The phylogeny of the chloridoideae (Gramineae): a cladistic analysis

One hundred of morphological characters of 69 species (representing 52 genera and all tribes and sub-tribes of the subfamily Chloridoideae of Gramineae) are used to reconstruct the phylogeny for the Chloridoideae. Cladistic analysis show that the monophyly of Chloridoideae and its origination from danthonoid group aresupported. Five clades are found in correlation with traditional classification systems. Clade A comprises 2 genera of Pappophoreae, clade B 5 genera of Eragrostideae, clade C 6 genera of Eragrostideae, clade D 9 genera of Eragrostideae, and clade E comprises 8 genera of Eragrostideae, 9 genera of Chlorideae, and 1 genus of leptureae. The two largest tribes Eragrostideae and Chlorideae turn out to be polyphyletic. The chlorideae affinity of Leptureae is substantiated in the cladistic study. The basal tribe Pappophoreae may provide a link between the chloridoids and the danthonoids. A pattern of segregation of species from Old World to New World is evident in several clades. These results provide a framework for further studies at the supra-generic levels moving toward to a comprehensive systematic treatment of the Chloridoideae.