Revision of the group previously known as Panicum L. (Poaceae: Panicoideae) in Madagascar

Abstract

Vorontsova, M.S. (2018). Revision of the group previously known as Panicum L. (Poaceae: Panicoideae) in Madagascar. Candollea 73: 143–186. In English, English and French abstracts. DOI: http://dx.doi.org/10.15553/c2018v732a1Panicoid grasses are ubiquitous across Madagascar, yet no complete and modern taxonomic framework has so far been attempted. This paper aims to establish and record species boundaries in the group previously recognised as the genus Panicum L. (Poaceace, Panicoideae), with simple panicoid spikelets and open panicle-like inflorescences. All specimens held at the K, P, and TAN herbaria were revised in addition to field work throughout the island. Species concepts were reconciled with those in tropical Africa. Recent phylogenetic research in Panicum s.l. has been incorporated and several species have been placed in Adenochloa Zuloaga, Trichanthecium Zuloaga & Morrone, and Urochloa maxima (Jacq.) R.D. Webster. Further species outside the Panicum s.s. clade will be ultimately transferred to other genera pending further research. A treatment of 32 species is presented, including an identification key, synonymy and typification for all names applied to specimens collected in Madagascar, species descriptions, illustrations, distribution maps, and full specimen citations. Twenty species (63%) are endemic to Madagascar and the nearby islands. Data on natural occurrence in Madagascar are presented but these are still tentative. Nineteen names are placed in synonymy for the first time; 38 lectotypes are designated.