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A reappraisal of the conservation status of the indigenous New Zealand vascular plant flora is presented using the 2008 version of the threat classification system developed for the New Zealand Department of Conservation. The list comprises 897 taxa (38% of New Zealand's total indigenous vascular flora) in the following categories: Extinct--6 taxa, Threatened--180 taxa (comprising 91 Nationally Critical taxa, 45 Nationally endangered, and 44 Nationally Vulnerable), At Risk--651 taxa (comprising 83 Declining, 6 Recovering, 20 Relict, and 542 Naturally Uncommon taxa), 25 taxa listed as either Vagrant (12) or Coloniser (13), and 35 as Data Deficient. a further 171 plants are listed as taxonomically indeterminate, being those which might warrant further conservation attention once their taxonomic status is clarified. Forty-four recognised taxa and 26 plants rated as taxonomically indeterminate, and previously considered to be threatened and/or uncommon, are removed from this updated listing. A brief analysis of the patterns of rarity exhibited by the listed taxa is presented. Overall, the conservation status of the New Zealand indigenous vascular plant flora is worsening, with 7.6% of this flora now regarded as threatened with extinction. A concordance of plants names from the 2004 listing is provided. [ABSTRACT FROM AUTHOR]

A revision of the New Zealand endemic Lepidium oleraceum and allied species is presented. Sixteen species are recognised, 10 of these are new. The new species are segregated on the basis of morphological characters supported by molecular data obtained from three DNA markers (two rDNA and one cpDNA). One species, Lepidium castellanum sp. nov., is endemic to the Kermadec Islands where it is sympatric with Lepidium oleraceum. The North Island of New Zealand supports four species, with two of them, Lepidium amissum sp. nov. and Lepidium obtusatum, now extinct. The South Island supports six species, that, aside from Lepidium banksii, Lepidium flexicaule and Lepidium oleraceum, are all confined to the south-eastern half of the island (Lepidium aegrum sp. nov., Lepidium crassum sp. nov. and Lepidium juvencum sp. nov.). One of these, Lepidium juvencum sp. nov., extends to Stewart Island. The Chatham Islands support six species (Lepidium flexicaule, Lepidium oblitum sp. nov., Lepidium oleraceum, Lepidium oligodontum sp. nov., Lepidium panniforme sp. nov., and Lepidium rekohuense sp. nov.), one of which, Lepidium oligodontum sp. nov., extends to the Antipodes Islands group. The remote, subantarctic Bounty Islands group supports one endemic, Lepidium seditiosum sp. nov., which is the only vascular plant to be recorded from there. Lepidium limenophylax sp. nov. is known from islands off the south-western side of Stewart Island/Rakiura, The Snares and Auckland islands. Lepidium naufragorum, although not related to Lepidium oleraceum and its allies, is also treated because populations with entire leaves are now known. Typification is undertaken for Lepidium banksii, Lepidium oleraceum, Lepidium oleraceum var. acutidentatum, var. frondosum and var. serrulatum.

New Zealand is diverse in alpine and subalpine environments, a consequence of Late Tertiary tectonic and climatic change. However, few studies have sought to evaluate the importance of these environments as abiotic drivers in the diversification of plant species. Of particular interest is the Late Tertiary radiation of Pachycladon, an endemic New Zealand genus of alpine cress. Here we report observations on genome-wide levels of differential expression measured in the habitats of two closely related species of Pachycladon with distinct altitudinal preferences. Using Arabidopsis microarrays, we have identified 310 predominantly hormone- and stress-response genes up-regulated in Pachycladon fastigiata and 324 genes up-regulated in Pachycladon enysii. Expression patterns for glucosinolate biosynthesis and hydrolysis genes (MAM1, MAM-I, MAM-D, AOP2, ESP, ESM1) as well as flavonoid biosynthesis genes (F3'H, FLS, FAH1) were found to be species specific. Predicted differences in flavonoid contents were partly confirmed by high performance liquid chromatography analysis. Differences in glucosinolate profiles and glucosinolate hydrolysis products obtained by high performance liquid chromatography and gas chromatography-mass spectrometry analysis, respectively, also supported inferences from expression analyses. Five glucosinolate chemotypes were matched to known Arabidopsis ecotypes, and the potential adaptive significance of these chemotypes has been discussed. Our findings, in contrast to expectations for evolution of the New Zealand flora, suggest that biotic drivers, such as plant-herbivore interactions, are likely to be as important as abiotic drivers in the diversification of Pachycladon.

Background and Aims: Crassula hunua and C. ruamahanga have been taxonomically controversial. Here their distinctiveness is assessed so that their taxonomic and conservation status can be clarified., Methods: Populations of these two species were analysed using morphological, chromosomal and DNA sequence data., Key Results: It proved impossible to differentiate between these two species using 12 key morphological characters. Populations were found to be chromosomally variable with 11 different chromosome numbers ranging from 2n = 42 to 2n = 100. Meiotic behaviour and levels of pollen stainability were both variable. Phylogenetic analyses showed that differences exist in both nuclear and plastid DNA sequences between individual plants, sometimes from the same population., Conclusions: The results suggest that these plants are a species complex that has evolved through interspecific hybridization and polyploidy. Their high levels of chromosomal and DNA sequence variation present a problem for their conservation.

Analysis of ITS sequences provides support for a clade that includes Carmichaelia, Clianthus, Montigena, and Swainsona. We provide a node-based definition and recommend that this clade be called Carmichaelinae. Results suggest that Carmichaelinae are derived from northern hemisphere Astragalinae. The clade has extensively radiated in Australia, and two independent lineages have diversified in New Zealand. The New Zealand lineages differ in species richness. One lineage consists of 24 species placed in Carmichaelia and Clianthus, while the other corresponds to the monotypic genus Montigena. The pattern of relationships inferred from ITS sequences suggests that the New Zealand radiation was recent and possibly accompanied episodes of mountain-building and glaciation.