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Six subtropical montane forest Kaunia spp. are remarkable for their superficial morphological similarity. We aim to explore different sources of data to clarify species delimitation in this complex of Kaunia. Morphological variation and environmental data of the species of the complex were assessed by using multivariate morphometric analyses. We performed a species distribution modelling approach applying BIOMOD2. Morphological quantitative traits allowed discrimination of some species in the complex. These Kaunia spp. have statistically different potential distributions, although some similarities between species in terms of climatic space were found. The species with the most similar climatic space were K. saltensis and K. lasiophthalma. The biogeographical context that could have affected the distribution of these two species is discussed. The results of our integrative study confirm the discrimination of three species, K. lasiophthalma, K. rufescens and K. saltensis, but the other three, K. arbuscularis, K. longipetiolata and K. uber, are here regarded as a single entity. [ABSTRACT FROM AUTHOR]

Premise of research. Glands on the styles of Asteraceae are uncommon. They are reported in Kaunia for the first time. Glandular trichomes of plants are involved in the synthesis of secondary metabolites. In Kaunia, secondary compounds with medicinal cytotoxic, antitumor activity, and sensitizing capacity were previously identified. In this frame, a deeper knowledge of glandular trichomes could shed light on the productivity of medicinal substances in Kaunia. The potential taxonomic and ecological value of stylar glandular trichomes in Kaunia is also explored together with trichome secretion phases throughout the floral developmental stages. Methodology. Herbarium specimens and flowers fixed in FAA of 10 species of Kaunia were analyzed. Flowers in different developmental stages were studied to observe the secretory phases of stylar trichomes. A histochemical test was carried out to detect sesquiterpene lactones on stylar glandular trichomes. Pivotal results. Glandular trichomes were detected on the ventral face of style branches in eight species of Kaunia in all floral stages analyzed. The stylar trichomes observed were mostly found in secretory or early postsecretory phases in the most immature floral stages. The histochemical test in stylar trichomes was positive for sesquiterpene lactones. Conclusions. The presence of stylar glandular trichomes provides valuable new evidence for the identification and characterization of Kaunia. Within the Eupatorieae, the presence of stylar glandular trichomes could be interpreted as taxonomically valuable at the rank of genus. Our finding of sesquiterpene lactones is in agreement with the presence of Guaianolides and Germacranolides previously isolated in Kaunia. Apparently, the secretion of trichomes is completed before the opening of the corolla. The glands on styles of Kaunia could be the most internal barrier to herbivores that could flank outer floral structures during pollen and style development. [ABSTRACT FROM AUTHOR]