Leaves connate at base, obovate-spatulate to ± round, 4–9 × 1–4 mm, 1+-veined. Stem and leaf scales present. Inflorescences: bracts persistent. Pedicels 0–0.2 mm in fruit. Flowers solitary; styles erect; pollen yellow. Schizocarps 1.2–1.8 × 1–1.7 mm, ± as long as wide; mericarps pale grayish brown, not swollen, winged throughout, wings straight, 0.1–0.5 mm wide. 2n = 10.

Phenology: Flowering May–Oct.
Habitat: Standing water, stream margins, backwaters, ponds, pools, ditches.
Elevation: 0–1500 m.

Distribution

• Generated Map
• Legacy Map

Introduced; St. Pierre and Miquelon, B.C., Nfld. and Labr. (Nfld.), Que., Ala., Calif., Conn., Maine, Md., Mass., Mo., Mont., N.J., N.Y., Oreg., Pa., Va., Wash., Wis., Europe, introduced also in Australia.

Discussion

Selected References

Philbrick, C. T., R. A. Aakjar Jr., and R. L. Stuckey. 1998. Invasion and spread of Callitriche stagnalis (Callitrichaceae) in North America. Rhodora 100: 25–38.

Lower Taxa

None.