Cycnogeton dubium (R.Br.) Mering & Kadereit

Diversity Phylogeny Evol. Monocotyledons 73 (2010) APNI

Taxonomic status:Accepted

Occurrence status:Present

Establishment means:Native

Threat status:Victoria: rare (r)

Similar to Cycnogeton procerum but plants more slender; tubers plumper, near-globular to ellipsoid or broad-obovate, only 1–4 times as long as broad; leaves 31–75 cm long, 3.5–15 mm wide, the sheaths not meeting across the face of the blade, each sheath equal to about one-quarter to one-third of the leaf width (in cross-section c. 3 cm below the sheath summit); scape at fruiting 23–67 cm long, 13–25 mm diam.; mature fruits loosely touching or separate, c. (15–)39–250 per infructescence, 8.3–10.5 mm long, 5.5–8.8 mm wide, variable in outline but very distinctive with free (occasionally minutely attached at the base), erect to semi-outspread, mature carpels; mature carpels 1–6, lacking ridges or with inconspicuous broad-convex dorsal ridges, each carpel ± lanceoloid, circular in cross-section; all (2–)3(–6) carpels mature or often some abort. Fruits (Oct.–)Nov.–Mar.

MuF, MuM, RobP, VRiv, Wim. Also WA, NT, Qld, NSW. Occurs in still ephemeral fresh water to 50 cm deep, in swamps creeklets and floodplains, typically in Eucalyptus largiflorens/Muehlenbeckia florulenta sites.

Collections from northern Australia usually have ± cylindric leaves tapered from sheath to apex, and larger fruits up to 21 mm long. They have been referred to a separate species, Triglochin pterocarpa W.Fitzgerald, but gradations indicate that this specific distinction is not warranted.

Created by: Andre Messina, 2014-07-22
Updated by: Val Stajsic, 2019-02-11
Hero image
Distribution map
life Life
kingdom Plantae
phylum Tracheophyta
superorder Lilianae
order Alismatales
family Juncaginaceae
genus Cycnogeton
Higher taxa


Source: AVH (2014). Australia's Virtual Herbarium, Council of Heads of Australasian Herbaria, <>. Find Cycnogeton dubium in AVH ; Victorian Biodiversity Atlas, © The State of Victoria, Department of Environment and Primary Industries (published Dec. 2014) Find Cycnogeton dubium in Victorian Biodiversity Atlas
  Bioregion Occurrence status Establishment means
Murray Mallee present native
Wimmera present native
Victorian Riverina present native
Robinvale Plains present native
Murray Fans present native

State distribution

Distribution map
Western Australia
Northern Territory
South Australia
New South Wales