Molecular phylogenetics of the mainly Mediterranean genera Chaenorhinum, Kickxia and Nanorrhinum (Plantaginaceae, tribe Antirrhineae) with a focus on taxa in the Flora Iranica
5 February 2016
Yousefi, Nafiseh; Zarre, Shahin; Heubl, GüntherPlantaginaceae tribe Antirrhineae as revised by Sutton (1988) comprises about 30 genera that have undergone significant changes in taxonomy in recent years, many of which have yet to be assessed by detailed phylogenetic analyses, including Kickxia, Nanorrhinum and Chaenorhinum. To examine the monophyly, relationships and rank of Kickxia, Nanorrhinum and Chaenorhinum, we conducted phylogenetic analyses of nuclear ribosomal DNA internal transcribed spacer region (ITS) and chloroplast DNA (rpl32-trnL) sequence data of these three genera plus others, with a focus on the Flora Iranica. We sampled 22 species of Kickxia s. l. (16 of Kickxia s. str. and 6 of Nanorrhinum), 2 species of Anarrhinum, 12 species of Chaenorhinum, 19 representatives of nine additional genera of Antirrhineae, and several outgroup taxa representing other genera of Plantaginaceae. Parsimony and Bayesian analyses of the two datasets produced nearly congruent trees, although taxon sampling differed. Our results indicate that Chaenorhinum can be subdivided into two highly supported groups of species, partially matching two of the currently recognized sections in this genus. Albraunia and Holzneria are nested within the Chaenorhinum clade and should not be recognized as distinct genera. Two clades corresponding to Kickxia sect. Kickxia and Kickxia sect. Valvatae were also highly supported. Our data together with all other available evidence supports recognition of the clade comprising Kickxia sect. Valvatae at the genus level, as Nanorrhinum. In this respect, six names are transferred to Nanorrhinum. A diagnostic key to the seven genera of tribe Antirrhineae from the Flora Iranica is provided.