Phylogenetic analysis and taxonomic position of section Verrucosa of Panicum and its relationships with taxa of the Sacciolepis?Trichanthecium clade (Poaceae: Paniceae)

NICOLA, MARCELA; LIZARAZU, MABEL ANGELA; SCATAGLINI, M. AMALIA

PLANT SYSTEMATICS AND EVOLUTION

SPRINGER WIEN

Lugar: Viena; Año: 2015 vol. 301 p. 2247 - 2260

0378-2697

The new genus Kellochloa is proposed, on thebasis of morphological and molecular characters, to includetwo North American species of Panicum s.l., previouslyclassified in sect. Verrucosa: P. brachyanthum and P.verrucosum. Both species are annual, with decumbentculms branching divaricately at the lower nodes, and erectculms with terminal and axillary inflorescences. The spikeletsare pilose, with lower glume 1/6 to 1/4 the length ofthe spikelet, upper glume and lower lemma subequal, 3?5-nerved, the lower anthecium reduced to the lower lemma,and upper anthecium indurate, with bicellular microhairsand simple papillae evenly distributed all over the lemmaand palea. Molecular phylogenetic studies, analyzingplastid ndhF and rpoA sequences, confirmed that thesemorphological characters are differential. The phylogeneticposition and taxonomic features of the new genus areestablished and compared with Panicum s.str. and othertaxa of the Sacciolepis?Trichanthecium clade. Full synonymiesand descriptions, a distribution map, illustrationsof both species, and a key are provided. Two new combinationsare proposed. In addition, four African ungroupedspecies of Panicum s.l. were, for the first time, included inthe phylogenetic analysis to analyze their relationship withthe new genus and its positions in the Sacciolepis?Trichanthecium clade.