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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]

Classifications of the pantropical plant family Sapotaceae based solely on morphology have historically recognized between 125 and 53 genera. Phylogenetic analyses using molecular data have repeatedly demonstrated that broad concepts of two large genera belonging to subfamily Chrysophylloideae, Chrysophyllum and Pouteria, are untenable and their narrowed delimitations have restricted them to the Neotropics. A recent phylogenetic study proposed further amendments by resurrecting the genera Achrouteria, Cornuella, Lucuma, Martiusella, Nemaluma, Prieurella and Ragala, and questioned the status of three generally accepted genera, Chromolucuma, Pradosia and Sarcaulus. We test this suggested classification using expanded sampling that comprises 122 terminals, including material of 29 of the 34 name‐bringing species for generic names historically regarded as synonyms of Chrysophyllum and Pouteria. We used sequence data from ribosomal nrDNA (ETS, ITS), the nuclear gene RPB2, two cpDNA spacers (petN‐psbM, trnH‐psbA), and indel information to estimate phylogenetic relationships in a Bayesian framework using BEAST. All sequences were newly realigned to test reproducibility, and 26 morphological characters were mapped on the resulting tree. Our analyses recovered three African genera embedded within a large Neotropical clade of Chrysophylloideae. We found strong support for the reinstatement of the seven genera listed above as well as for four other genera, viz. Chloroluma, Englerella, Labatia, and Peteniodendron. This subsequently leads to further amendments of Chrysophyllum and Pouteria, which are now limited to include 25–30 and 7 species, respectively. However, one clade that includes many name‐bringing lineages largely corresponds to Pouteria s.l., a group that needs further phylogenetic research to unravel relationships and generic limits. The hypothesis that Chrysophyllum cuneifolium had an inter‐continental hybrid origin involving genomes from Africa and South America is rejected because it is shown to have been based on erroneous results obtained from a contaminated DNA aliquot. A total of 73 genera are currently recognised in Sapotaceae, 21 of which are Neotropical members of Chrysophylloideae. We update the nomenclature and synonymy of 75 species, make 36 new combinations, and designate lectotypes for 31 names. [ABSTRACT FROM AUTHOR]

Pouteria splendens is the only native species of Sapotaceae in Chile, a species once placed in the monotypic genus Gayella and known as G. valparadisaea, but for a long time treated as a Pouteria. In a phylogenetic analysis, this species was placed in an Australasian clade, not with its presumed relatives in South America. We used Bayesian inference under a relaxed molecular clock in BEAST, nuclear ribosomal DNA (ETS, ITS), the nuclear gene RPB2, indel information, and 201 terminals to find the closest relative of P. splendens and to estimate the age of the disjunction between Australasia and South America. The taxon has an isolated phylogenetic position, being part of the cladeʼs backbone, and is placed with weak support as sister to Van‐royena, another monotypic genus, but endemic to Australia. Our results justify reinstatement of Gayella with its single species G. valparadisaea. Gayella has a unique combination of morphological features including alternate, opposite or 3‐whorled leaves, often on the same plant, a usually 6‐lobed, rotate corolla with revolute corolla lobes giving the flower a star‐like appearance, lacerate to dentate staminodes, and yellow‐orange‐red fruit with plano‐convex cotyledons and an exserted radicle below the cotyledon commissure. The split between Gayella and Van‐royena is estimated to the late Eocene at about 40.0 Ma (50.5–25.3 Ma). The hypothesis that the presence of Gayella in South America is a result of vicariance is consistent with the timing of the geological splits of southern Gondwana, as well as with evidence from fossil pollen, but long‐distance dispersal is an alternative explanation that cannot be excluded. Gayella is restricted to an area with a Mediterranean‐type climate in coastal central Chile, where it occurs in rocky places, ravines, and gullies, usually below 100 m altitude within reach of sea mist. Gayella valparadisaea is a rare plant, listed as Endangered (EN) in Chile, but it does not occur in any protected area. Considering the isolated phylogenetic position of this old lineage, we urge the Chilean authorities to increase the efforts towards protection of this species. [ABSTRACT FROM AUTHOR]

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]

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]

As part of our ongoing molecular systematic research into the phylogeny of the Lamiales, we have conducted an investigation of the hypothesis put forward by Cantino that the Australian endemic labiate tribe Westringieae (= Prostanthereae) and the Australian endemic verbenaceous tribe Chloantheae together form a monophyletic group, which also included Tectona (Verbenaceae/Viticoideae sensu Briquet). The evidence for this postulated relationship comes from a cladistic analysis of morphological and anatomical characters, in which members of these two groups come out adjacent to each other in an unrooted tree. A total of 58 sequences was analysed, including the 24 sequences representing Chloantheae and Westringieae, along with 33 sequences representing species from throughout the Lamiaceae (including Spartothamnella) and related families. The results provide strong support for monophyletic groups comprising Chloantheae, Westringieae, and those two clades combined (Prostantheroideae). Tectona is not found to belong to this group. Spartothamnella is found to not belong with the Prostantheroideae, but belongs in Teucrioideae. It is sister to another Australian endemic, Oncinocalyx, and together they are sister to the New Zealand endemic Teucridium. These three taxa, all formerly assigned to Verbenaceae, are most closely related to Teucrium, traditionally assigned to Lamiaceae.

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]

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]

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]

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]

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]

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]

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]