2013 Volume 64 Issue 3 Pages 137-147
In an effort to better understand phylogenetic relationships within Disporum (Colchicaceae), we conducted molecular analyses of 36 samples (13 species, two varieties and two forms) using the plastid sequences trnK, trnL-F, and atpB-rbcL. A strict consensus of the 72 most parsimonious trees obtained, which has an identical topology to the maximum likelihood trees, showed that a clade of D. smilacinum and D. viridescens was sister to the rest of the genus. In a clade composed of D. sessile, D. lutescens, D. nantouense, D. uniflorum, D. shimadae, and D. kawakamii, the former three species formed a subclade, while D. sessile var. sessile f. sessile from Kyushu, f. minus, var. micranthum, and D. lutescens were further grouped together. Disporum sessile var. sessile f. sessile from regions other than Kyushu, as well as D. nantouense, was excluded from this group. As D. lutescens differs greatly from D. sessile morphologically, they cannot be considered to be conspecific. Therefore, from a phylogenetic standpoint, two different species are possibly included under the name of D. sessile var. sessile f. sessile: one from Kyushu and the other from elsewhere. Disporum nantouense is possibly a variety of D. sessile. Disporum sessile var. micranthum Hatus., nom. nud. was validated.