Isolepis
Prodr., 221. 1810.
| Taxon | Illustrator ⠉ | |
|---|---|---|
 | Isolepis carinata Isolepis pseudosetacea Isolepis cernua Isolepis setacea Oxycaryum cubense | Amanda Humphrey Amanda Humphrey Amanda Humphrey Amanda Humphrey Amanda Humphrey |
Herbs, annual or perennial, cespitose, rhizomatous or not, smooth, glabrous. Culms terete. Leaves all basal; sheaths green to stramineous, sometimes reddish proximally; ligules absent; blades rudimentary to exceeding culms. Inflorescences terminal, sometimes pseudolateral, capitate or solitary spikelet; spikelets 1–3 (–15); involucral-bracts 1 (–2), spreading to erect, like foliage leaf-blades. Spikelets: scales 8–25, spirally arranged, each subtending flower. Flowers bisexual; perianth absent; stamens 1–3; styles linear, 2–3-fid, base persistent, sometimes slightly enlarged. Achenes biconvex or trigonous, papillose or longitudinally ribbed.
Distribution
Worldwide in cool-tropical and temperate regions, especially Africa and Australia
Discussion
Species 69 (4 in the flora).
Isolepis is difficult to delimit on a worldwide basis and has been included in Scirpus in the broad sense. Data derived from embryologic, genetic, and other studies led in recent years to the acceptance of Isolepis as a distinct genus (J. J. Bruhl 1995; P. Goetghebeur 1998; A. M. Muasya et al. 2001).
Selected References
None.
Key
| 1 | Spikelets with scales markedly gibbous, often clasping shed achenes, colorless to stramineous, or orangish, or greenish; achenes acutely equilaterally trigonous; leaf sheaths green to stramineous or brown. | > 2 |
| 1 | Spikelets with scales neither gibbous nor clasping shed achenes, usually at least partly orange- to red-brown or blackish; achenes compressed-trigonous or thickly plano-convex; leaf sheaths usually reddish proximally. | > 3 |
| 2 | Scales from middle of spikelet 1.8–2 mm, with awns 0.2–0.5 mm; achenes 1–1.5 mm. | Isolepis carinata |
| 2 | Scales from middle of spikelet 1–1.2 mm, with mucros to 0.1 mm; achenes 0.7–0.9 mm. | Isolepis pseudosetacea |
| 3 | Achenes papillose, not ribbed; culms, leaves, and involucral bracts not orange-punctate or sheaths sparsely so. | Isolepis cernua |
| 3 | Achenes not papillose, prominently longitudinally ribbed at 10X and minutely transversely ridged at 20–30X; culms, leaves, and involucral bracts orange-punctate at 10– 15X. | Isolepis setacea |
"shortened" is not a number.