On the Taxonomic Status and the Phylogenetic Relationships of Some Unispecific Mediterranean Genera of Compositae-Anthemideae II. Daveaua, Leucocyclus and Nananthea

Abstract

Sequences of the nrDNA internal transcribed spacer (ITS) region were analysed for 113 representative species of 59 genera of Compositae-Anthemideae to ascertain the systematic position of the three unispecific Mediterranean genera Daveaua, Leucocyclus and Nananthea. Daveaua anthemoides is found to be a member of a well supported clade of genera around the closely-knit Leucanthemum group, being a candidate (together with Heteromera and Otospermum) for a sister-group of this assemblage. For Leucocyclus formosus, which was considered to be closely related to Anacyclus due to its dorsiventrally flattened achenes, a position close to or even among representatives of Achillea is demonstrated, corroborating alleged relationships suggested by the flavonoid complements of these genera. Nananthea perpusilla, hitherto considered to be close to Anthemis due to its tetrasporic embryo sac development, is found to be more closely related to Tripleurospermum, which also shares the tetrasporic embryo sac and the indumentum of basifixed hairs.