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New Zealand is home to 16 endemic species of Lepidium (Brassicaceae), including two species considered to have become extinct since European colonisation and an additional species shared with Australia. Previous meiotic chromosome counts suggest at least some are high polyploids. A hybrid origin has been proposed for several of them, with African and American species implicated as parents. We generated amplicon sequence data for 15 genes derived from targeted enrichment data from a selection of species endemic to New Zealand, and of African, American, and Australian origin naturalised in New Zealand. These were analysed, along with publicly available genomic data from other Lepidium species. Our results are consistent with earlier work in supporting two main groups of endemic New Zealand Lepidium, corresponding to different dominant nrDNA sequences. Our data suggest that these two groups differ in ploidy (one octoploid, the ploidy of the other uncertain). The octoploid species combine four distinguishable subgenomes and the other species may be the products of allopolyploidisation between octoploid species and a diploid species closely related to, if not, L. africanum. Previously proposed links to American Lepidium are also supported, with at least two Australasian Lepidium subgenomes related to subgenomes present in American polyploid species. The affinities of two further subgenomes present in Australasian Lepidium remain to be determined, but they may also be of American origin. One New Zealand endemic species, L. naufragorum, displays sequences broadly consistent with it being the octodecaploid product of hybridisation between octoploid and decaploid New Zealand groups. [ABSTRACT FROM AUTHOR]

In vascular plant systematics there are sometimes conflicts between phenotypic and ecotypic variation and genetic differentiation that challenge species concepts, introduce taxonomic confusion, and create nomenclatural uncertainty. Until a 2014 taxonomic revision that segregated Kunzea ericoides into 10 species, it and K. sinclairii were the only species recognised in New Zealand. A recent DNA microsatellite study failed to support any of the new species, instead revealing biogeographic variation. Here we present the results of a genotyping by sequencing study with 1,361 single nucleotide polymorphisms (SNPs), sampling 48 populations representing four Kunzea species from South Island and southern North Island. The SNP study confirms the microsatellite findings: the two widespread species, K. robusta and K. serotina, are indistinguishable and share northern and southern genotypes with other species; a single metapopulation lineage reflects a national north-to-south clinal pattern; and population differentiation is low and net migration high. A significant isolation by distance pattern was revealed with SNPs. The 2014 revision was explicitly based on the unified species concept, but the primary criterion, that each species represents a separate metapopulation lineage, was not demonstrated. Species recognition was based on morphological and ecological criteria that have proved difficult to apply. Applying the unified species concept and the primary criterion of a single metapopulation genetic lineage, we now recognise just a single New Zealand species, K. ericoides, with other species constituting taxonomic synonyms. In doing so, we distinguish a grey zone of taxonomic uncertainty that reflects incomplete lineage sorting, gene flow coupled with a lack of reproductive isolation, and only partial ecotypic and phenotypic differentiation. As demonstrated in the Kunzea revision, there is considerable phenotypic and ecotypic variation in regional populations that is likely to be of ecological and conservation importance. We suggest informal ecotypes are a better way to recognise this level of variation. [ABSTRACT FROM AUTHOR]

Eco-evolutionary priority effects, in which early arriving taxa pre-empt environmental niches and evolve to exclude or marginalise later arriving taxa, have been claimed to have influenced current vegetation communities in New Zealand. We here critically assess this claim. An examination of the entire New Zealand conifer and angiosperm flora shows that early arriving lineages do not have more species than later arriving lineages, and do not dominate regional species pools. A nationwide forest plot data set shows no influence of lineage age on tree dominance. Woody species with wide latitudinal ranges tend to be older, but plant height and biotically dispersed fruit exert a stronger influence. Range extent is not influenced by lineage age in the alpine zone. The New Zealand studies on which the original claim for eco-evolutionary priority effects is based are flawed as they sample only a small fraction of the flora and plant communities and base their conclusions on a few selected lineages. The large climatic and landscape alterations of the last 50 million years, changes in the type and number of immigrant taxa establishing, and extinction are likely to have been much more influential than arrival times in shaping the extant New Zealand flora. [ABSTRACT FROM AUTHOR]

Four shrub species, including the newly described Pachystegia hesperia Heenan & Molloy, are recognised in Pachystegia Cheeseman, a genus endemic to southern Marlborough and northern Canterbury, South Island, New Zealand. Pachystegia hesperia is distinguished by its compact and low statured growth habit, obovate to elliptic-oblong leaves with the adaxial surface reticulate with distinctive primary and secondary veins, a short peduncle and narrow capitula, smaller and fewer ray petals and fewer disc florets. It was previously known by the tagnames P. "B" or P. "Lowry". Pachystegia hesperia has a western and inland distribution comprising Lowry Peaks Range, Amuri Range, and southern parts of Inland and Seaward Kaikōura Ranges. The previously recognised P. insignis (Hook.f.) Cheeseman, P. minor (Cheeseman) Molloy and P. rufa Molloy are retained. Pachystegia insignis has the most widespread distribution and includes plants referred to the tagnames P. "A" or P. "Coast" and is naturally variable in leaf shape, capitula diameter and the presence and number of leafy bracts on the peduncle. Pachystegia minor is restricted to coastal and lowland habitats between Puhi Puhi and Waiau Toa / Clarence Rivers and includes plants from Ōhau Point (Marlborough) previously known by the tagname P. "C var. ii" or P. "Ōhau Point". It is distinguished by rhomboid to obovate leaves, narrow capitula and in having the fewest florets. Pachystegia rufa is distinguished by reddish trichomes on the leaves, stems and infloresences and has a restricted distribution in Haldon Hills, Marlborough. The widespread P. insignis hybridises with P. minor and P. rufa. Typification, distribution, habitats and conservation status are presented for each species. [ABSTRACT FROM AUTHOR]

The generic placement of the enigmatic and extinct Logania depressa from New Zealand has been uncertain due to the paucity of available plant material. This diminutive plant has only been collected once from the central North Island, New Zealand, by William Colenso on 22 February 1847. Logania depressa is dioecious and the single collection comprises only male flowers and does not include female flowers or fruit that feature generic diagnostic characters. Previously its relationship to Geniostoma has been considered and its affinities to Orianthera are unknown. Orianthera has been recently recognised as a segregate of Logania. Using leaf material from a small fragment of L. depressa held in Allan Herbarium (CHR) we recovered 9,368 bp of plastid sequence data that mapped to Mitreola yangchuensis, with Mitreola being the closest generic relative of Logania for which whole genome data was available. Available genetic data for Loganiaceae is limited to several chloroplast markers, including the rps16 intron, petD intron, and petD–petB intergenic spacer. From the novel plastid sequence data for Logania depressa, 48 bp of the rps16 intron, 45 bp of the petD intron and 49 bp of the petD–petB intergenic spacer could be recovered to compare with available Loganiaceae sequences. Phylogenetic analysis of these sequences confirmed L. depressa as the only New Zealand member of Logania sens. str., but its relationships to Australian species are unresolved. [ABSTRACT FROM AUTHOR]

Tradescantia fluminensis Vell. is an invasive species in Australia, New Zealand and South Africa. To assist biocontrol initiatives and management of the species we examine genetic variation in these countries and compare this to samples collected from its natural range in Brazil. Tradescantia fluminensis comprises two genetic groupings in New Zealand, both of which are shared with Australia and South Africa. One of these genotypes is relatively common in New Zealand and this is also shared with a Brazilian population. Populations of T. fluminensis in Australia and South Africa are genetically more variable than in New Zealand. Two other entities, T. mundula Kunth (syn. T. albiflora hort.) and T. umbraculifera Hand-Mazz. (syn. T. aff. fluminensis "Big"), new names for naturalised species in New Zealand, also comprise distinct genetic groups. These genetic data emphasise the importance of correct taxonomic identification of weed species being considered for biological control programmes. Tradescantia mundula and T. umbraculifera share a similar genome size and chromosome numbers (2n = 66, 68, 70 and 2C = 14.9 picograms), whereas T. fluminensis had lower values (2n = 56, 58; 2C = 11.7 picograms). Self-pollinations of T. fluminensis and T. umbraculifera failed to produce seed, confirming that these two taxa are self-incompatible. Tradescantia mundula is self-compatible as the majority (93%) of self-pollinations produced fruit. Tradescantia umbraculifera produced a low number of fruit and seeds per fruit when pollinated by T. mundula, but no fruit or seeds were formed when it was pollinated by T. fluminensis. Tradescantia fluminensis pollinated with T. mundula or T. umbraculifera failed to produce fruit or seeds. Self-incompatibility and failure to set seed when cross-pollinated with other species suggests the invasive T. fluminensis does not pose a threat of seedling establishment in indigenous ecosystems and vegetative spread remains the main method of reproduction and invasion. [ABSTRACT FROM AUTHOR]

These are I Melicytus drucei i Molloy & B.D.Clarkson, I M. flexuosus i Molloy & A.P.Druce, I M. orarius i Heenan, de Lange, Courtney & Molloy, I M. venosus i Courtney, Heenan, Molloy & de Lange and I M. improcerus i Heenan, Courtney & Molloy (Molloy and Druce [64]; Molloy and Clarkson [59]; Heenan et al. [16]). Limestone plants The first botanical study of the limestone flora was a checklist of species for Castle Hill Nature Reserve (Molloy [47]) followed by a description of the flora and vegetation on limestone at Motanau (Molloy [49]). Second, a close working relationship with members of the New Zealand Orchid Society, including naming new species with Ian St George ( I Drymoanthus flavus i St George & Molloy) and Dan Hatch ( I Thelymitra tholiformis i Molloy & Hatch) (Molloy and Hatch [66]; Molloy and St George [71]). This includes recognition of I Leucogenes tarahaoa i Molloy and I L. neglecta i Molloy (Molloy [54]) which was a project initiated in the mid-1970s during work at Peel Forest Park (Molloy [48], p. 43). Other species named include I Cardamine cubita i Molloy, Heenan & Smissen, I Coprosma pedicellata i Molloy, de Lange & B.D.Clarkson, I Geum cockaynei i (F.Bolle) Molloy & C.J.Webb, I Hebe pareora i Garn.-Jones & Molloy, and I Heliohebe maccaskillii i (Allan) D.A.Norton & Molloy (Garnock-Jones and Molloy [10]; Molloy and Webb [72]; Molloy et al. [63]; Norton and Molloy [75]; Heenan et al. [23]). [Extracted from the article]

The type specimen and date of publication of the basionym for each of Neomyrtus pedunculata (Hook.f.) Allan and its synonym Neomyrtus vitis-idaea (Raoul) Burret are clarified to establish that the correct nomenclature is being used. Eugenia vitis-idaea Raoul is lectotypified by a Raoul specimen in Muséum National d'Histoire Naturelle (P). This lectotype specimen is conspecific with the type specimen of Myrtus pedunculata Hook.f. The publication date for Myrtus pedunculata Hook.f. is January 1844 and that for Eugenia vitis-idaea Raoul is August 1844. Therefore, Myrtus pedunculata has priority, and the final epithet pedunculata in combination with Neomyrtus provides Neomyrtus pedunculata (Hook.f.) Allan as the correct name for the species. Eugenia vitis-idaea Raoul and Neomyrtus vitis-idaea (Raoul) Burret are treated as heterotypic synonyms of Neomyrtus pedunculata (Hook.f.) Allan. [ABSTRACT FROM AUTHOR]

Indigenous plant naming systems and systematic botanical nomenclature involve different methodologies that result in different knowledge systems. Botanical nomenclature provides a single, universal name for a plant based on its taxonomic and evolutionary relationships. Indigenous classifications allow ready identification of plants for particular communities sharing a common language and cultural milieu to which the names are specific. The two systems are independent, but they can profit from mutual comparison, and each should be respected and valued for its distinctive role. A recent proposal argues that indigenous vernacular plant names, being older than those given in colonial circumstances, should have priority over existing botanical names. This suggestion, along with the call for greater use of indigenous languages in specific epithets, is here discussed in relation to the New Zealand flora. We conclude that the proposal would require extensive, complex changes to the International Code of Nomenclature, result in nomenclatural instability, and subject indigenous names to the rules of botanical nomenclature while severing them from their local cultural contexts. We suggest the proposal undermines indigenous naming systems, threatens the integrity of indigenous languages, and would disrupt botanical nomenclature for little benefit. [ABSTRACT FROM AUTHOR]

Three naming systems have been applied to the flora of Aotearoa New Zealand, but differences in their use are poorly understood. Analyses of 45 sets of Māori and settlers' vernacular plant names and botanical names in Papers Past between 1839 and 1948 shows that Māori plant names were well-used in referring to the flora. Māori plant names (2,242,201; 82.6%) are mentioned more than settlers' names (465,155; 17.1%) or botanical nomenclature (8,193; 0.3%). Māori name usage was dominant from 1839 to 1858, declined during 1859–1868 when settlers' names were featured, and increased from 53.15% in 1869 to 90.89% in 1948. In Papers Past, 32 (71.0%) of the 45 Māori plant name(s) are mentioned most often, followed by 11 (24.5%) settlers' and two (4.5%) botanical names. Analysis of the 45 sets of names in four New Zealand science journals (1863–2020) shows the number of name mentions to be: botanical nomenclature 10,827 (54.4%), Māori 6,731 (33.8%) and settlers' 2,341 (11.8%). Botanical nomenclature (35 names) and Māori names (10 names) were the most mentioned of the 45 sets of names in the science journals. Analysis of the 45 sets of names in a Google Search undertaken in 2021 confirmed the prevalence of Māori names (92.5%) over botanical nomenclature (7.5%). The most mentioned Māori names refer to plants of economic importance such as rimu, mānuka and mataī. The overall dominance of Māori plant name mentions does not support recent contentions that botanical nomenclature has 'set aside' and 'replaced' these. Further, the low number of total mentions of botanical nomenclature in Papers Past and the science journals suggests little is to be gained from promoting the use of Māori epithets in botanical nomenclature for newly named taxa, and a strategy for the promotion of Māori plant names in the context of indigenous ecological knowledge is perhaps desirable. [ABSTRACT FROM AUTHOR]

We analysed nine microsatellite markers for 260 individuals representing Sophora tomentosa and 15 species from across the geographic range of Sophora sect. Edwardsia. The purpose of the study was to characterise the Sophora species from Pacific Ocean islands and South America and determine their relationships to the eight New Zealand species, with relationships of the extinct Rapa Nui/Easter Island S. toromiro a particular focus. Structure, PCoA and NeighborNet analyses showed S. tomentosa was distinct from species of sect. Edwardsia. Among the species of sect. Edwardsia, S. cassioides, S. howinsula, S. longicarinata, S. prostrata and S. toromiro were genetically distinct as each comprised a high proportion of membership of individuals assigned to them. The remaining species were assigned to four genetic groups, each of which had one species with a high proportion of membership and other species with lower proportions of membership. The S. chrysophylla group also included high proportions of S. macrocarpa, S. denudata and S. raivavaeensis. The S. fulvida, S. godleyi and S. molloyi genetic groups mostly included low proportions of other New Zealand species. In the PCoA, S. toromiro specimens clustered together and were placed at the margin of a large sect. Edwardsia group. Sophora toromiro comprised four specimens representing the Melbourne Botanic Gardens (Australia) genotype and two specimens in the Allan Herbarium (CHR) obtained from cultivated specimens in Valparaíso (Chile) during the early 1970s. One specimen from Valparaíso was originally identified as S. toromiro, while the other was misidentified as Sophora macnabiana (now S. cassioides). The lack of genetic variation in S. toromiro suggests they were perhaps derived from the last surviving tree on Rapa Nui / Easter Island. A cultivated plant from New Zealand known as the 'Victoria Park toromiro' had its identity confirmed as S. godleyi, which is consistent with its morphological identification. [ABSTRACT FROM AUTHOR]

Neomyrtus is a New Zealand endemic monotypic genus that has been assigned to the Myrtaceae tribe Myrteae. Previous phylogenetic studies using the five genetic markers ITS, ETS, matK, psbA-trnH, and rpl16 have placed the single species Neomyrtus pedunculata in a clade with the New Zealand endemic Lophomyrtus (subtribe Ugninae), comprising the two species L. bullata and L. obcordata. Examination of the single herbarium voucher (OTA 57310) representing the plant material from which the DNA for the five phylogenetic markers was obtained revealed that it had been misidentified as Neomyrtus pedunculata and that it actually belongs to Lophomyrtus obcordata. We conducted a reanalysis of previously published data with new sequences from Neomyrtus and also undertook an analysis of 85 kbp of plastid protein coding genes from available Myrteae plastid genomes. These new phylogenetic analyses place Neomyrtus as sister to the New Caledonian endemic genus Myrtastrum, and the two species of Lophomyrtus form a clade that is sister to the Australian endemic Lenwebbia. Neomyrtus and Lophomyrtus are not closely related within the context of the tribe. This change to the understanding of Myrteae phylogeny is discussed in terms of available morphological character data and the biogeography of the tribe. Myrtastrum is currently treated as incertae sedis at subtribal rank, but along with Neomyrtus could be considered as representing a new subtribe as our analyses suggest they are not part of any of the clades hitherto recognised as subtribes. [ABSTRACT FROM AUTHOR]

Past studies of Sophora sect. Edwardsia using traditional phylogenetic and population genetic markers have been unable to produce a resolved species phylogeny of this recent radiation of shrubs and trees. Here we examined the relationships within and between the New Zealand species of Sophora sect. Edwardsia using next-generation sequencing. We generated genome-wide SNP data with double-digest restriction site-associated DNA sequencing (ddRADseq). Sophora prostrata was resolved as sister to the remaining species in all analyses. Relationships between the remaining taxa exhibited a high level of conflict with many of the genetic clusters reflecting geography rather than species boundaries. This result contrasts with a previous study, which was able to differentiate most species using genotype data from nine microsatellite loci. Overall our ddRADseq results indicate a high level of interspecific hybridisation and introgression within the group, which blurs the taxonomic boundaries throughout the distributional ranges of most species. Hybridisation and introgression among regional metapopulations comprising closely related species may increase the adaptive potential to respond to changing local conditions, and at the same time selection acts to maintain their genetic identity in the face of ongoing gene flow. [ABSTRACT FROM AUTHOR]

Tetragonia trigyna Banks & Sol. ex Hook.f. was the accepted name for a well-known coastal species in New Zealand from when it was formally named by J. D. Hooker in 1864 until the 1990s. In 1994, a Flora of Australia volume covering Norfolk and Lord Howe Islands reduced T. trigyna to synonymy of the Australian T. implexicoma (Miq.) Hook.f.. This was followed in 1999 by the first acceptance of T. implexicoma in New Zealand botanical literature when the name was used in a checklist of plant species from Aorangi Island, Poor Knights Islands. In a departure from what is generally considered accepted taxonomic practice, no empirical evidence or discussion of characters was provided in support of either decision. Subsequently, T. implexicoma has become widely used in New Zealand. The taxonomic study of T. implexicoma and T. trigyna reported here provides empirical data from herbarium specimens and cultivated plants, and concludes both species should be recognised. Tetragonia trigyna differs from T. implexicoma by its broader leaves, shorter pedicels, shorter tepals, and fewer and shorter stamens. Images in the citizen science iNaturalist platform confirm the diagnostic characters and distribution, and recently published nrDNA ITS sequence data distinguish both species. Accordingly, T. trigyna is reinstated with a distribution of New Zealand (including Chatham, Kermadec and Three Kings islands), Norfolk Island and Lord Howe Island, and T. implexicoma is considered restricted to continental Australia and Tasmania. [ABSTRACT FROM AUTHOR]

Kunzea (kānuka) in New Zealand comprises ten endemic species following a recent taxonomic revision, several of which are abundant, widespread and ecologically important as early successional colonisers. The species are difficult to recognise in the field in many areas, some plants appear intermediate between species and it has been argued hybrids are common. Microsatellite markers are used to investigate genetic variation in these ten species. The species are only weakly supported as they are characterised by low differentiation as reported by FST and high allele migration (Nm). FST varied between 0.027 (K. robusta) and 0.084 (K. triregensis). The allopatric K. triregensis and K. salterae had the highest difference in pairwise FST at 0.155 and the sympatric K. robusta and K. serotina the lowest at 0.005. Allele pairwise net migration (Nm) varied between 1.36 (K. triregensis and K. salterae) and 45.24 (K. robusta and K. serotina). The two most widespread species, K. robusta and K. serotina, are genetically indistinguishable and share northern and southern genotypic clusters. Six species or groups of species are recognised in the Structure analysis but these too are characterised by low FST and high allele migration (Nm). Four genotypic clusters shown by Structure analysis are distributed along a north to south latitudinal gradient cutting across species boundaries and corresponding with established biogeographic regions of New Zealand. This provides the strongest pattern of genotypic variation in the study. The weak level of genetic support for the ten Kunzea species, lack of breeding barriers between them, and problems in recognising some of the species in the field, raises questions as to their validity. However, given the ecological, conservation and economic importance of Kunzea, the ten species currently circumscribed should be retained until decisions are made as to how to recognise the variation within the species complex. [ABSTRACT FROM AUTHOR]

Phylogenetic diversity analyses were used to interpret the timing and assembly of vegetation communities in temperate New Zealand. A data set comprising 1638 permanent vegetation plots provided plant-distributional data, and a plastid rbcL phylogenetic tree provided phylogenetic metrics. Mean crown age, standardized effect size of mean pairwise distance and standardized effect size of mean nearest taxon distance were analysed in relation to taxonomic groups (angiosperms, gymnosperms and pteridophytes), life form (woody angiosperms, non-woody angiosperms) and temperature and precipitation using generalized additive models. Angiosperms in South Island have a younger crown age than those in most North Island sites, and phylogenetic clustering is prevalent throughout. Angiosperms and pteridophytes from drier and cooler open-habitat communities in central and eastern South Island have younger crown ages and phylogenetic clustering compared to wetter and warmer closed-habitat communities of western South Island and North Island, with older crown ages and phylogenetic over-dispersion. Phylogenetic clustering is consistent with species-rich radiations that have diversified into newly available niches during the late Miocene to Plio-Pleistocene. Pteridophytes displayed less phylogenetic relatedness than angiosperms, reflecting their older crown ages. These findings are consistent with a view that northern New Zealand retained older lineages of subtropical origin during glaciations, whereas novel habitats in cool, dry climates in southern New Zealand facilitated more recent radiations. These results emphasize the strong legacy of history in the modern-day composition of plant communities. [ABSTRACT FROM AUTHOR]

Gingidia comprises nine species of perennial herbaceous plants from New Zealand and three species from Australia. Microsatellite markers were developed for Gingidia enysii sens. lat. and G. baxterae for genetic and systematic studies of the two species in New Zealand. From sequencing a total genomic DNA library (using Roche 454), we developed nine polymorphic microsatellite markers. We tested these markers on 142 individuals from 19 populations of G. enysii sens. lat. and 10 individuals from two populations of G. baxterae. All loci amplified in both species, and exhibited species-specific alleles. In populations of G. enysii sens. lat. and G. baxterae the observed and expected heterozygosities ranged from 0.04–0.34 and from 0.31–0.80, respectively, with alleles per locus ranging from 7 to 25. Analyses of population genetic data show G. enysii sens. lat. to be naturally variable throughout its distributional range, and the suggested taxonomic novelties within G. enysii are mostly not distinct. However, populations from Banks Peninsula (Canterbury), previously referred to as Gingidium enysii var. peninsulare, are genetically discrete, and re-examination of their morphological characters is warranted. The developed markers will be valuable for future studies of taxonomy, phylogenetics, population structure, and mating system. [ABSTRACT FROM AUTHOR]

It is argued that the greater use of te reo Māori and ta re Moriori languages for naming new taxa in the flora of Aotearoa / New Zealand supports the aspirations of Māori and Te Tiriti o Waitangi. However, using these indigenous languages in botanical nomenclature is more complex than a simplistic 'more is better', and we identify a number of issues requiring consideration. We appraise Waitangi Tribunal claim Wai 262 and Te Tiriti o Waitangi, collaboration at the interface of mātauranga Māori and research science, debate whether iwi are active collaborators or informants, and, crucially, defend the credibility and utility of te reo Māori / ta re Moriori and botanical nomenclatural systems. We conclude that (1) formal botanical nomenclature and (2) te reo and ta re vernacular plant names are independent, complementary, and mutually supportive classifications, each with different purposes and denoting two functional knowledge systems. Our recommendation when naming new taxa is to derive names from botanical Latin terminology. To provide clarity for the application of indigenous languages in naming Aotearoa / New Zealand vascular plants and bryophytes, an assessment of the rules and recommendations in the International Code of Nomenclature (ICN) is presented, including the use of geographical, personal and plant vernacular names as epithets, diacritical signs, hyphens, combinations of different languages, and epithet authorship. For those considering using te reo or ta re names for a new taxon, we present guidelines that address dialogue between scientists and iwi, key aspects of the ICN to consider, and suggestions for maintaining the scientific credibility of nomenclatural practices. A knowledge gap is identified for ethnobotanical folk taxonomy research into vernacular te reo and ta re names, and to document and promote this mātauranga we recommend Māori-led research into etymology, hierarchical structure, cultural relationships, whakapapa, and relationships to botanical names. [ABSTRACT FROM AUTHOR]

A new species, Geranium cruentum, is described from New Zealand. Geranium cruentum is distinguished from G. brevicaule by its dark green leaves, broadly elliptic to obovate primary lobes with a deep sinus between the lobes, fewer secondary lobes, conspicuous dark reddish purple-brown blotches, and prominent leaf hair bases. Geranium cruentum is known from a single ostensibly wild collection made in 1993 from the Von River valley, Southland, and despite repeated searches has not been re-collected from the wild. It may be extinct in the wild but is cultivated in several gardens. As it persists ex situ in cultivation its conservation status is assessed as Threatened, Nationally Critical, using the New Zealand Threat Classification System. [ABSTRACT FROM AUTHOR]

Lineage through time plots (LTTs) are often used to explore past patterns of lineage diversification and community assembly. However, as they are based solely on extant species their ability to accurately depict past events can be questioned. Here, simulation models based on neutral processes are used to explore immigration and extinction scenarios to assist with interpretation of LTT plots generated from molecular clock age estimates for a nearly complete set of extant New Zealand vascular plant genera. With significant genus turnover, model simulations yield smooth exponential and linear semi-log LTT plots. Abrupt changes in extinction and immigration rates imposed in the scenarios caused only slight alterations of the curves. The vast majority of New Zealand vascular plant genera derive from trans-oceanic dispersal, and LTT plots generated from divergence dates and fossil data indicate consistently high turnover. Even major geological and climatic events leave minor signatures on LTT plots. Most notably, the maximum Oligocene Marine Transgression (27–22 Ma), when at least 85% of the current landmass was inundated, isn't clearly registered. By themselves, LTT plots shed little light on the biotic effects of climatic or geomorphic change in the remote past and need to be interpreted in the light of fossil and geological data. [ABSTRACT FROM AUTHOR]

The New Zealand endemic and presumed extinct Stellaria elatinoides Hook.f. is shown to be conspecific with the Australian Stellaria multiflora Hook. subsp. multiflora and is treated as a heterotypic synonym. A suite of morphological characters unifies these two taxa, including an annual growth habit, glabrous stems and leaves, sessile leaves, monochasial inflorescences, usually apetalous flowers, short styles and stamens, broadly ellipsoid capsule with valve apices strongly revolute, and the seeds suborbicular and with uniformly-sized prominent tubercles. The biostatus of Stellaria multiflora subsp. multiflora is reviewed and it is treated as indigenous to Australia and New Zealand, and since it was last collected from New Zealand in 1921 its conservation status there is confirmed as extinct. [ABSTRACT FROM AUTHOR]

A colonisation history for 411 extant genera and 477 lineages of the vascular flora of New Zealand was constructed using the plastid rbcL gene. Molecular clock crown ages suggest that the Eocene-Oligocene transition extinction at 33.9 Ma was critical to the development of the extant flora as few lineages, mostly ferns and conifers, predate this event. Based on crown dates, almost all extant angiosperm lineages have established after the Eocene-Oligocene transition extinction. The Oligocene marine transgression had little discernible impact on the formation of the extant flora, as at the culmination of the inundation (22.0–25.0 Ma) fifty extant lineages of vascular plant were present and another eight lineages originated during this time. The majority of extant species (89%) originated after the end of the Miocene Thermal Optimum at about 15.0 Ma. Nearly 50% of the extant species have evolved during mountain uplift and glaciation of the late Pliocene-Pleistocene (0–4.99 Ma). Therefore, despite a residual contribution from the Eocene, Oligocene and early to mid Miocene periods, the New Zealand vascular flora essentially originated in the late Miocene and after. [ABSTRACT FROM AUTHOR]

Brachyscome simplicifolia J.B.Armstr. was treated as incertae sedis by H.H. Allan in the Flora of New Zealand, Volume 1, published in 1961. At that time, H.H. Allan, along with the earlier flora writers T. Kirk and T.F. Cheeseman, had not seen herbarium material referable to that name. An authentic herbarium specimen from the Armstrong Herbarium, formally part of the Christchurch Botanic Gardens Herbarium (CHBG) but now housed at the Allan Herbarium (CHR), has been located and is designated as lectotype for B. simplicifolia. Based on this lectotypification, B. simplicifolia is conspecific with Abrotanella linearis Berggr., and being the more recently published name is treated as a heterotypic synonym. [ABSTRACT FROM AUTHOR]

While examining herbarium specimens of Trithuria inconspicua Cheeseman, we observed differences in the stigmatic hairs among plants from New Zealand's North and South Islands. This motivated us to assess genetic and morphological variation within this species and its sister T. filamentosa Rodway from Tasmania. Samples were collected from lakes in the three disjunct geographic areas where the two species occur. Genetic variation in both species was assessed with simple sequence-repeat (SSR, microsatellite) markers and analyses of genetic distances. We also compared the morphology of northern and southern New Zealand T. inconspicua using fresh material. Samples of each species clustered together in a minimum evolution tree built from genetic distances. Trithuria filamentosa had more genetic diversity than did T. inconspicua. Within T. inconspicua , plants from lakes in the North Island and the South Island formed discrete genetic groups diagnosable by subtle morphological differences. Low levels of heterozygosity in both species are consistent with a high level of selfing, as suggested for other co-sexual Trithuria species, but unusual for a putative apomict. On the basis of genetic and morphological variation, we propose recognition of the northern New Zealand and southern New Zealand lineages of T. inconspicua at subspecies rank. [ABSTRACT FROM AUTHOR]

Nothofagaceae (southern beech) dominate two-thirds of the remaining indigenous forest of New Zealand. Four of the five species indigenous to New Zealand belong to the genus Fuscospora, and the remaining species to Lophozonia. Two species, Fuscospora cliffortioides (mountain beech) and Fuscospora solandri (black beech), are characterised by their small, entire leaves, characters not found in other species of the genus. Their taxonomic status and rank have been a persistent problem. While individuals of each species are often well differentiated by leaf shape and growth habit, intermediate plants and populations are common. They have been described as constituting a cline with morphological variation correlated with both elevation and latitude, and have been treated by many botanists as varieties of a single species. We assessed relatedness among populations of the two taxa by NeighborNet analysis and model-based inference of population structure using simple sequence repeat data. Two gene pools corresponding to the two taxa can be recognised, and these co-exist at a regional scale. The strongest correlations between environmental variables and membership of modelled populations corresponding broadly with mountain and black beech were with mean annual temperature, elevation, and longitude. Although past (and presumably ongoing) gene flow between them has occurred in areas of contact, the hybrid zone appears to be narrow, at least in some areas. It is appropriate to recognise these recently diverged taxa at species rank, despite local gene flow. [ABSTRACT FROM AUTHOR]

Four shrub species, including three newly described, are recognised in theMelicytus obovatuscomplex from central New Zealand. The new species segregated fromM. obovatussens. str. areM. improcerus,M. orariusandM. venosus, and are recognised based on a morphological assessment of growth habit, leaf and floral characters following detailed herbarium, cultivation and field studies.Melicytus obovatusis recircumscribed to include dioecious shrubs with leaves that are usually elliptic-oblong and the petals have a prominent purple margin. It occurs on a range of calcareous substrates in northwest Nelson, from near sea level to 944 m elevation.Melicytus improcerusalso occurs in northwest Nelson and is restricted to upper montane and subalpine zones between 800 and 1500 m elevation, predominantly on marble substrates. It has a low growing, compact growth habit, is dioecious, usually has leaves that are broadly elliptic-oblong, broadly elliptic or elliptic-oblong, and petals without a prominent purple margin.Melicytus orariusis a hermaphrodite shrub with obovate, broadly obovate or narrowly obovate leaves that have a distinctly retuse apex and the petals have a prominent purple margin. It is confined to coastal habitats in Cook Strait, and in the North Island is restricted to the Wellington region where it occurs from Kapiti Island in the west to the Wairarapa coast in the east, and in the South Island it occurs throughout the Marlborough Sounds.Melicytus venosusis only known to have female flowers and may be apomictic, and has broadly elliptic, broadly elliptic-oblong or ovate-orbicular leaves that have up to six teeth mostly in the distal half of the leaf margin. Its distribution is centred on the western Marlborough Sounds, with a disjunct population known from Kapiti Island. For each species, typification, description, distribution, habitats and illustrations are presented, along with an assessment of their conservation status. [ABSTRACT FROM AUTHOR]

Forty-four rhizobial isolates from New Zealand endemicSophoraspecies growing in natural conditions were characterised and the effectiveness of selected isolates with regard to growth and N2fixation of differentSophoraspecies was tested. Sequences for the housekeeping genes (concatenatedrecA,gln11andrpoB) of the isolates were diverse but sequences for their symbiosis genes (nifHandnodC) were similar. Generally, isolates from the same field site showed similar housekeeping gene sequences. All isolates wereMesorhizobium. Twenty-six of the isolates aligned withMesorhizobiumspecies previously isolated from New Zealand nativeSophoraon the basis of their housekeeping gene sequences, but 18 isolates separated into two groups and a pair of isolates clearly separated from allMesorhizobiumtype strains. DNA–DNA hybridisations indicated that isolates in the two groups could belong to two novelMesorhizobiumspecies. Rhizobial isolates with different housekeeping gene sequences (but similar symbiosis gene sequences) gave similar increases in dry weight and total N content of fourSophoraspecies under glasshouse conditions. [ABSTRACT FROM PUBLISHER]

We examined the phylogenetic relationships withinSophorasect.Edwardsiausing DNA sequences from the chloroplasttrnQ-5′rps16andtrnHGUG-psbAintergenic spacers and the nuclear-encoded chloroplast-expressed glutamine synthetase gene. Sequences were analysed with median-joining networks and phylogenetic approaches. Low sequence diversity was detected, which is consistent with past genetic studies of the section. Chloroplast and nuclear sequences are shared across large geographic distances. The New Zealand species did not form a monophyletic group, nor did the species from Chile. However, species on some Pacific Islands (Lord Howe Island, Easter Island, Hawaii and French Polynesia) and Réunion Island in the Indian Ocean appear to have unique chloroplast haplotypes, indicating isolation. TheS. chrysophyllachloroplast haplotype derives from the French Polynesian haplotype rather thanS. denudatafrom Réunion Island, with which it shares morphological characters. In the nuclear phylogenySophora macrocarpawas sister to the remaining species that were sequenced in the section, a relationship that has been previously suggested from morphological analysis. [ABSTRACT FROM PUBLISHER]

We examined the origins ofSophoraseeds collected from the beaches of the Kermadec and Chatham Islands using chloroplast DNA sequencing and comparison with published sequences of known provenance.Sophoradoes not grow on the Kermadec Islands but two species grow on the Chatham Islands, both in low numbers. All seeds sequenced were confirmed to be fromSophorasect.Edwardsia. Several seeds exhibited novel DNA sequences that had not been found in past sampling. The remaining haplotypes have all been previously detected in the North and/or South Islands and some have also been recorded from Chile, Gough Island or the Juan Fernandez Islands. The two haplotypes that had been sequenced in the resident Chatham IslandsS. chathamicapopulation were both found in the beach-cast seeds from the islands. However, an additional four haplotypes were also detected in the Chatham Islands beach-cast seeds, indicating dispersal from elsewhere. [ABSTRACT FROM PUBLISHER]

Categorical analysis of neo- and palaeo-endemism (CANAPE), phylogenetic diversity (PD) and phylogenetic weighted endemism (PWE) were used to explore patterns of diversity, endemism and biogeography in the indigenous vascular flora of the New Zealand archipelago. Distributional data comprising 213 142 records for 436 genera and 2187 species and a phylogeny based mainly on rbcL sequences were used to calculate neo- and palaeo-endemism biodiversity metrics for 0.12° grid cells. Genus- and species-level analyses of PD revealed few significantly high-value cells mostly scattered in the northern North Island, and, for PWE, significantly high-value cells were concentrated in the northern North Island and northern offshore islands. CANAPE analyses suggested that palaeo-endemism is concentrated in northern North Island and the northern offshore islands, whereas neo-endemism is concentrated in South Island and the southern offshore islands. The areas of endemism highlighted by our analyses are compared with earlier biogeographic studies of endemism in the New Zealand flora. Some revision of previously suggested biogeographic boundaries is proposed, with the boundaries of the central South Island alpine gap being further north than previous studies have inferred, and the possibility that Pliocene marine transgression contributed to shaping the central North Island palaeo-endemism boundary is discussed. [ABSTRACT FROM AUTHOR]

The present study aimed to detect and quantify centres of vascular plant species and genus endemism and genus phylogenetic endemism in the New Zealand archipelago and to assess the representation of these in the conservation estate. The presence of 2187 vascular plant species, comprising 213 141 georeferenced records, was mapped onto 0.12° grid cells and a genus-level phylogeny was constructed mainly from rbcLsequences used to calculate phylogenetic metrics. Previously identified centres of endemism were confirmed, and new areas of endemism were suggested. Patterns of endemism differ with taxonomic rank. Randomisations showed that the South Island mountains have greater species corrected weighted endemism (CWE) than expected, whereas the randomisations for genus CWE and genus corrected phylogenetic endemism (CPE) showed the northern half of the North Island and northern offshore islands to have greater endemism than expected. Consistent with the randomisations, the highest values of genus CWE and genus CPE predominantly occur in the northern North Island and offshore islands. Centres of species CWE, genus CWE and genus CPE, supported by randomisation analyses, overlap with the New Zealand conservation estate by 40.01, 29.52 and 19.12% respectively. Many areas of high endemism are often poorly protected, highlighting the urgency to consider the areas of endemism identified here in conservation policy, planning and management. [ABSTRACT FROM AUTHOR]

Aim To date, there have been few studies investigating the phylogeography of forest trees that are widely distributed in New Zealand. Our main objective was to examine the phylogeographic distribution of chloroplast DNA from New Zealand Sophora trees with respect to known biogeographical regions, proposed refugia and species boundaries. A second objective was to investigate the origins of the southern and Chatham Island populations of Sophora chathamica, which have been proposed to derive from Māori translocation. Location The New Zealand archipelago coastal and lowland forests. Methods We sequenced the chloroplast trnQ5′-rps16 intergenic spacer from 416 samples of Sophora, representing all of the New Zealand species. A median-joining network was used to analyse haplotype relationships. Phylogeographic structuring was assessed with GST and NST calculations and spatial analysis of molecular variance ( SAMOVA). Analyses of molecular variance were used to test partitioning schemes including species divisions and proposed biogeographical boundaries. Results A total of 22 haplotypes were recovered. Moderate genetic differentiation was detected and it had a phylogeographic component but no higher level groupings were found with a SAMOVA. Very little of the chloroplast variation was partitioned by species boundaries or geography. Haplotype diversity decreased from north to south but was not higher in proposed major lowland forest glacial refugia. Populations of Sophora chathamica suggested to derive from Māori translocations contained a haplotype not detected from the proposed natural range of the species. Main conclusions Sophora survived the Last Glacial Maximum in widespread populations throughout much of the country, although our data did not provide evidence for survival in the southern South Island. Chloroplast sharing among New Zealand Sophora species likely results from hybridization and introgression. Our results indicate that the occurrence of S. chathamica in the southern North Island, northern South Island and Chatham Islands is likely to be natural, although the planting by Māori of some of the individuals in the southern North Island and Chatham Islands cannot be excluded. [ABSTRACT FROM AUTHOR]

The ecological conditions promoting evolutionary priority effects, where the order and timing of ancestral species arrival into a new habitat influences extant community assembly, are poorly understood. Studies in the New Zealand alpine indicated that early-arriving angiosperm lineages dominated communities via niche pre-emption. Forests have a much longer (>60 myr) evolutionary history in New Zealand than alpine communities (<2 myr) and greater structural complexity., Here we ask whether community effects of arrival order persist in cool temperate forest communities in southern New Zealand that have assembled throughout the Cenozoic. Combining phylogenetically derived clade ages and forest vegetation data from across a mountain range, we compare effects of clade age on relative richness and abundance of two taxonomic groups (pteridophytes and angiosperms) along precipitation gradients., We show that older clades of both groups tended to have greater relative abundance and older angiosperm clades had greater relative richness. Relative richness and abundance also increased with regional clade diversity, independent of clade age., The strength of the clade age effect on community dominance changed differently along precipitation gradients depending on the response and taxonomic group. Clade age had a stronger effect on relative abundance of pteridophytes with increasing elevation and westerliness (i.e. as precipitation increased). In contrast, the effect of clade age on relative abundance of angiosperms decreased with westerliness. Precipitation did not alter the clade age effect on relative richness., Synthesis. We show that evolutionary priority effects persist in communities with a longer evolutionary history than has been investigated to date and across physiologically contrasting taxonomic groups, suggesting priority effects are general drivers of community assembly over macro-evolutionary time-scales. Furthermore, the strength of evolutionary priority effects attenuated along a gradient of decreasing resources, at least for pteridophytes, which improves our ability to predict conditions in which the arrival order of lineages influences community assembly. [ABSTRACT FROM AUTHOR]

L epidium castellanum, L . juvencum and L . oleraceum are threatened coastal cresses endemic to New Zealand. These three species were selfed and interspecific hybrids generated for examination of hybrid fitness and inbreeding depression. In controlled glasshouse experiments, the interspecific hybrids and selfed progeny were inoculated with a strain of the introduced Turnip mosaic virus ( TuMV) previously isolated from wild populations of L . aegrum. Experiments tested the hypothesis that heterosis in the interspecific hybrids provides a gain in TuMV resistance in comparison to selfed plants. We show that interspecific hybrids of three genetically distinct species of L epidium increased plant performance and reduced susceptibility to the effects of the TuMV. We suggest that interspecific hybridization could be implemented as a conservation management strategy and that a broader outlook may be required to mitigate the negative impacts of introduced pathogens on threatened species. [ABSTRACT FROM AUTHOR]

Plant radiations are widespread but their influence on community assembly has rarely been investigated. Theory and some evidence suggest that radiations can allow lineages to monopolize niche space when founding species arrive early into new bioclimatic regions and exploit ecological opportunities. These early radiations may subsequently reduce niche availability and dampen diversification of later arrivals., We tested this hypothesis of time-dependent lineage diversification and community dominance using the alpine flora of New Zealand. We estimated ages of 16 genera from published phylogenies and determined their relative occurrence across climatic and physical gradients in the alpine zone. We used these data to reconstruct occupancy of environmental space through time, integrating palaeoclimatic and palaeogeological changes., Our analysis suggested that earlier-colonizing lineages encountered a greater availability of environmental space, which promoted greater species diversity and occupancy of niche space. Genera that occupied broader niches were subsequently more dominant in local communities. An earlier time of arrival also contributed to greater diversity independently of its influence in accessing niche space., We suggest that plant radiations influence community assembly when they arise early in the occupancy of environmental space, allowing them to exclude later-arriving colonists from ecological communities by niche preemption. [ABSTRACT FROM AUTHOR]

Aim Priority effects, in which the order and timing of species arrival influence community assembly, are thought to be stronger in less stressful environments, reflecting increased competition, but this hypothesis has rarely been examined over evolutionary time. Here, we test the hypothesis using an island community of alpine plants. Location Murchison Mountains, South Island, New Zealand. Methods Lineage age data for 14 monophyletic New Zealand alpine plant genera, with stem ages ranging from 2 to 17 Ma, were paired with species presence and abundance data in 261 plots, covering nearly 400 km2. The relationships between lineage age and the relative abundance and richness of focal genera across elevation (800-1620 m) and precipitation (2500-5000 mm yr−1) gradients were investigated using linear models in a Bayesian framework. Results The relative abundance of focal genera increased with lineage age, but this effect was weaker at higher elevation and precipitation, where plants are likely to have experienced more stressful conditions. The relative richness of focal genera increased at a consistent rate despite significant changes in overall richness of focal genera across both elevation and precipitation gradients. Main conclusions Our results suggest that priority effects, on a time-scale of millions of years and involving significant evolutionary change, influence community assembly, leading to increased dominance of older lineages, but that the strength of these effects may vary with environmental conditions. Environmental gradients correlated with abiotic stress, such as elevation in alpine systems, may be particularly important for predicting the strength of both ecological and evolutionary priority effects. [ABSTRACT FROM AUTHOR]

Adaptive radiations such as the Darwin finches in the Galapagos or the cichlid fishes from the Eastern African Great Lakes have been a constant source of inspiration for biologists and a stimulus for evolutionary thinking. A central concept behind adaptive radiation is that of evolution by niche shifts, or ecological speciation. Evidence for adaptive radiations generally requires a strong correlation between phenotypic traits and the environment. But adaptive traits are often cryptic, hence making this phenotype-environment approach difficult to implement. Here we propose a procedure for detecting adaptive radiation that focuses on species' ecological niche comparisons. It evaluates whether past ecological disparity in a group fits better a neutral Brownian motion model of ecological divergence or a niche shift model. We have evaluated this approach on New Zealand rockcresses (Pachycladon) that recently radiated in the New Zealand Alps. We show that the pattern of ecological divergence rejects the neutral model and is consistent with that of a niche shift model. Our approach to detect adaptive radiation has the advantage over alternative approaches that it focuses on ecological niches, a key concept behind adaptive radiation. It also provides a way to evaluate the importance of ecological speciation in adaptive radiations and will have general application in evolutionary studies. In the case of Pachycladon, the high estimated diversification rate, the distinctive ecological niches of species, and the evidence for ecological speciation suggest a remarkable example of adaptive radiation. [ABSTRACT FROM AUTHOR]

Predicting survival and extinction scenarios for climate change requires an understanding of the present day ecological characteristics of species and future available habitats, but also the adaptive potential of species to cope with environmental change. Hybridization is one mechanism that could facilitate this. Here we report statistical evidence that the transfer of genetic information through hybridization is a feature of species from the plant genus Pachycladon that survived the Last Glacial Maximum in geographically separated alpine refugia in New Zealand's South Island. We show that transferred glucosinolate hydrolysis genes also exhibit evidence of intra-locus recombination. Such gene exchange and recombination has the potential to alter the chemical defence in the offspring of hybridizing species. We use a mathematical model to show that when hybridization increases the adaptive potential of species, future biodiversity will be best protected by preserving closely related species that hybridize rather than by conserving distantly related species that are genetically isolated. [ABSTRACT FROM AUTHOR]

Three new species of Gingidia (Apiaceae: Apioideae) segregated from the G. montana (J.R.Forst. & G.Forst.) J.W.Dawson complex are named, with G. montana now regarded as a New Zealand endemic. The new Australian endemic, G. rupicola I.Telford & J.J.Bruhl, is restricted to the eastern escarpment of the New England Tableland, New South Wales. With few populations and limited numbers of plants, the conservation assessment of G. rupicola is Endangered. G. haematitica Heenan is described as a new species from North-West Nelson, South Island, New Zealand, where it is restricted to base-rich substrates in the Burnett Range. Because of its restricted distribution and the continued mining for dolomite at the site of the largest population, G. haematitica is considered to have a conservation assessment of Nationally Critical. The second New Zealand endemic, G. amphistoma Heenan, is known from alpine habitats in the Southern Alps, South Island. Distributions of the three new species are mapped, habitats noted, and a table compares attributes of these species and G. montana. [ABSTRACT FROM AUTHOR]

New Zealand became geographically isolated about 80 million years ago and this separation gave rise to a unique native flora including four genera of legume, Carmichaelia, Clianthus and Montigena in the Carmichaelinae clade, tribe Galegeae, and Sophora, tribe Sophoreae, sub-family Papilionoideae. Ten bacterial strains isolated from NZ Carmichaelinae growing in natural ecosystems grouped close to the Mesorhizobium huakuii type strain in relation to their 16S rRNA and nifH gene sequences. However, the ten strains separated into four groups on the basis of their recA and glnII sequences: all groups were clearly distinct from all Mesorhizobium type strains. The ten strains separated into two groups on the basis of their nodA sequences but grouped closely together in relation to nodC sequences; all nodA and nodC sequences were novel. Seven strains selected and the M. huakuii type strain (isolated from Astragalus sinicus) produced functional nodules on Carmichaelia spp., Clianthus puniceus and A. sinicus but did not nodulate two Sophora species. We conclude that rhizobia closely related to M. huakuii on the basis of 16S rRNA and nifH gene sequences, but with variable recA and glnII genes and novel nodA and nodC genes, are common symbionts of NZ Carmichaelinae. [ABSTRACT FROM AUTHOR]

Sequence data from the internal transcribed spacer (ITS) nrDNA and rbcL cpDNA regions were used to determine relationships of genera of Brassicaceae from Australia and New Zealand (NZ) that were previously unassigned to a tribe. Maxi-mum likelihood analysis of 71 ITS sequences identified a monophyletic clade of Australian genera, including Carinavalva and Microlepidium that had previously been assigned to the tribe Microlepidieae. Pachycladon is not supported as monophyletic, comprising a clade of the NZ species and another clade of the Tasmanian P. radicatum. These two Pachycladon clades form a polytomy with the Australian clade. Maximum likelihood analysis of the rbcL region generally supports the ITS analysis with the Australian genera forming a monophyletic clade with Pachycladon. Arabidella is polyphyletic in the rbcL phylogeny as A. eremigena is member of the Australian clade but A. trisecta is placed in a sister clade that comprises mainly genera of tribe Camelineae. As a result of these phylogenetic analyses the tribe Microlepidieae is expanded and now includes 16 genera and 56 species endemic to Australia and New Zealand. Genera included in the Microlepidieae axe Arabidella, Ballantinia, Blen-nodia, Carinavalva, Cuphonotus, Drabastrum, Geococcus, Harmsiodoxa, Irenepharsus, Menkea, Microlepidium, Pachycladon, Pachymitus, Phlegmatospermum, Scambopus and Stenopetalum. Whole-genome duplication has previously been shown to have occurred in the ancestry of Arabidella, Ballantinia, Pachycladon and Stenopetalum and is likely to be a defining feature of the tribe Microlepidieae. Future research needs to investigate circumscription of the Australian genera as there is a predominance of closely related monotypic genera in the Microlepidieae. With resolution of the tribal placement of these Australian and New Zealand genera, ca. 94% (302) of the 321 genera in the family have been assigned to a tribe. [ABSTRACT FROM AUTHOR]

Austroderia turbaria Connor is a threatened grass endemic to the Chatham Islands. Although formerly more widespread, remaining natural populations consist of highly fragmented remnants and/or individuals. Population genetic analysis of seed-raised progeny from six of the extant natural populations on Chatham and Pitt islands, using amplified fragment length polymorphisms (AFLPs) and microsatellite markers, shows that there are very low levels of variation (expected estimated heterozygosity He 0.023-0.030, no. of effective alleles Na 1.039-1.053), and no significant differentiation within or between populations on the two islands. Flow cytometric analysis of endosperm to embryo ratios suggests a sexual breeding system. This lack of population variation and no discernable differences between the two islands suggest that management practices such as the establishment of new populations can be carried out irrespective of the location of source material. One caveat to this is the possibility of Fusarium wilt occurring on the islands, in which case measures should be taken to best prevent spread across the range of the species. [ABSTRACT FROM AUTHOR]

Background: Pachycladon (Brassicaceae, tribe Camelineae) is a monophyletic genus of ten morphologically and ecogeographically differentiated, and presumably allopolyploid species occurring in the South Island of New Zealand and in Tasmania. All Pachycladon species possess ten chromosome pairs (2n = 20). The feasibility of comparative chromosome painting (CCP) in crucifer species allows the origin and genome evolution in this genus to be elucidated. We focus on the origin and genome evolution of Pachycladon as well as on its genomic relationship to other crucifer species, particularly to the allopolyploid Australian Camelineae taxa. As species radiation on islands is usually characterized by chromosomal stasis, i.e. uniformity of chromosome numbers/ploidy levels, the role of major karyotypic reshuffling during the island adaptive and species radiation in Pachycladon is investigated through whole-genome CCP analysis. Results: The four analyzed Pachycladon species possess an identical karyotype structure. The consensual ancestral karyotype is most likely common to all Pachycladon species and corroborates the monophyletic origin of the genus evidenced by previous phylogenetic analyses. The ancestral Pachycladon karyotype (n = 10) originated through an allopolyploidization event between two genomes structurally resembling the Ancestral Crucifer Karyotype (ACK, n = 8). The primary allopolyploid (apparently with n = 16) has undergone genome reshuffling by descending dysploidy toward n = 10. Chromosome "fusions" were mediated by inversions, translocations and centromere inactivation/loss. Pachycladon chromosome 3 (PC3) resulted from insertional fusion, described in grasses. The allopolyploid ancestor originated in Australia, from the same or closely related ACK-like parental species as the Australian Camelineae allopolyploids. However, the two whole-genome duplication (WGD) events were independent, with the Pachycladon WGD being significantly younger. The long-distance dispersal of the diploidized Pachycladon ancestor to New Zealand was followed by the Pleistocene species radiation in alpine habitats and characterized by karyotypic stasis. Conclusions: Karyotypic stasis in Pachycladon suggests that the insular species radiation in this genus proceeded through homoploid divergence rather than through species-specific gross chromosomal repatterning. The ancestral Pachycladon genome originated in Australia through an allopolyploidization event involving two closely related parental genomes, and spread to New Zealand by a long-distance dispersal. We argue that the chromosome number decrease mediated by inter-genomic reshuffling (diploidization) could provide the Pachycladon allopolyploid founder with an adaptive advantage to colonize montane/alpine habitats. The ancestral Pachycladon karyotype remained stable during the Pleistocene adaptive radiation into ten different species. [ABSTRACT FROM AUTHOR]

Background: Transcript profiling of closely related species provides a means for identifying genes potentially important in species diversification. However, the predictive value of transcript profiling for inferring downstreamphysiological processes has been unclear. In the present study we use shotgun proteomics to validate inferences from microarray studies regarding physiological differences in three Pachycladon species. We compare transcript and protein profiling and evaluate their predictive value for inferring glucosinolate chemotypes characteristic of these species. Results: Evidence from heterologous microarrays and shotgun proteomics revealed differential expression of genes involved in glucosinolate hydrolysis (myrosinase-associated proteins) and biosynthesis (methylthioalkylmalate isomerase and dehydrogenase), the interconversion of carbon dioxide and bicarbonate (carbonic anhydrases), water use efficiency (ascorbate peroxidase, 2 cys peroxiredoxin, 20 kDa chloroplastic chaperonin, mitochondrial succinyl CoA ligase) and others (glutathione-S-transferase, serine racemase, vegetative storage proteins, genes related to translation and photosynthesis). Differences in glucosinolate hydrolysis products were directly confirmed. Overall, prediction of protein abundances from transcript profiles was stronger than prediction of transcript abundance from protein profiles. Protein profiles also proved to be more accurate predictors of glucosinolate profiles than transcript profiles. The similarity of species profiles for both transcripts and proteins reflected previously inferred phylogenetic relationships while glucosinolate chemotypes did not. Conclusions: We have used transcript and protein profiling to predict physiological processes that evolved differently during diversification of three Pachycladon species. This approach has also identified candidate genes potentially important in adaptation, which are now the focus of ongoing study. Our results indicate that protein profiling provides a valuable tool for validating transcript profiles in studies of adaptive divergence. [ABSTRACT FROM AUTHOR]

An artificial intergeneric hybrid derived from sexual hybridization between Arabidopsis thaliana (female) and Pachycladon cheesemanii (male) is characterized and formally named as × Pachydopsis hortorum. A hybrid origin for × Pachydopsis is supported by a chromosome number of 2 n = 15, with this comprising haploid gametes from A. thaliana ( n = 5) and P. cheesemanii ( n = 10). DNA fingerprinting using amplified fragment length polymorphism data also confirmed the parentage of the hybrid, as it comprised the additive total of all of the fragments scored for P. cheesemanii and most of those scored for A. thaliana. × Pachydopsis is a robust perennial herb with numerous leafy rosettes and long inflorescences like P. cheesemanii, and floral parts that are intermediate between the parents. × Pachydopsis produces sterile pollen. Female function of × Pachydopsis is partially normal, with the pollen of A. thaliana and several species of Pachycladon readily germinating on the stigma, and pollen tubes growing down the style and transmission tissue into the ovary. No seed was formed from these pollinations, although one embryo developed but subsequently aborted at the torpedo stage. Colchicine was used to induce polyploid inflorescences, and these were confirmed by the size and density of the stomata and pollen diameter. Flowers from the polyploid inflorescences of × Pachydopsis were backcrossed with A. thaliana Landsberg erecta and 11 seeds were produced. Four backcross hybrid plants were raised and two of these had a chromosome number of 2 n = 20, consistent with a haploid gamete ( n = 15) from polyploid × Pachydopsis being fertilized by a haploid pollen gamete ( n = 5) from A. thaliana Landsberg erecta. Polyploid × Pachydopsis flowers backcrossed with P. cheesemanii and crossed with P. novae-zelandiae did not produce any seeds. The partially fertile intergeneric hybrid described here between Arabidopsis and Pachycladon is remarkable in that, although the two genera occur in an Arabidopsoid clade, they are separated by a reasonable phylogenetic distance. This relationship suggests that Pachycladon and × Pachydopsis have the potential to be employed in the study of evolutionary and ecological processes using the wide array of Arabidopsis resources. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157, 533–544. [ABSTRACT FROM AUTHOR]

SummaryAim The aim is to use DNA sequence data to test between vicariance and long range dispersal (by floating seed-pods) explanations for the origin and range of the Edwardsia species of Sophora (Sophoreae: Papilionoideae: Leguminosae). Location This group is widely distributed around the South Pacific and into the South Atlantic on both continental fragments and oceanic islands. Methods DNA sequences from an intergene region (atpB-rbcL) of the chloroplast were determined for twelve taxa (including outgroups) and used to test these hypotheses. Sophora fossils were used to calibrate the evolutionary tree. Results The Edwardsia group of Sophora appears monophyletic and is well differentiated from other Sophora. However, the genetic difference between species within the South Pacific and to the South Atlantic is very low. Main conclusionsThe results eliminate vicariance explanations for this section of Sophora and strongly support an origin from other (non-Edwardsia) Sophora in the north-west Pacific. Dispersal appears initially to be to Tuvalu, Lord Howe Island, New Zealand, and subsequently across the South Pacific, probably within the last 2–5 million years. Dispersal of buoyant Sophora seeds to oceanic islands is the most likely explanation of its distributions. Fossil pollen dates in New Zealand are consistent with the conclusion. [ABSTRACT FROM AUTHOR]