Common name: Frogbit
Hydrocharis dubia (Blume) Backer APNI*
Description: Aquatic perennial with emergent and floating leaves; stolons rooted in shallow water, floating across deeper water.
Leaves with lamina broad-ovate to ± circular, to 6 cm long and nearly as wide, base cordate to reniform or truncate; petiole to 12 cm long.
Flowers c. 2–3 cm diam., erect and aerial. Spathe 1–2.5 cm long. Sepals 4–5 mm long, 2–3 mm wide, green; petals 10–15 mm long, rounded, white, yellow at the very base. Male flowers arising 1–4 together on short pedicels from a peduncled spathe. Female flowers arising singly on a pedicel 1–8 cm long from a sessile spathe.
Fruit 5–10 mm long, about half as wide; seeds 1–1.5 mm long, tuberculate.
Distribution and occurrence: Grows in small shallow freshwater bodies or swamps; uncommon, north from the Clarence R.
NSW subdivisions: NC
Other Australian states: Qld
This species has been placed sometimes under the genus Limnobium; however, the reference Les, D.H, Moody, M.L. and Soros, C.L. (2006) A reappraisal of phylogenetic relationships in the Monocotyledon family Hydrocharitaceae (Alismatidae). Aliso 22, pp 211-230, supports keeping this species in the genus Hydrocharis rather than in Limnobium.
Text by S. W. L. Jacobs (1993); notes added by Louisa Murray and Peter G. Wilson (May 2011); edited KL Wilson (Nov 2011).
Taxon concept: Flora of NSW 4 (1993)
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.