Biosystematic Studies of Carex (Cyperaceae) III. Phylogenetic Analyses of the Carex filipes complex (sect. Paniceae) in East Asia, with Reference to Morphology, Karyology and Taxonomy

Calex filipes (Cyperaceae) and its closely related species, which we tentatively refer to as the C. filipes complex, are greatly diverse morphologically. The closely allied species have often been included within C. filipes where they have been treated by as many as seven infraspecific taxa at the rank of variety. To better determin the taxonomic distinctness of the individual species and infraspecific taxa, we undertook molecular phylogenetic analyses of individuals of the C. filipes complex using the plastid DNA regions atpB-rbcL, rpl16-rpl16-rps3, rps16, matK, and trnL-trnL-trnF and nuclear DNA regions ITS and ETS. We compared the morphology of as many individuals as possible and determined the somatic chromosome number of some individuals to supplement missing information. It was concluded that the C. filipes complex comprises ten species, two varieties and one hybrid, i.e. C. arisanensis, C. curtispica, C. egena, C. filipes var. filipes, C. filipes var. tremula, C. kujuzana, C. xkurogii, C. kuzakaiensis, C. rouyana var. arakiana, C. rouyana var. rouyana, C. sohayakiensis, C. sparsinux and C. vaniotii. A diagnostic key to separate them, based on morphology, and chromosome numbers are presented. Two new species, C. curtispica and C. sohayakiensis and one new hybrid, C. xkurogii, are described. The origin of the hybrid is also discussed.