Coelachne madayensis (Poaceae: Pooideae: Isachneae), a new species from Kerala, India C. Pramod 1 , A.K. Pradeep 2 and J.F. Veldkamp 3 1 Department of Botany, Govt. Brennen College, Darmadam, Thalassery, Kerala, India 670 106 cpramod4@gmail.com (corresponding author) 2 Department of Botany, University of Calicut, Kerala, India 673 635 akpradeep1@rediffmail.com 3 Naturalis Biodiversity Center, National Herbarium of The Netherlands, Leiden University, P.O. Box 9514, 2300 RA Leiden, The Netherlands jan-frits.veldkamp@naturalis.nl ABSTRACT. A new species of Coelachne (Poaceae: Pooideae: Isachneae) from Madayippara in the Kannur District of Northern Kerala, India is described and illustrated. A key for the identifcation of the Indian congeners is provided. Keywords. Coelachne, India, Kerala, Poaceae Introduction The genus Coelachne R.Br. (Poaceae: Pooideae: Isachneae) is represented by 10 species distributed in the tropics and subtropics of the Old World (Mabberley, 2008; Clayton et al. 2006+). In India the genus is represented by 3 species, of which one species and one variety are endemic (Prakash & Jain 1984). In Kerala there are 2 species, viz. Coelachne infrma Buse [syn. C. simpliciuscula (Wight & Arn. ex Steud.) Munro ex Benth.] and C. perpusilla (Arn. ex Steud.) Thwaites, which usually occur in wet places (Sreekumar & Nair 1991). During a foristic survey in July 2011 of the lateritic plateau habitats of Northern Kerala, India, the frst two authors noticed a population of a very small species of Coelachne in the shallow seasonal pools and nearby wet areas. The specimens turned out not to belong to any described species of Coelachne, though they showed some similarity with the Indian species C. minuta Bor in their general habit, size, and organization of the spikelets. However, they differed in their non-tufted habit, absence of a ligule, ovate leafblades, fagleaves without a blade, racemes with up to 15 spikelets, lower forets with 0-nerved glumes and paleas, and 3 stamens. Therefore they are here described as a new species. 289 Gardens’ Bulletin Singapore 64(2): 289–292. 2012