Callitriche heterophylla var. heterophylla
Varied leaved water starwort
Photo: parent species Callitriche heterophylla · no rights reserved · CC0
Family: Plantaginaceae · Type: Herb · Native
Callitriche heterophylla var. heterophylla (Varied leaved water starwort) is a native California herb in the Plantaginaceae family, recognized by smallest fruit size is key diagnostic feature.
Varied leaved water starwort is a California native perennial found in northwestern, Great Valley, central western, and southwestern California in submerged habitats of lakes, pools, and streams at elevations below 2,000 meters. Flowering from April to July, this aquatic plant produces small, inconspicuous flowers in delicate rosettes that float on or near water surfaces. Growing with slender, branching stems that adapt to underwater and shoreline environments, it forms intricate clusters of fine, thread-like vegetation. Its leaves vary in shape, with submerged leaves typically linear and narrower, while floating leaves are broader and more rounded, creating a distinctive heteromorphic growth pattern. The fruit is tiny, measuring less than one millimeter long, contributing to the plant's subtle and delicate nature.
Identification and appearance
Key characters: Co-occurs with 7 species; smallest fruit size is key diagnostic feature
Habitat and range
Habitat: Submerged, with floating rosettes or becoming stranded at edge of lake, pools, or streams
Elevation: < 2000 m
Outside California: Canada, eastern United States, northern Mexico, naturalized in New Zealand
Bloom period
Callitriche heterophylla var. heterophylla blooms Apr-Jul.
How to tell it apart
vs Nasturtium: Nasturtium has bright yellow or white 4-petaled flowers; Callitriche has no petals, just tiny styles.; vs Lemna: Lemna is free-floating duckweed with no roots in substrate; Callitriche is rooted with opposite-leaved stems.; vs Ludwigia: Ludwigia has showy yellow flowers and consistent leaf shape; Callitriche lacks petals and has dimorphic leaves.; vs Soleirolia: Soleirolia is terrestrial with round leaves; Callitriche is aquatic with narrow or spoon-shaped leaves.; vs Stellaria: Stellaria has notched white petals on terrestrial plants; Callitriche lacks petals and forms aquatic rosettes.
Frequently asked questions
Is Callitriche heterophylla var. heterophylla native to California?
Yes. Callitriche heterophylla var. heterophylla is native to California (recorded as native).
When does Callitriche heterophylla var. heterophylla bloom?
Callitriche heterophylla var. heterophylla blooms Apr-Jul.
What plant family does Callitriche heterophylla var. heterophylla belong to?
Callitriche heterophylla var. heterophylla is in the Plantaginaceae family, genus Callitriche.
What habitat does Callitriche heterophylla var. heterophylla grow in?
Callitriche heterophylla var. heterophylla grows in Submerged, with floating rosettes or becoming stranded at edge of lake, pools, or streams.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · 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.