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In Australia, Poaceae tribe Poeae are represented by 19 genera and 99 species, including economically and environmentally important native and introduced pasture grasses [e.g. Poa (Tussock-grasses) and Lolium (Ryegrasses)]. We used this tribe, which are well characterised in regards to morphological diversity and evolutionary relationships, to test the efficacy of DNA barcoding methods. A reference library was generated that included 93.9% of species in Australia (408 individuals, = 3.7 individuals per species). Molecular data were generated for official plant barcoding markers (rbcL, matK) and the nuclear ribosomal internal transcribed spacer (ITS) region. We investigated accuracy of specimen identifications using distance- (nearest neighbour, best-close match, and threshold identification) and tree-based (maximum likelihood, Bayesian inference) methods and applied species discovery methods (automatic barcode gap discovery, Poisson tree processes) based on molecular data to assess congruence with recognised species. Across all methods, success rate for specimen identification of genera was high (87.5–99.5%) and of species was low (25.6–44.6%). Distance- and tree-based methods were equally ineffective in providing accurate identifications for specimens to species rank (26.1–44.6% and 25.6–31.3%, respectively). The ITS marker achieved the highest success rate for specimen identification at both generic and species ranks across the majority of methods. For distance-based analyses the best-close match method provided the greatest accuracy for identification of individuals with a high percentage of “correct” (97.6%) and a low percentage of “incorrect” (0.3%) generic identifications, based on the ITS marker. For tribe Poeae, and likely for other grass lineages, sequence data in the standard DNA barcode markers are not variable enough for accurate identification of specimens to species rank. For recently diverged grass species similar challenges are encountered in the application of genetic and morphological data to species delimitations, with taxonomic signal limited by extensive infra-specific variation and shared polymorphisms among species in both data types. [ABSTRACT FROM AUTHOR]

The Australasian region contains a significant proportion of worldwide Poa diversity, but the evolutionary relationships of taxa from this region are incompletely understood. Most Australasian species have been placed in a monophyletic Poa subgenus, Poa supersection Homalopoa section Brizoides clade, but with limited resolution of relationships. In this study, phylogenetic relationships were reconstructed for Australasian Poa, using three plastid ( rbc L and mat K genes and the rpl32-trn L intergenic spacer) and two nuclear [internal/external transcribed spacer ( ITS/ ETS)] markers. Seventy-five Poa spp. were represented (including 42 Australian, nine New Guinean, nine New Zealand and three Australian/ New Zealand species). Maximum parsimony, maximum likelihood and Bayesian inference criteria were applied for phylogenetic reconstruction. Divergence dates were estimated using Bayesian inference, with a relaxed clock applied and rates sampled from an uncorrelated log-normal distribution. Australasian Poa spp. are placed in three lineages (section Brizoides, section Parodiochloa and the ' X clade'), each of which is closely related to non- Australasian taxa or clades. Section Brizoides subsection Australopoa is polyphyletic as currently circumscribed. In Australasia, Poa has diversified within the last 4.3 Mya, with divergence dating results broadly congruent with fossil data that record the appearance of vegetation with a prominent grassland understorey or shrubland/grassland mosaic vegetation dating from the mid-Pliocene. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 175, 523-552. [ABSTRACT FROM AUTHOR]

Advances in high-throughput, comprehensive small molecule analytical techniques have seen the development of the field of metabolomics. The coupling of mass spectrometry with high-resolution chromatography provides extensive chemical profiles from complex biological extracts. These profiles include thousands of compounds linked to gene expression, and can be used as taxonomic characters. Studies have shown metabolite profiles to be taxon specific in a range of organisms, but few have investigated taxonomically problematic plant taxa. This study used a phenetic analysis of metabolite profiles to test taxonomic boundaries in the Oleariaphlogopappa (Asteraceae) complex as delimited by morphological data. Metabolite profiles were generated from both field- and shade house-grown material, using liquid chromatography-mass spectrometry (LC-MS). Aligned profiles of 51 samples from 12 taxa gave a final dataset of over 10,000 features. Multivariate analyses of field and shade house material gave congruent results, both confirming the distinctiveness of the morphologically defined species and subspecies in this complex. Metabolomics has great potential in alpha taxonomy, especially for testing the boundaries of closely related taxa where DNA sequence data has been uninformative. [ABSTRACT FROM AUTHOR]

A morphometric study of the Olearia phlogopappa species complex from throughout south-eastern Australia has confirmed species boundaries and resolved the infraspecific taxonomy of two species. It has shown O. phlogopappa (Labill.) DC., O.stellulata (Labill.) DC., O. lirata (Sims) Hutch., O. rugosa (F. Muell.ex W. Archer bis) Hutch. and O. brevipedunculata N.G.Walshto be non-overlapping entities with unique morphological characters. O. stellulata is circumscribed to include only southern and western Tasmanian populations and those from the Otways and Wilsons Promontory in southern Victoria. O. rugosa is restricted to Victoria and a few isolated populations on Flinders Island and northern Tasmania. Four previously noted variants of O. rugosa from Victoria are here described as subspecies, along with the description of a fifth subspecies from northern Tasmania. Infraspecific boundaries of O. phlogopappa are here revised to include nine subspecies, six of which were previously included as varieties, and descriptions are made of three new subspecies. [ABSTRACT FROM AUTHOR]

We use data from 13 mountain regions and surrounding lowland areas to identify (1) the origins, traits and cultural uses of alien plant species that establish in mountains, (2) the alien species that are most likely to be a threat and (3) how managers might use this information to prevent further invasions. Australia, Canada, Chile, India, New Zealand, South Africa, Spain, Switzerland, USA. Lists of alien species were compiled for mountains and their surrounding or nearby lowlands. Principal co-ordinates analysis was performed on a matrix of similarities created using presence/absence data for alien species. The significance of differences between means for (1) similarity metrics of lowland and mountain groups and (2) species traits of lowland and mountain alien floras was determined using t-tests. In seven of the 13 mountain regions, lists of alien species undergoing management were compiled. The significance of differences between proportions of traits for species requiring and not requiring management input was determined with chi-square tests. We found that the proximal lowland alien flora is the main determinant of a mountain region's alien species composition. The highest similarities between mountain floras were in the Americas/Pacific Region. The majority of alien species commonly found in mountains have agricultural origins and are of little concern to land managers. Woody species and those used for ornamental purposes will often pose the greatest threat. Given the documented potential threat of alien species invading mountains, we advise natural resource managers to take preventive measures against the risk of alien plant invasion in mountains. A strategy for prevention should extend to the surrounding lowland areas and in particular regulate the introduction of species that are already of management concern in other mountains as well as climatically pre-adapted alien mountain plants. These may well become more problematic than the majority of alien plants currently in mountains. [ABSTRACT FROM AUTHOR]

The article offers information on Rorippa dictyosperma and Rorippa cygnorum. Topics discussed include various studies conducted to examine both Rorippa species, characteristics of seeds of both species and seeds collection of both species. It is noted that fresh seeds shed from mature, dehisced pods of Rorippa are mucous and sticky to the touch and this feature can not be used to discriminate either species from related, non-mucous taxa in the genus.

Lobelia claviflora Albr. & R.W.Jobson sp. nov. is described and illustrated, with notes on distribution, habitat, conservation status and features distinguishing it from closely related species of Lobelia and Isotoma. [ABSTRACT FROM AUTHOR]

Hibbertia circinata K.L.McDougall & G.T.Wright (Dilleniaceae: subgen. Hibbertia), a rare, geographically restricted species, is described as new. It is compared with H. linearis DC. and H. saligna DC., and its ecology and conservation status are discussed. [ABSTRACT FROM AUTHOR]

Abstract: A total of 128 invasive plant species have been recorded in treeless vegetation in the Australian Alps. Most of these are forbs and most are uncommon. Cover of invasive species is generally minimal unless there has been gross disturbance to natural vegetation and soils. Although there is a significantly positive correlation between invasive and native species diversity, suggesting that conditions that allow numerous native species to co-exist also permit more plant invasions, altitude is the most important determinant of invasive species diversity. Only 22 of the 128 species have been recorded above 1800m. Some plant communities (e.g. those with high pH or relatively nutrient-rich soils), however, seem to be vulnerable to invasions regardless of altitude. Most invasive species appear to have been introduced unintentionally (e.g. as seed attached to vehicles, animals and humans) but a few were introduced to assist with revegetation of disturbed soils and for amenity plantings in ski resorts, and have subsequently established in native vegetation. Treeless communities in the Australian Alps are likely to face increasing pressure from invasive species as a result of global warming and continued introduction of non-native plants to ski resort gardens. Whilst it may be difficult to prevent invasive species of low elevations migrating to higher elevations as temperatures rise, the risk of invasion from garden plants could be minimised through regulation. Non-native plants in ski resort gardens pose a far greater risk than most invasive species currently present in the Alps because they have been chosen for their capacity to survive at high altitudes. [Copyright &y& Elsevier]