Nuclear ITS and AFLPs provide surprising implications for the taxonomy of Tephroseris longifolia agg. and the endemic status of T. longifolia subsp. moravica

Abstract

The proportion of endemic taxa is a frequently used measure for assesment of biodiversity hotspots within the Carpathians. For confirming of an endemic status of a taxon, a thorough evaluation using modern tools of plant systematics is desirable. Tephroseris longifolia subsp. moravica has been considered to be a Western Carpathian endemic, but a previous study of morphological and genome size differentiation within the T. longifolia agg. showed that its endemic position is controversial. Therefore, in this study we aimed to detect genetic variability and evolutionary relationships within the T. longifolia agg. using nuclear ITS sequences and highly variable AFLPs on 38 populations covering the distribution range of the aggregate. Additionally, we analysed 22 populations of other putatively related species (T. aurantiaca, T. capitata, T. crispa, T. integrifolia and T. papposa). Genetic analyses proved that T. longifolia agg. is genetically well differentiated, but the results contradict the current taxonomic concept. Tephroseris longifolia aggregate, as defined here, comprises T. longifolia, T. crispa, T. pseudocrispa, T. tenuifolia and T. italica. Within T. longifolia, two subspecies can be recognised, namely T. l. subsp. longifolia and T. l. subsp. moravica. Furthermore, AFLPs confirm the close relationship of Pannonian and one Croatian populations to T. l. subsp. moravica. Therefore, we assume that T. l. subsp. moravica should not be considered a Western Carpathian endemic and most probably migrated to the Western Carpathian area during the post-glacial period.