Scientific name

Didiplis Raf.

Common names

waterpurslane, blood stargrass, waterhedge



Could be confused with

Callitriche, Ludwigia, Lythrum, Rotala

Native distribution

eastern North America

Species commonly cultivated

Didiplis diandra (Nutt. ex DC.) Wood (North America)

Adventive distribution


Weed status

not weedy

Brief description

Annual or short-lived perennial. Stems ascending or creeping, slender, with adventive roots produced from lower nodes. Leaves opposite, decussate, sessile, linear (submersed) to elliptic (emersed), entire, mid-vein prominent. Flowers small, axillary, solitary, sessile, actinomorphic; sepals fused, lobes 4; petals absent. Dispersal by seed and stem fragments.

Natural habitat

variety of habitats from lakes and ponds to rivers and marshes

Additional comments

Didiplis diandra is the only species in the genus Didiplis and is widely cultivated in the aquarium trade. This species is sometimes difficult to cultivate submersed due to high light requirements. Didiplis is considered threatened in some states of the U.S.