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 Machaerina Vahl (Vahl 1805: 238) Type species. Schoenus restioides Sw. [= Machaerina restioides Vahl] Description of the genus. Medium-sized to tall creeping rhizomatous or stoloniferous perennials. Culms scapose or with few nodes, flattened, angular, compressed or (sub)terete, sometimes septate. Leaves distichous, eligulate, blade ensiform to (sub)terete, sometimes septate, rarely reduced to a sheath. Primary bracts often leaf-like, sheathing. Inflorescence sometimes more or less pseudolateral, paniculate, main axis often sinuous, partial inflorescences sometimes capitately contracted. Spikelets many. Glumes 2-10 distichous, long-persistent, of increasing length, with (1-)2-4(-5) florets subtended by the larger glumes and enclosed by the wings of the next glume. Lower 1-2 floret(s) usually bisexual, upper floret(s) usually functionally male. Bristles absent or poorly developed, or up to 6, delicate, shorter than, to as long as the fruit, deciduous with the fruit. Stamens 3; filaments sometimes conspicuously elongated after anthesis. Style 3-fid, base not distinct, thickened, persistent, sometimes scabrid. Nutlets ovoid to oblong, terete to triquetrous, more or less 3-ribbed to winged, stipitate or sessile, beaked, smooth to rugose. Distribution and ecology. Machaerina occurs in Tanzania, Western Indian Ocean to Pacific, Tropical America ( POWO 2022 ). It grows in forest, shrubland, or grassland, along streams, in marshy areas or on rocks. Machaerina occurs in northern, northeastern, and southeastern Madagascar; four species are known including e.g. Machaerina flexuosa (Boeckeler) J.Kern (Fig. 10 ). Figure 10. Machaerina flexuosa . A . Habit ( x 2/3). B . Spikes from top of inflorescence ( x 3). C - D . Glume, abaxial and side view ( x 10). E . Flower ( x 10). F . Young flower ( x 8). G . Anther ( x 16). H . Nutlet ( x 16). A from Andriamahay & Rakotoarison 1969 ; B-G from Nusbaumer et al. 1103 ; H from Ranirison 642 . Drawn by Juliet Beentje, reproduced with permission from the artist, originally published in Hoenselaar et al. (2010) .