According to the recent molecular phylogenetic analyses by Gemeinholzer & al. (in Kilian & al. 2009) the subtribe Cichoriinae comprises six genera. Four of them, Arnoseris, Cichorium, Rothmaleria and Tolpis, were united already by Stebbins (1953) in his Cichoriinae, together with other, unrelated genera. Later classifications (Jeffrey 1966; Bremer 1994; Lack 2006) split the four genera apart again. To these four genera the analyses by Gemeinholzer & al. added (1) Erythroseris, a genus most recently established for two species from the Horn of Africa and Socotra island formerly placed in Prenanthes (Kilian & Gemeinholzer 2007), and (2) the localized SW North American monospecific Phalacroseris, with oblong-ellipsoid, unbeaked achenes and no pappus, which was revealed to branch off basally to all other taxa of the North American clade (Microseridinae s.l.) by Lee & al. (2003).
The six genera of the Cichoriinae form two subclades. In the first subclade Erythroseris is sister to Cichorium, while Phalacroseris branches off basally to both. In the second subclade Arnoseris is sister to Tolpis, while Rothmaleria branches off basally to both.
Two possible relationships have been suggested in the past for the monospecific SW Mediterranean genus Rothmaleria, namely either with Catananche and Hymenonema (Jeffrey 1966; Bremer 1994; Lack 2006) or with Cichorium (Stebbins 1953; Lack & al. 1980). The latter relationship is not only favoured by the molecular results, it is also supported by similar achenes, the non-aristate paleaceous pappus and the long collecting trichomes of the style (Lack & al. 1980).
The relationship of Arnoseris with Tolpis (Stebbins 1953; Jeffrey 1966; Bremer 1994) rather than with the Hypochaeris alliance (Lack 2006) is morphologically supported by short style branches with short trichomes, corolla tubes covered externally with crisped trichomes and has otherwise been supported by palynological data (Blackmore 1981) featuring small pollen grains with double rows of spines on the equatorial ridges.
The relationship of Tolpis with the Cichorium clade is only revealed in phylogenies of the nuclear marker (nrITS), whereas phylogenies of chloroplast markers reveal Tolpis (and Arnoseris; Gemeinholzer & al., in prep.) to cluster far away from the Cichorium clade (Whitton & al. 1995; Park & al. 2001). The deviating phylogenies of nuclear and the chloroplast markers, with different underlying modes of inheritance, can only be explained by reticulate evolution with an unknown parent preceding generic and species divergence of Tolpis and Arnoseris and resulting in subsequent chloroplast capture. The available molecular analyses have different samplings with respect to ingroup and outgroup taxa and result in slightly different placements of Tolpis, which is, however, most often closely related to Hyoseris and Urospermum. This may indicate former potential hybrid partners. The analyses of the most comprehensive sample was carried out by Gemeinholzer & al. (in prep.), where, in contrast to Park & al. (2001), T. staticifolia as well as T. capensis cluster right within the Tolpis group in both the nuclear and the chloroplast analyses, most likely as result of the broader taxa sampling.
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