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The taxonomy of several species of Goodenia with connate bracts allied to G. panduriformis (A.Cunn. ex Benth.) K.A.Sheph. was evaluated through morphological assessment of herbarium specimens. Consequently, the circumscriptions of G. connata (F.Muell.) K.A.Sheph., G. discophora (F.Muell.) K.A.Sheph., G. daviesii (F.Muell.) K.A.Sheph. and G. panduriformis are revised and new descriptions provided. Three new species, G. aluta K.A.Sheph. & Lepschi, G. crescentiloba K.A.Sheph. & Lepschi and G. obscurata K.A.Sheph. & Lepschi are also recognised, the latter being listed as a species of conservation concern. Further, a replacement lectotype for Velleia helmsii K.Krause is designated and a key, distribution maps and figures are included. [ABSTRACT FROM AUTHOR]

Close scrutiny of Goodenia (Goodeniaceae) and allied genera in the 'Core Goodeniaceae' over recent years has clarified our understanding of this captivating group. While expanded sampling, sequencing of multiple regions, and a genome skimming reinforced backbone clearly supported Goodenia s.l. as monophyletic and distinct from Scaevola and Coopernookia, there appears to be no synapomorphic characters that uniquely characterise this morphologically diverse clade. Within Goodenia s.l., there is strong support from nuclear, chloroplast and mitochondrial data for three major clades (Goodenia Clades A, B and C) and various subclades, which lead to earlier suggestions for the possible recognition of these as distinct genera. Through ongoing work, it has become evident that this is impractical, as conflict remains within the most recently diverged Clade C, likely due to recent radiation and incomplete lineage sorting. In light of this, it is proposed that a combination of morphological characters is used to circumscribe an expanded Goodenia that now includes Velleia, Verreauxia, Selliera and Pentaptilon, and an updated infrageneric classification is proposed to accommodate monophyletic subclades. A total of twenty-five new combinations, three reinstatements, and seven new names are published herein including Goodenia subg. Monochila sect. Monochila subsect. Infracta K.A.Sheph. subsect. nov. Also, a type is designated for Goodenia subg. Porphyranthus sect. Ebracteolatae (K.Krause) K.A.Sheph. comb. et stat. nov., and lectotypes or secondstep lectotypes are designated for a further three names. [ABSTRACT FROM AUTHOR]

Camel melon (Citrullus lanatus), colocynth (Citrullus colocynthis) and prickly paddy melon (Cucumis myriocarpus) are summer-growing invasive weeds distributed throughout Australia. We used DNA-sequence information from samples collected across Australia and morphological data from glasshouse-grown plants to determine diagnostic features of these species, and to determine the infraspecific identity of Australian Citrullus lanatus and Cucumis myriocarpus. All species possessed distinct genotypes and haplotypes at nuclear G3pdh and chloroplast ycf6-psbM gene regions and could be easily identified on the basis of molecular phylogenetic analysis. A combination of vegetative, floral, fruit and seed characters also allowed for species identification at all developmental stages. On the basis of our morphological and molecular analyses, Australian camel melon and prickly paddy melon populations were identified as Citrullus lanatus var. citroides and Cucumis myriocarpus subsp. myriocarpus respectively. [ABSTRACT FROM AUTHOR]

Olearia heloderma Albr. & I.Telford, sp. nov., a distinctive species from the mountainous region near the Australian Capital Territory and New South Wales border is described and illustrated, with notes on distribution, habitat, conservation status, relationships and features distinguishing it from other species of Olearia. [ABSTRACT FROM AUTHOR]

It is argued that the inclusion of spatially heterogeneous environments in biodiversity reserves will be an effective means of encouraging ecosystem resilience and plant community conservation under climate change. However, the resilience and resistance of plant populations to global change, the specific life-history traits involved and the spatial scale at which environmentally driven demographic variation is expressed remains largely unknown for most plant groups. Here we address these questions by reporting an empirical investigation into the impacts of an unprecedented 3-year drought on the demography, population growth rates ( λ) and biogeographical distribution of core populations of the perennial grassland species Austrostipa aristiglumis in semiarid Australia. We use life-history analysis and periodic matrix population models to specifically test the hypothesis that patch- and habitat-scale variation in vital life-history parameters result in spatial differences in the resilience and resistance of A. aristiglumis populations to extreme drought. We show that the development of critical soil water deficits during drought resulted in collapse of adult A. aristiglumis populations ( λ≪1), rapid interhabitat phytosociological change and overall contraction towards mesic refugia where populations were both more resistant and resilient to perturbation. Population models, combined with climatic niche analysis, suggest that, even in core areas, a significant reduction in size and habitat range of A. aristiglumis populations is likely under climate change expected this century. Remarkably, however, we show that even minor topographic variation (0.2-3 m) can generate significant variation in demographic parameters that confer population-level resilience and resistance to drought. Our findings support the hypothesis that extreme climatic events have the capacity to induce rapid, landscape-level shifts in core plant populations, but that the protection of topographically heterogeneous environments, even at small spatial scales, may play a key role in conserving biodiversity under climate change in the coming century. [ABSTRACT FROM AUTHOR]

Ecologists have long sought to understand why some species are rare and others common. For the most part, inconsistent relationships between local rarity and underlying mechanisms have emerged. One possibility for this inconsistency is that locally rare species may not always be rare. However, it is largely unknown whether most locally rare species in a community possess the capacity to become abundant elsewhere in their geographical range. Here, we identified 57 locally rare plant species of open forest in south-eastern Australia. We found that most of these species (91%) occurred in higher abundance at other sites within their geographical range (somewhere-abundant species), while the remaining small percentage of locally rare species were consistently rare (everywhere-sparse species). Somewhere-abundant species had significantly smaller seeds on average than everywhere-sparse species in cross-species regression analysis. This pattern was not maintained when the influence of other life-history attributes was controlled for, or when phylogenetic relatedness among species was considered explicitly in phylogenetic regression analysis. In both cross-species and phylogenetic regressions, somewhere-abundant and everywhere-sparse species did not differ significantly with respect to growth form, height, regeneration-after-fire strategy, or dispersal. Our findings provide further evidence for the notion that theories to account for local rarity which are couched in terms of within-community interactions alone are incomplete for the majority of species, because they need to account for different outcomes in different places. [ABSTRACT FROM AUTHOR]

We investigated some of the factors influencing exotic invasion of native sub-alpine plant communities at a site in southeast Australia. Structure, floristic composition and invasibility of the plant communities and attributes of the invasive species were studied. To determine the plant characteristics correlated with invasiveness, we distinguished between roadside invaders, native community invaders and non-invasive exotic species, and compared these groups across a range of traits including functional group, taxonomic affinity, life history, mating system and morphology. Poa grasslands and Eucalyptus-Poa woodlands contained the largest number of exotic species, although all communities studied appeared resilient to invasion by most species. Most community invaders were broad-leaved herbs while roadside invaders contained both herbs and a range of grass species. Over the entire study area the richness and cover of native and exotic herbaceous species were positively related, but exotic herbs were more negatively related to cover of specific functional groups (e.g. trees) than native herbs. Compared with the overall pool of exotic species, those capable of invading native plant communities were disproportionately polycarpic, Asteracean and cross-pollinating. Our data support the hypothesis that strong ecological filtering of exotic species generates an exotic assemblage containing few dominant species and which functionally converges on the native assemblage. These findings contrast with those observed in the majority of invaded natural systems. We conclude that the invasion of closed sub-alpine communities must be viewed in terms of the unique attributes of the invading species, the structure and composition of the invaded communities and the strong extrinsic physical and climatic factors typical of the sub-alpine environment. [ABSTRACT FROM AUTHOR]

Circumscription of the large genus Pultenaea Sm. has been contentious since shortly after description. We draw on recently generated phylogenomic data to provide a fully resolved phylogeny of Pultenaea and related genera based on near-complete species level sampling for the genus. Phylogenomic data divide Pultenaea sens. lat. into five independent lineages, corresponding to previously identified clades, that we recognise as distinct genera. Pultenaea sens. str. contains most of the currently recognised species and as circumscribed here, all of the species are endemic to eastern Australia except for P. tenuifolia R.Br. & Sims that extends across the Nullarbor into Western Australia. The genus Euchilus R.Br. is reinstated for eight species, all endemic to south-west Western Australia except for E. elachistus (F.Muell.) R.L.Barrett & Orthia that also occurs in South Australia. Three new genera are described, with all of the constituent species endemic to south-west Western Australia: Grievea R.L.Barrett, Clugston & Orthia, with two species, Jennata R.L.Barrett, Clugston & Orthia, with nine species and Loricobbia R.L.Barrett, Clugston & Orthia with six species. Pultenaea adunca Turcz. remains unplaced but we exclude this species from our concept of Pultenaea. Twenty-one new combinations are made: Euchilus aridus (E.Pritz.) R.L.Barrett & Orthia, E. calycinus subsp. proxenus (Orthia & Chappill) Orthia & R.L.Barrett, E. daena (Orthia & Chappill) Orthia & R.L.Barrett, E. elachistus (F.Muell.) R.L.Barrett & Orthia, Grievea brachytropis (Benth. ex Lindl.) R.L.Barrett & Orthia, G. craigiana (C.F.Wilkins, Orthia & Crisp) Orthia & R.L.Barrett, Jennata brachyphylla (Turcz.) R.L.Barrett & Clugston, J. empetrifolia (Meisn.) R.L.Barrett & Clugston, J. ericifolia (Benth.) R.L.Barrett & Clugston, J. indira (Orthia & Crisp) Orthia & R.L.Barrett, J. indira subsp. monstrosita (Orthia) Orthia & R.L.Barrett, J. indira subsp. pudoides (Orthia) Orthia & R.L.Barrett, J. radiata (H.B.Will.) R.L.Barrett & Clugston, J. strobilifera (Meisn.) R.L.Barrett & Clugston, J. verruculosa (Turcz.) R.L.Barrett & Clugston, Loricobbia aspalathoides (Meisn.) R.L.Barrett & T.D.Macfarl., L. ochreata (Meisn.) R.L.Barrett & T.D.Macfarl., L. pauciflora (M.B.Scott) R.L.Barrett & T.D.Macfarl., L. pinifolia (Meisn.) R.L.Barrett & T.D.Macfarl., L. reticulata (Sm.) R.L.Barrett & T.D.Macfarl. and L. skinneri (F.Muell.) R.L.Barrett & T.D.Macfarl. The bush-pea genus (Pultenaea) is one of the larger legume genera in Australia but has been difficult to define. We present a new classification of the group, recognising five genera instead of one using a large DNA based analysis of relationships. Three genera are newly described and one genus is reinstated, and these are almost entirely restricted to south-west Western Australia, with true Pultenaea being mostly restricted to eastern Australia. (Photograph by Russell Barrett.) This article belongs to the collection Genomics for Australian Plants. [ABSTRACT FROM AUTHOR]

The article offers information about Melaleuca marginata, which is a new name for Melaleuca coronicarpa, Myrtaceae. It mentions that the type material of Melaleuca marginata is probably weak and the name specifically appropriate for the species. Moreover, it notes that the species is common in the wheatbelt regions of Western Australia

Introduced species lists provide essential background information for biological invasions research and management. The compilation of these lists is, however, prone to a variety of errors. We highlight the frequency and consequences of such errors using introduced Melaleuca (sensu lato, including Callistemon) species in South Africa as a case study. We examined 111 herbarium specimens from South Africa and noted the categories and sub-categories of errors that occurred in identification. We also used information from herbarium specimens and distribution data collected in the field to determine whether a species was introduced, naturalized and invasive. We found that 72% of the specimens were not named correctly. These were due to human error (70%) (misidentification, and improved identifications) and species identification problems (30%) (synonyms arising from inclusion of Callistemon, and unresolved taxonomy). At least 36 Melaleuca species have been introduced to South Africa, and field observations indicate that ten of these have naturalized, including five that are invasive. While most of the errors likely have negligible impact on management, we highlight one case where incorrect identification lead to an inappropriate management approach and some instances of errors in published lists. Invasive species lists need to be carefully reviewed to minimise errors, and herbarium specimens supported by DNA identification are required where identification using morphological features is particularly challenging. [ABSTRACT FROM AUTHOR]

Aims We implemented a neutral model of a positive relationship between abundance and distribution (occupancy) to examine how spatial structure influences abundance--occupancy relationships. The spatially explicit neutral model distributes individuals of species randomly and independently of one another in space to produce a positive abundance--occupancy relationship. Using empirical data, we tested whether abundance--occupancy relationships diverged significantly from the theoretical neutral model, and determined whether significant divergences emerged through intraspecific aggregation or over-dispersion of individuals. Location Field work was conducted in open-forest vegetation of the Black Mountain region in south-eastern Australia. Methods At eight floristically similar sites in open-forest vegetation, we established a 20 x 20 m census plot and spatially mapped all individuals of each woody species. The abundance and distribution of each species was determined at each site at three spatial scales within the census plot. Observed abundance--occupancy relationships were compared with the spatially explicit neutral model using linear regression techniques. Monte-Carlo methods using a two dimensional Poisson process were then used to classify the spatial structure of species as random, aggregated or over-dispersed. Results We found consistent evidence among the eight sites for abundance--occupancy relationships to diverge significantly from the neutral model at the three spatial scales within each community. The direction that the slopes of relationships diverged from the neutral model provided consistent evidence that aggregation of individuals within species was responsible for modifying the form of abundance--occupancy associations in this vegetation, a feature most evident with increasing scale. Main conclusions Aggregation is not a mechanism that causes positive abundance--occupancy relationships. Under the neutral model of a positive abundance--occupancy relat [ABSTRACT FROM AUTHOR]

Paterson’s curse (Echium plantagineum L. (Boraginaceae)), is an herbaceous annual native to Western Europe and northwest Africa. It has been recorded in Australia since the 1800’s and is now a major weed in pastures and rangelands, but its introduction history is poorly understood. An understanding of its invasion pathway and subsequent genetic structure is critical to the successful introduction of biological control agents and for provision of informed decisions for plant biosecurity efforts. We sampled E. plantagineum in its native (Iberian Peninsula), non-native (UK) and invaded ranges (Australia and South Africa) and analysed three chloroplast gene regions. Considerable genetic diversity was found among E. plantagineum in Australia, suggesting a complex introduction history. Fourteen haplotypes were identified globally, 10 of which were co-present in Australia and South Africa, indicating South Africa as an important source population, likely through contamination of traded goods or livestock. Haplotype 4 was most abundant in Australia (43%), and in historical and contemporary UK populations (80%), but scarce elsewhere (< 17%), suggesting that ornamental and/or other introductions from genetically impoverished UK sources were also important. Collectively, genetic evidence and historical records indicate E. plantagineum in southern Australia exists as an admixture that is likely derived from introduced source populations in both the UK and South Africa. [ABSTRACT FROM AUTHOR]

Invasive grass weeds reduce farm productivity, threaten biodiversity, and increase weed control costs. Identification of invasive grasses from native grasses has generally relied on the morphological examination of grass floral material. DNA barcoding may provide an alternative means to identify co-occurring native and invasive grasses, particularly during early growth stages when floral characters are unavailable for analysis. However, there are no universal loci available for grass barcoding. We herein evaluated the utility of six candidate loci (atpF intron, matK, ndhK-ndhC, psbE—petL, ETS and ITS) for barcode identification of several economically important invasive grass species frequently found among native grasses in eastern Australia. We evaluated these loci in 66 specimens representing five invasive grass species (Chloris gayana, Eragrostis curvula, Hyparrhenia hirta, Nassella neesiana, Nassella trichotoma) and seven native grass species. Our results indicated that, while no single locus can be universally used as a DNA barcode for distinguishing the grass species examined in this study, two plastid loci (atpF and matK) showed good distinguishing power to separate most of the taxa examined, and could be used as a dual locus to distinguish several of the invasive from the native species. Low PCR success rates were evidenced among two nuclear loci (ETS and ITS), and few species were amplified at these loci, however ETS was able to genetically distinguish the two important invasive Nassella species. Multiple loci analyses also suggested that ETS played a crucial role in allowing identification of the two Nassella species in the multiple loci combinations. [ABSTRACT FROM AUTHOR]

Species delimitation has seen a paradigm shift as increasing accessibility of genomic-scale data enables separation of lineages with convergent morphological traits and the merging of recently diverged ecotypes that have distinguishing characteristics. We inferred the process of lineage formation among Australian species in the widespread and highly variable genus Pelargonium by combining phylogenomic and population genomic analyses along with breeding system studies and character analysis. Phylogenomic analysis and population genetic clustering supported seven of the eight currently described species but provided little evidence for differences in genetic structure within the most widely distributed group that containing P. australe. In contrast, morphometric analysis detected three deep lineages within Australian Pelargonium; with P. australe consisting of five previously unrecognized entities occupying separate geographic ranges. The genomic approach enabled elucidation of parallel evolution in some traits formerly used to delineate species, as well as identification of ecotypic morphological differentiation within recognized species. Highly variable morphology and trait convergence each contribute to the discordance between phylogenomic relationships and morphological taxonomy. Data suggest that genetic divergence among species within the Australian Pelargonium may result from allopatric speciation while morphological differentiation within and among species may be more strongly driven by environmental differences. [ABSTRACT FROM AUTHOR]

A general prediction of ecological theory is that climate change will favor invasive nonindigenous plant species (NIPS) over native species. However, the relative fitness advantage enjoyed by NIPS is often affected by resource limitation and potentially by extreme climatic events such as drought. Genetic constraints may also limit the ability of NIPS to adapt to changing climatic conditions. In this study, we investigated evidence for potential NIPS advantage under climate change in two sympatric perennial stipoid grasses from southeast Australia, the NIPS Nassella neesiana and the native Austrostipa bigeniculata. We compared the growth and reproduction of both species under current and year 2050 drought, temperature and CO2 regimes in a multifactor outdoor climate simulation experiment, hypothesizing that NIPS advantage would be higher under more favorable growing conditions. We also compared the quantitative variation and heritability of growth traits in populations of both species collected along a 200 km climatic transect. In contrast to our hypothesis we found that the NIPS N. neesiana was less responsive than A. bigeniculata to winter warming but maintained higher reproductive output during spring drought. However, overall tussock expansion was far more rapid in N. neesiana, and so it maintained an overall fitness advantage over A. bigeniculata in all climate regimes. N. neesiana also exhibited similar or lower quantitative variation and growth trait heritability than A. bigeniculata within populations but greater variability among populations, probably reflecting a complex past introduction history. We found some evidence that additional spring warmth increases the impact of drought on reproduction but not that elevated atmospheric CO2 ameliorates drought severity. Overall, we conclude that NIPS advantage under climate change may be limited by a lack of responsiveness to key climatic drivers, reduced genetic variability in range-edge populations, and complex drought-CO2 interactions. [ABSTRACT FROM AUTHOR]

Australia has a very diverse pea-flowered legume flora with 1715 native and naturalised species currently recognised. Tribe Mirbelieae s.l. includes 44% of Australia's peas in 24 genera with 756 recognised species. However, several genera within the Pultenaea alliance in tribe Mirbelieae are considered to be non-monophyletic and two main options have been proposed: option one is to merge ca. 18 genera containing ca. 540 species (the largest genus, Pultenaea has nomenclatural priority); and option two is to re-circumscribe some genera and describe new genera as required to form monophyletic groups. At the species level, option one would require 76% of names to be changed; whereas based on available data, option two is likely to require, at most, 8.3% of names to change. Option two therefore provides the least nomenclatural disruption but cannot be implemented without a robust phylogenetic framework to define new generic limits. Here we present novel analyses of available plastid DNA data (trnL-F) which suggest that option two would be feasible once sufficient data are generated to resolve relationships. However, the reticulate evolutionary histories or past rapid speciation suggested for this group may prevent the resolution of all nodes. We propose targeted use of Next-Generation Sequencing technology as the best way to resolve relationships between the key clades in the tribe and present a framework for such a study. An overview of current taxonomy in the tribe is presented, along with the state of taxonomic knowledge and availability of published descriptions for electronic flora treatments. Several new combinations and typifications are published in an appendix. [ABSTRACT FROM AUTHOR]

Echium plantagineum and E. vulgare are congeneric exotics first introduced to Australia in the early 1800 s. There, E. plantagineum is now highly invasive, whereas E. vulgare has a limited distribution. Studies were conducted to evaluate distribution, ecology, genetics and secondary chemistry to shed light on factors associated with their respective invasive success. When sampled across geographically diverse locales, E. plantagineum was widespread and exhibited a small genome size (1 C = 0.34 pg), an annual life cycle, and greater genetic diversity as assessed by DNA sequence analysis. It was found frequently in areas with temperature extremes and low rainfall. In contrast, E. vulgare exhibited a larger genome size (1 C = 0.43 pg), a perennial lifecycle, less chloroplast genetic diversity, and occurred in areas with lower temperatures and higher rainfall. Twelve chloroplast haplotypes of E. plantagineum were evident and incidence aligned well with reported historical introduction events. In contrast, E. vulgare exhibited two haplotypes and was found only sporadically at higher elevations. Echium plantagineum possessed significantly higher levels of numerous pyrrolizidine alkaloids involved in plant defence. We conclude that elevated genetic diversity, tolerance to environmental stress and capacity for producing defensive secondary metabolites have contributed to the successful invasion of E. plantagineum in Australia. [ABSTRACT FROM AUTHOR]