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 range Afganistan to S. China and Peninsula Malaysia, Taiwan.
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). Native range updated by K.L.Gibbons 24 June 2020 [POWO (2019). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet; http://www.plantsoftheworldonline.org/ Retrieved 24 June 2020].
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.