A reappraisal of the conservation status of the indigenous New Zealand vascular plant flora is presented. The list comprises 792 taxa (34% of New Zealand's total indigenous vascular flora) in the following categories: Extinct 4 taxa, Acutely Threatened 122 taxa (comprising 47 taxa Nationally Critical, 54 Nationally Endangered, 21 Nationally Vulnerable), Chronically Threatened 96 taxa (comprising Serious Decline 26 taxa, Gradual Decline 70 taxa), At Risk 499 taxa (comprising Sparse 126 taxa, Range Restricted 373 taxa), Non-resident Native 26 taxa (comprising Vagrant 16 taxa, Colonist 10 taxa), and Data Deficient 45 taxa. A further 208 plants are listed as Taxonomically Indeterminate, being those which might warrant further conservation attention once their taxonomic status is clarified. A further 31 named taxa and 18 rated as Taxonomically Indeterminate, and previously considered to be threatened and/or uncommon, are removed from this updated listing. A concordance of plant names is provided. The lists presented use a new threat classification system developed by the New Zealand Department of Conservation for sole use within this country. This paper represents the first time the entire known indigenous vascular flora has been assessed from a conservation perspective since the mid 1970s. A brief analysis of the patterns of rarity exhibited by the taxa listed is presented.

Question Rare and threatened species are a common focus of natural area protection, but selecting sites to protect them must be balanced against other conservation objectives. Using a series of wetlands as a case study, we ask: (i) will protecting sites based on species rarity capture all critical community types; (ii) do rare plant species occur in rare environments; and (iii) will safeguarding large wetlands protect taxonomic and functional richness of rare and threatened species? Location Southern New Zealand. Methods We used lists of vascular plant species from 118 wetlands (66 fens, 35 bogs and 17 marshes). The resulting species lists included 29 rare and threatened species. Nine functional attributes of the rare and threatened species were compiled. Species assemblages were ordinated using non‐metric multidimensional scaling. Permutational multivariate ANOVA tested for a difference in assemblages between wetlands with or without rare and threatened species. Wetlands were classified according to a rare environment scheme. SLOSS (single‐large‐or‐several‐small) accumulation curves determined whether species and functional richness of rare and threatened species were best captured by groups of small or large wetlands. Results Wetlands with rare and threatened species supported species assemblages, which were different from those without rare or threatened plant species. Rare and threatened species were not associated with rare environments. The presence or richness of rare and threatened species was not associated with wetland size. SLOSS analyses revealed that small wetlands were critical for capturing rare and threatened species and their functional richness. Conclusions Prioritizing wetlands with rare and threatened plant species will not meet other conservation objectives, such as the preservation of all critical community types, rare environments or large wetlands. Networks of small wetlands will be necessary to safeguard rare and threatened plant species. Complementary objectives targeted at wetlands of varying size will be necessary to protect the full range of biodiversity and ecosystem services that wetlands offer.

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Question Is there evidence for similar community assembly processes in two geographically disjunct examples of a rare alpine ecosystem? Location Two alpine granite gravel fields 610 km apart along a fault line in western South Island, New Zealand – the Lookout Range and Mt Titiroa. Methods Plot‐based vascular plant composition and traits for 86 species (height, seed length, leaf size and nutrient concentrations) were used to examine community structure reflecting assembly processes. We examined species richness, trait values averaged across species and plots, relationships between trait pairs using standardized major axis (SMA) regression and phylogenetically independent contrasts (PIC), relationships between abundance and trait values, and functional diversity indices against null models. Lastly, we partitioned taxonomic, functional and phylogenetic diversity within and across alpine ranges. Results Functional and phylogenetic turnover of diversity between the two locations was low (2.9% and 6.3%, respectively) relative to turnover of taxonomic diversity (75%). Species‐level traits were similar between the two locations, except leaf P, which was higher at Mt Titiroa. Plot‐level average traits were all significantly higher on Mt Titiroa. Relationships between species‐level traits were typically non‐significant at both locations, or significant only at a single location. In contrast, relationships between plot‐level trait values were frequently significant and consistent across the two locations. At both locations, dominant species had a narrow range of similar trait values, while rare species had a wide range of values. Within plots, we found both trait convergence and divergence. Associations of trait values among dominant and rare species were largely non‐random but inconsistent between the two locations. Conclusions The two locations had a similar pool of trait values but often differed in how those traits were assembled. Results demonstrate that dominant species are subject to rigorous filters during community assembly leading to trait convergence, but rare species contributed to trait diversity and trait divergence. Models of community assembly can often predict traits of dominant species but must consider the importance of rare species as a source of local trait diversity, even in species‐poor communities under severe environmental conditions.

Twelve additional records of indigenous vascular plants and 25 naturalised plant records are added to the flora of Stewart Island. The majority of the new naturalised plant records come from Halfmoon Bay. Observations on the distribution and abundance of Gunnera tinctoria on Stewart Island are given, as this species is considered to pose a significant threat to indigenous biodiversity.