Myosurus cupulatus
Arizona mousetail
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Family: Ranunculaceae · Type: Herb · Native
Myosurus cupulatus (Arizona mousetail) is a native California herb in the Ranunculaceae family.
Arizona mousetail is a California native annual found in the eastern desert mountains on dry hillsides or canyon bottoms at elevations of 350 to 1,700 meters. Flowering from March to May, this plant produces small white to greenish flowers arranged on slender scapes rising above its low-growing foliage. Growing with delicate stems 3 to 16 centimeters tall, it forms compact clusters close to the ground. Its tiny leaves are arranged in a basal rosette, creating a low, understated profile in its arid habitat. The fruit develops as a distinctive round aggregate with a slight ridge, featuring a short divergent beak that extends slightly from the leaf cluster.
Identification and appearance
Key characters: Geographically isolated species in desert mountains with no sympatric congeners
Habitat and range
Habitat: dry hillsides or canyon bottoms in scrub
Elevation: 350-1700 m
California counties: San Bernardino, Inyo
Outside California: to Texas, northern Mexico
Bloom period
Myosurus cupulatus blooms Mar-May.
How to tell it apart
vs Triglochin: Myosurus has distinctive elongated cone-shaped fruiting heads; Triglochin has slender spikes of scale-like flowers.; vs Typha: Myosurus is a tiny annual inches tall; Typha is a robust perennial several feet tall with brown flower heads.; vs Sparganium: Myosurus has cone-shaped receptacles on single stems; Sparganium has round, burr-like heads in branched clusters.; vs Juncus: Myosurus is an annual with elongated fruiting cones; Juncus is perennial with round capsules in branched clusters.
Frequently asked questions
Is Myosurus cupulatus native to California?
Yes. Myosurus cupulatus is native to California (recorded as native).
When does Myosurus cupulatus bloom?
Myosurus cupulatus blooms Mar-May.
Where in California does Myosurus cupulatus grow?
Myosurus cupulatus occurs in San Bernardino, Inyo, at elevations of 350-1700 m.
What plant family does Myosurus cupulatus belong to?
Myosurus cupulatus is in the Ranunculaceae family, genus Myosurus.
What habitat does Myosurus cupulatus grow in?
Myosurus cupulatus grows in dry hillsides or canyon bottoms in 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.