaves and tubular flowers that close at night.
Frequently asked questions
Is Ranunculus muricatus native to California?
No. Ranunculus muricatus is not native to California (recorded as not native).
When does Ranunculus muricatus bloom?
Ranunculus muricatus blooms Apr-Jun.
Where in California does Ranunculus muricatus grow?
Ranunculus muricatus occurs in Humboldt, El Dorado, Mariposa, Butte, Calaveras, Solano, Sacramento, San Mateo and other counties, at elevations of < 700 m.
What plant family does Ranunculus muricatus belong to?
Ranunculus muricatus is in the Ranunculaceae family, genus Ranunculus.
What habitat does Ranunculus muricatus grow in?
Ranunculus muricatus grows in Stream-banks, drainages, low meadows.
Related species
Other California species in the same genus, family, or bioregion.
- Ranunculus occidentalis — Western buttercup
- Ranunculus occidentalis var. dissectus — Western buttercup
- Ranunculus occidentalis var. howellii — Western buttercup
- Ranunculus occidentalis var. occidentalis — Western buttercup
- Ranunculus occidentalis var. ultramontanus — Western buttercup
- Ranunculus orthorhynchus — Bloomer's buttercup
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.