Najas gracillima

Thread-leaved water-nymph, Thread-Leaved Water-Nymph

Family: Hydrocharitaceae · Type: annual · Not Native

Thread-leaved water-nymph is a naturalized annual aquatic plant found in northern Sacramento Valley rivers and lakes at elevations around 100 meters. Flowering from June to August, this delicate plant produces tiny, inconspicuous flowers with subtle reproductive structures. Growing as a monoecious plant with slender stems, it spreads through aquatic environments with fine, thread-like vegetative characteristics. Its narrow leaves feature 13 to 17 teeth along each margin, with acute tips and a distinctive truncate sheath. The small seeds are fusiform-shaped, with a pitted, dull coat measuring 0.4 to 0.7 millimeters long.

Habitat: Rivers, lakes

Bloom period: Jun-Aug

Elevation: +- 100 m.

Bioregions: n ScV, expected elsewhere

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