【摘 要】
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A single small population of chasmophytic plants is described as Mojiangia oreophila,a monotypic genus in the subtribe Crepidinae,characterised by a unique combination of morphological features,in partic-ular densely long-papillose homomorphic achenes wit
【机 构】
：
China Forest Exploration and Design Institute in Kunming,Kunming,650200,Yunnan,China;Department of M
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A single small population of chasmophytic plants is described as Mojiangia oreophila,a monotypic genus in the subtribe Crepidinae,characterised by a unique combination of morphological features,in partic-ular densely long-papillose homomorphic achenes with five main ribs each accompanied by two sec-ondary ribs,coarse brownish pappus bristles,moderately many-flowered capitula,a small involucre with numerous outer phyllaries,perennial rosette herb growth and brown-woolly caudex and leaf axils.Molecular phylogenetic analysis detected that in the nrITS phylogeny M.oreophila forms a clade of its own in the Crepidinae;in the plastid DNA phylogeny it is nested in the clade formed by the hybrid-ogenous genus Faberia,the maternal ancestor of which comes from the Crepidinae and the paternal ancestor from the Lactucinae,where Faberia is placed in nrITS phylogenies.M.oreophila shares several morphological features with Faberia and also shares the expected chromosome number of 2n-16 with its hitherto unknown maternal ancestor.M.oreophila may therefore be a successor of the maternal ancestor of Faberia.Alternatively,cytonuclear discordance is to be assumed in Mojiangia,caused by chloroplast capture as a result of hybridisation and introgression with Faberia.
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