Electronic Flora of South Australia
Electronic Flora of South Australia
Census of SA Plants, Algae & Fungi
Identification tools

Electronic Flora of South Australia genus Fact Sheet

Family: Cyperaceae

Citation: R. Br., Prod. Fl. Nov. Holl. 224 (1810).

Derivation: Greek helos, heleos, a marsh; chairo, I delight in.

Synonymy: Not Applicable

Common name: Spikerushes.

Annual or perennial herbs, often stoloniferous, leafless; stems slender or stout, tufted or in a linear series along slender rhizomes; leaves represented by 1 or more sheaths at the base of the stems.

Spikelets solitary, terminal, erect, ebracteate, few- to many-flowered, with a bract continuing the stem; glumes imbricate all round the rhachilla; flowers bisexual; hypogynous bristles filiform or very slender, usually retrorsely barbellate, to 10 in number or absent; style 3-fid (sometimes 2-fid in other areas); stamens 1-3.

Nut crowned by the persistent enlarged base of the style.

Distribution:  About 200 species, cosmopolitan. (S.T. Blake (1939) Proc. R.Soc. Qld 50, 12:88-132). Has been spelt Heleocharis by some early authors.

Biology: No text

Key to Species:
1. Stems 4-12 mm wide, prominently transversely septate
E. sphacelata 8.
1. Stems not more than 4 mm wide, not septate.
2. Leaf sheaths hyaline, scarious or withered at the apex, not mucronate; hypogynous bristles much smaller than the nut or 0.
3. Plants not producing tubers; spikelets ovate to linear, often setting fruit; glumes 2-2.2 mm long
E. pusilla 7.
3. Plants producing tubers; spikelets lanceolate to linear, rarely maturing; glumes c. 3 mm long or more
E. atricha 2.
2. Uppermost leaf sheaths prominently thickened at the mouth; hypogynous bristles about as long as or longer than the nut.
4. Nut trigonous; leaf sheath oblique at the mouth, usually not mucronate; style 3-fid
E. gracilis 4.
4. Nut biconvex; leaf sheath truncate and mucronate at the top or, if oblique, then the style 2-fid.
5. No creeping rhizome; nut with rib-like margins (sometimes faintly so).
6. Leaf sheath oblique
E. geniculata 3.
6. Leaf sheath truncate and mucronate
E. pallens 5.
5. Rhizome creeping; margins of nut not thickened.
7. Culms terete or nearly so
E. acuta 1.
7. Culms strongly flattened
E. plana 6.

Author: Not yet available

Disclaimer Copyright Disclaimer Copyright Email Contact:
State Herbarium of South Australia
Government of South Australia Government of South Australia Government of South Australia Department for Environment and Water