Spikelet Structure in Cypereae (Cyperoideae-Cyperaceae)

Abstract

This work provides an analysis of the spikelet structure in Cypereae, and their taxonomic and phylogenetic implications. The main variations in the Cypereae spikelets are seem in: number and phyllotaxis of the glumes, presence/absence of empty glumes, glume morphology, rachilla internode length, prophyll development, flower structure and structure of the dispersal unit. Consistently with the latest molecular phylogenies proposed for Cypereae, our results support the division of this tribe into two groups with spikelet characters more or less typical: the Cyperus and the Ficinia clades. Within the Cyperus clade, the existence of spikelets with convergent characters among the different taxa supports the inclusion of all this clade taxa within one wide genus Cyperus, just as the current phylogenetic hypotheses proposed for the group.