Myosurus sessilis

Tiny mouse tail

Family: Ranunculaceae · Type: annual · Native

Tiny mouse tail is a California native annual found in the Great Valley bioregion in vernal pools and alkali flats at elevations of 3 to 1,600 meters. Flowering from March to May, this diminutive plant produces tiny white to pale yellow flowers with delicate, nearly invisible structures. Growing extremely small, typically 0.8 to 2.5 centimeters tall with minimal stem development, it forms compact, ground-hugging clusters. Its leaves are subtle and nestled close to the ground, creating a miniature landscape of intricate botanical detail. The fruit develops in narrow, rhomboid shapes with a tiny diverging beak, forming an aggregate structure up to 25 millimeters long.

Habitat: Vernal pools, alkali flats

Bloom period: Mar-May

Elevation: 3-1600 m

Bioregions: GV

California counties: San Benito, Colusa, Yolo, Contra Costa, Tulare, Fresno, Butte, Tehama, Glenn, Merced, Alameda, Siskiyou, Stanislaus, Solano, San Luis Obispo, San Joaquin

Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Jepson eFlora, Cal-IPC, and more.