Fimbristylis Vahl (Vahl 1805: 285)

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

5. Fimbristylis Vahl (Vahl 1805: 285) nom. cons.

Type species.

Scirpus dichotomus L. [= Fimbristylis dichotoma (L.) Vahl]

Description of the genus.

Annuals tufted or perennials with rhizomes. Culms scapose or subscapose, terete or 3-4-5-angular or ancipitous, variously pubescent to glabrous. Leaves spirally or distichously arranged, or reduced to a sheath, ligulate or eligulate; blade linear, filiform, or rarely ensiform, usually dorsiventrally compressed and canaliculate, often adaxially cellular-reticulate. Primary bracts short, not sheathing. Inflorescence variable usually capitate or anthelate. Spikelets few to numerous, or reduced to a single spikelet, mostly cylindric. Glumes usually spirally arranged, rarely distichous, deciduous, each subtending a bisexual floret. Perianth bristles absent. Stamens 1-3. Style 2-3-fid, often flattened with fimbriate margins when 2-fid; base distinct, thickened, deciduous. Nutlets obovoid, trigonous or biconvex and often variously ornamented, trigonous when style 3-fid, lenticular when style 2-fid, smooth, tuberculate or longitudinally ribbed, not transversely wrinkled.

Distribution and ecology.

Fimbristylis is a cosmopolitan genus ( POWO 2022). It grows on seasonally wet or damp sandy soils in grassland, woodland, riverbeds, and rice fields, also on rocks in shallow soil ( Browning and Goetghebeur 2017). Fimbristylis occurs throughout Madagascar; 17 species are known including e.g. Fimbristylis dichotoma (Fig. 17 ).

Figures

Figure 17. Fimbristylis dichotoma. A, B. Habit. C. Leaf sheath apex. D. Leaf apex. E. Spikelet. F, G. Glume, abaxial and lateral view. H. Floret. I. Nutlet. All from Brummitt 9546. Scale bars: A = 250 mm; B = 40 mm; C, E = 5 mm; D = 2 mm; F-I = 1 mm. Drawn by Jane Browning, reproduced with permission from the artist, originally published in Browning et al. (2020).