The genera of Cyperaceae of Madagascar Author Rasaminirina, Fitiavana https://orcid.org/0000-0003-0162-7975 University of Antananarivo, Antananarivo, Madagascar Author Larridon, Isabel https://orcid.org/0000-0003-0285-722X Kew Madagascar Conservation Centre, Antananarivo, Madagascar & Royal Botanic Gardens, Kew, Richmond, UK i.larridon@kew.org text Plant Ecology and Evolution 2023 2023-08-29 156 3 276 310 http://dx.doi.org/10.5091/plecevo.98847 journal article http://dx.doi.org/10.5091/plecevo.98847 2032-3921-3-276 BC5E6BD70022518ABF185FC3C18147CE 1. Isolepis R.Br. (Brown 1810: 221) Type species. Scirpus setaceus L. [= Isolepis setacea (L.) R.Br.] Description of the genus. Small to more rarely medium-sized tufted annuals or mat-forming perennials; rhizome more rarely creeping, rhizomatous or stoloniferous. Culms scapose or with few to many nodes. Leaves eligulate, of a minute lobe or elongated to form a linear blade often much reduced. Primary bracts leaf-like or short, not sheathing, lowermost bract often erect. Inflorescence often pseudolateral, capitate, rarely anthelate. Spikelets few to many or reduced to a single spikelet. Glumes with few to many usually spirally arranged (rarely distichous), mostly deciduous glumes, each subtending a floret. Floret bisexual. Perianth bristles absent. Stamens 1-3; filament ribbon-like, anther crested with minute spikes. Style deeply 2-3-fid; base not distinct, not or slightly thickened, persistent. Nutlets mostly obovoid, thick lenticular to (rounded) trigonous, often 3-ribbed, beaked, surface with various ornamentations. Distribution and ecology. Isolepis is a cosmopolitan genus ( POWO 2022 ). It grows in temporary and permanently wet areas. In Madagascar, Isolepis is known from the north and the Central Highlands; four species are known including e.g. Isolepis fluitans (L.) R.Br. (Fig. 21 ). Figure 21. Isolepis fluitans . A . Habit. B . Leaf sheath. C . Spikelet. D . Rachilla, apical glume attached. E . Glume, lateral view. F . Floret. G , H . Nutlet, abaxial and apical view. All from Iversen & Martinsson 89195 . Scale bars: A = 40 mm; B-H = 1 mm. Drawn by Jane Browning, reproduced with permission from the artist, originally published in Browning et al. (2020) .