Abstract: Amana is a group in the Liliaceae (s.s.) confined to central and eastern China, Japan and Korean peninsula. This group is similar to Tulipa L. by having leaves 2-5 basal or cauline, flower usually solitary, erect, stamens 6, 3 longer, and anthers basifixed, but differs in having 2-3(-4) opposite or verticillate bracts at the upper part of the flowering stem and a longer style as long as ovary. It has long been in dispute if the Amana group should be included in the genus Tulipa or treated as an independent genus of its own. Based on both herbarium and field observations on the Chinese taxa of Tulipa (s.l.), particularly those in the Amana group, a cladistic analysis of 18 species (including 3 species from Turkey) of Tulipa was carried out in the present work. Twenty-eight morphological characters were used in unweighted pair-group method using the maximum parsimony (MP) tree construction executed with PAUP 4.0b4a program. The results show that Tulipa (s.l.) is not a monophyletic group but split into two clades: one is Amana group, and the other comprises Orithyia, Eriostemones, Leiostemones and Tulipanum. Our unpublished data of ITS and trnL-F sequences in 19 species representing five sections of Tulipa (s.l.) also show that sect. Tulipanum, sect. Leiostemones, sect. Eriostemones and sect. Orithyia form one clade, whereas the Amana group and Erythronium form another clade. The Amana group is thus better treated as an independent genus.

Key words: Liliaceae, Tulipa, Amana, morphological character, cladistic analysis.