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Species‐rich grasslands have high conservation value because they support diverse floral and faunal assemblages. Alpine grassland is an important and characteristic ecosystem of the Qinghai‐Tibet Plateau, but ca. 30 % has been severely degraded by the combined effects of climate change, human activity, overgrazing and rodent damage. One potential method to restore grassland diversity involves using hemiparasitic plants to modify the competitive relationships among neighboring species. A possible candidate is Pedicularis kansuensis, a hemiparasitic plant found in grasslands throughout the Qinghai‐Tibet Plateau, but more information on its host associations and its effects on surrounding vegetation is required to assess its suitability. Thus, we examined host associations of P. kansuensis by direct root excavation at a selected site on the Qinghai‐Tibet Plateau and found that haustoria formation is non‐randomly distributed among host species, with preferential bias for members of Poaceae, Rosaceae and Fabaceae. We also found that aboveground biomass of grasses and legumes was higher in quadrats from which the parasite had been removed than in intact controls, while the biomass of sedges and forbs was unaffected by parasite removal. However, removal significantly decreased plant species richness and Shannon–Wiener diversity. These results suggest that P. kansuensis modifies the competitive balance in grassland communities of the Qinghai‐Tibet Plateau, allowing for colonization by subordinate species and thereby enhancing species diversity and contributing to restoration of these degraded grasslands.

Gynaephora (Lepidoptera Erebidae: Lymantriinae) is a small genus, consisting of 15 nominated species, of which eight species are endemic to the Qinghai-Tibetan Plateau (QTP). In this study, we employed both mitochondrial and nuclear loci to infer a molecular phylogeny for the eight QTP Gynaephora spp. We used the phylogeny to estimate divergence dates in a molecular dating analysis and to delimit species. This information allowed us to investigate associations between the diversification history of the eight QTP species and geological and climatic events. Phylogenetic analyses indicated that the eight QTP species formed a monophyletic group with strong supports in both Bayesian and maximum likelihood analyses. The low K2P genetic distances between the eight QTP species suggested that diversification occurred relatively quickly and recently. Out of the eight species, five species were highly supported as monophyletic, which were also recovered by species delimitation analyses. Samples of the remaining three species (G. aureata, G. rouergensis, and G. minora) mixed together, suggesting that further studies using extensive population sampling and comprehensive morphological approaches are necessary to clarify their species status. Divergence time estimation results demonstrated that the diversification and speciation of Gynaephora on the QTP began during the late Miocene/early Pliocene and was potentially affected by the QTP uplift and associated climate changes during this time.

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