Common name: East Indian hygrophila, Miramar weed, Indian swampweed
Hygrophila polysperma (Roxb.) T.Anderson APNI*
Description: Aquatic perennial herb in freshwater, occasionally prostrate along edges of watercourses.
Leaves oblong-elliptic, opposite with entire margins, 2–6 cm long and 0.5–2 cm wide, sparsely covered with hairs.
Flowers solitary, sessile and axillary; corolla bluish-white to white, tubular with two lips, upper lip 2-lobed, lower lip 3-lobed, 1 cm long; calyx hairy, with 5 lobes; stamens 2.
Capsule 6–7 mm long, lacking hooks; 20–30 tiny flattened-circular seeds .
Flowering: Flowering chiefly in autumn and winter.
Distribution and occurrence: Naturalised occasionally on the North Coast of NSW. Also in Qld. Native to the Americas.
NSW subdivisions: *NC
Weedy. Also known as Hemiadelphis polysperma. Hemiadelphis has only this one species and was split off from Hygrophila because of its 2 stamens and lack of hooks in the capsule but recent work suggests that the species belongs in Hygrophila.
Text by Karen Wilson (21 April 2008)
Taxon concept: Robyn Barker (pers. comm. August 2007)
APNI* Provides a link to the Australian Plant Name Index (hosted by the Australian National Botanic Gardens) for comprehensive bibliographic data
***The AVH map option provides a detailed interactive Australia wide distribution map drawn from collections held by all major Australian herbaria participating in the Australian Virtual Herbarium project.