Actinoschoenus Benth. (Bentham 1881: 33)

Rasaminirina, Fitiavana & Larridon, Isabel, 2023, The genera of Cyperaceae of Madagascar, Plant Ecology and Evolution 156 (3), pp. 276-310 : 276

3. Actinoschoenus Benth. (Bentham 1881: 33)

Type species.

Actinoschoenus filiformis (Thwaites) Benth. [= Actinoschoenus aphyllus (Vahl) Larridon]

Description of the genus.

Small to medium-sized, tufted, shortly rhizomatous or stoloniferous perennials. Culms scapose, smooth, tufted, more or less 4-angular, bases covered by closed leaf sheaths. Leaves ligulate if present, blade very short, almost reduced to a sheath. Primary bracts small, not very conspicuous not sheathing. Inflorescence terminal, capitate. Spikelets 2 or many. Glumes 4-7 distichous, deciduous glumes, of increasing length; rachilla internodes short, somewhat elongated between the florets. Floret(s) 1(-2), subtended by the penultimate larger glume, enclosed by the wings of the next glume, bisexual. Perianth bristles absent. Stamens 3. Style deeply 3-fid, style base distinct, thickened, deciduous. Nutlets obovoid, trigonous, more or less 3-ribbed, surface smooth to slightly tuberculate.

Distribution and ecology.

Actinoschoenus occurs from West-Central Tropical Africa to Zambia, Western Indian Ocean, Sri Lanka to southern China and Australia ( POWO 2022). It grows in open woodland on dry sandy areas ( Browning and Goetghebeur 2017), wetlands, swamps, sands and wet rocks, water’s edge, forest, to 800 m elevation ( Chermezon 1937). A single species of Actinoschoenus , i.e. Actinoschoenus aphyllus (Vahl) Larridon (Fig. 15 ), occurs throughout Madagascar.

Figures

Figure 15. Actinoschoenus aphyllus. All photos taken in Andrainjato, Taolagnaro District, Anosy Region by Andriambolantsoa Rasolohery (https: // www. inaturalist. org / observations / 145409565), reproduced with permission from the photographer.