Description: Tufted or rhizomatous annuals or perennials; annuals frequently amphicarpous (i.e. with basal spikelets hidden amongst leaf sheaths). Culms nodeless or 1(-3)-noded above the base, terete to triquetrous, glabrous.
Leaves mostly reduced to a mucro on a sheath, occasionally longer blade present; ligule membranous.
Aerial inflorescence pseudolateral, head-like or a single spikele, rarely shortly branchedt; lowest involucral bract culm-like, usually erect.Spikelets mostly sessile, many-flowered. Hypogynous bristles 2–6(-10), filiform and retrorsely scabrous, or flattened and irregularly plumose, or occasionally very reduced. Stamens 2 or 3. Style 2- or 3-fid. Basal (amphicarpous) spikelets present in some annual species.
Nuts lenticular or trigonous, smooth or transversely rugose. Basal spikelets with longer, 3-fid styles and larger nuts.
Distribution and occurrence: World: c. 50 species, cosmopolitan. Australia: 9 species (3 species endemic), all mainland States.
Previously included in Schoenoplectus. The species are commonly divided between two sections: sect. Schoenoplectiella (the small annual species, which are often amphicarpous, e.g. S. dissachantha and S. laevis) and sect. Actaeogeton (more robust annuals and rhizomatous perennials, not amphicarpous; e.g. S. lineolata, S. mucronata).
Text by KL Wilson (Nov 2015); edited KL Wilson (March 2019)
| ||Key to the species|| |
|1||Robust plants with culms usually 2–8 mm (rarely less) in diam.; culms triquetrous[; nuts smooth]||Schoenoplectiella mucronata|
|Slender plants with culms no more than 1 mm in diam., terete to subtrigonous||2|
|Nuts transversely rugose|
Back to 1
|3||Glumes 1.7–2.2 mm long, obtuse; stamens 2; plants tufted||Schoenoplectiella laevis|
|Glumes 3.8–4.5 mm long, acute; stamens 3; plants at least shortly rhizomatous|
Back to 2
|4||Glumes yellow-tinged, glabrous; stamens 2 or occasionally 3; nut with acutely angled transverse ridges, dark brown to black, subglobose to obovoid; hypogynous bristles present (rarely very short)||Schoenoplectiella dissachantha|
|Glumes red-tinged, ciliolate on margins; stamens 3; nut with broadly rounded transverse ridges, black, obovoid; hypogynous bristles absent|
Back to 2