As the largest lineage in the tribe Gnaphalieae of Asteraceae, phylogenetic relationships within the Helichrysum - Anaphalis - Pseudognaphalium (HAP) remain poorly resolved. In this study we sequenced chloroplast genomes from 28 representative species from the HAP clade, performing comparative and phylogenetic analyses. Their chloroplast genomes ranged from 151,69 to 153,603 bp and possessed a typical quadripartite structure encoding 131-134 genes, including 87-89 protein-coding genes, 36-37 tRNA genes and 8 rRNA genes. The plastome data recognized the HAP into an early-diverging lineage and a large core clade. The latter was further separated into two subclades, namely core I and core II. Relatively small genomes with more insertion and fewer deletions were found in the early HAP lineage and Anaphalis taxa from core I. The small chloroplast genomes of the early lineage in the HAP clade potentially linked to their dry environmental adaptation in South Africa. The trn T-GGU gene was presented as pseudogenes in the early lineage and a subclade of core II but completely lost in the whole core I. As a distinct lineage within the HAP clade, Pseudognaphalium was characterized by the presence of an ycf 15 pseudogene with only 54 bp and the lack of hexanucleotide repetitions. The findings in this study enhance our understanding of the internal structure of chloroplast genomes in the HAP clade and provide valuable insights on the phylogenetics and plastome evolution of this clade.

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The first comprehensive plant checklist for the Bvumba massif, situated in the Manica Highlands along the Zimbabwe-Mozambique border, is presented. Although covering only 276 km 2 , the flora is rich with 1250 taxa (1127 native taxa and 123 naturalised introductions). There is a high proportion of Orchidaceae and Pteridophyta, with both groups showing a higher richness than for adjacent montane areas, which may be due to the massif's relatively high moisture levels as a result of frequent cloud cover. However, in contrast to other mesic montane regions in southern Africa, there are relatively few near-endemic or range-restricted taxa: there is only one local endemic, Aeranthes africana , an epiphytic forest orchid. This is likely to be an effect of the massif having limited natural grassland compared to forest, the former being the most endemic-rich habitat in southern African mountains outside of the Fynbos Biome. Six other near-endemic taxa with limited distribution in this portion of the Manica Highlands are highlighted. The high number of invasive species is probably a result of diverse human activities in the area. The main species of concern are Acacia melanoxylon , a tree that is invading grassland and previously cultivated land, the forest herb Hedychium gardnerianum which in places is transforming forest understorey with an adverse effect on some forest birds, and the woody herb Vernonanthura polyanthes which invades cleared forest areas after fire. Future botanical work in the massif should focus on a more detailed exploration of the poorly known Serra Vumba on the Mozambican side and on the drier western slopes. This will allow for a more detailed analysis of patterns of endemism across the Manica Highlands.

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