Rhizome much-branched, glabrous except at the tips. Fronds 1–12 cm long, clustered. Stipes glabrous or scaly. Leaflets narrowly oblanceolate to cuneate, 1–12 mm long, 1–5 mm wide, arranged unequally with 2 leaflets spreading and 2 ± porrect, glabrous or scaly; outer margin entire, flat to rounded. Sporocarps in clusters; stalks 1–2 mm long, unbranched, glabrous; conceptacles 2.5–3 mm long, scaly, distinctly ribbed; upper surface concave; upper basal tooth prominent; lower basal tooth absent; apex of the stalk forming a less prominent, tooth-like protuberance.
Endemic to coastal and inland localities in southern W.A., N.T., S.A., Qld, N.S.W., A.C.T. and Vic.
N.T.: Napperby Station, T.S. Henshall 1019 (DNA).
S.A.: entrance to Wilpena Pound, S.T. Blake 16879 (BRI).
Qld: Serpentine Creek, 11 km NE of Brisbane, L. Durrington 546 (BRI).
N.S.W.: Cobar township, E.J. McBarron 18421A (NSW).
Vic.: Lake Powell, 16 km SE of Robinvale, A.C. Beauglehole 56162 (MEL).
G.R. Sainty & S.W.L. Jacobs, Waterplants of New South Wales 295 (1981), as M. angustifolia ; B.D. Duncan & G. Isaac, Ferns and Allied Plants of Victoria, Tasmania and South Australia 221, fig. 21.4 (1986), as Marsilea sp.; S.B. Andrews, Ferns of Queensland 242, fig. 22.1C (1990), as M. angustifolia; D.L. Jones, Muelleria 8(1): 66, fig. 1 (1993); P.M. McCarthy (ed.), Flora of Australia 48: 170, fig. 56C–D (1998).
Jones, D.L. (1993). A new species of Marsilea L. (Marsileaceae) from Australia. Muelleria 8(1): 65–67.
Jones, D.L. (1998). Marsileaceae, in McCarthy, P.M. (ed.), Flora of Australia 48: 166–173, 707. (ABRS: Canberra/CSIRO Publishing: Collingwood).
Author - D.L. Jones
Contributor - A.M. Wheeler (editorial assistance August 2022); P.G. Kodela (ed., 13 April 2023)
Editor -
Acknowledgements -
Cite this profile as: D.L. Jones. Marsilea costulifera, in (ed.), Flora of Australia. Australian Biological Resources Study, Department of Climate Change, Energy, the Environment and Water: Canberra. https://profiles.ala.org.au/opus/foa/profile/Marsilea%20costulifera [Date Accessed: 03 April 2025]