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Spyridium Fenzl is a genus of ~45 species endemic to south-western and south-eastern Australia. This study provides the most comprehensive phylogenies of Spyridium to date, analysing both entire chloroplast genomes and the nuclear ribosomal array (18S–5.8S–26S). There was substantial incongruence between the chloroplast and nuclear phylogenies, creating phylogenetic uncertainty, but some clear relationships and biogeographic patterns could be established. Analyses support the monophyly of Spyridium, identifying an early east–west split at the base of the nuclear phylogeny and deep divergences of New South Wales and Tasmanian endemic clades. We also found evidence of more recent dispersal events between eastern and western Australia and between Tasmania and the mainland. Eleven taxa were found to be monophyletic in the nrDNA phylogeny and two were clearly polyphyletic (S. eriocephalum Fenzl and S. phylicoides Reissek). Although the polyphyly of S. eriocephalum correlates with the two varieties, suggesting distinct taxa, further research is required on S. phylicoides.

Context: Fewer than 10 plant species from Australia were known to hyperaccumulate metal(loid)s, despite metal-rich soils being widespread in Australia. By measuring herbarium specimens with non-destructive portable X-ray fluorescence spectroscopy (XRF) instrumentation their metal(loid)s concentrations can be determined, providing information that could be used to probe the evolution, biogeography, ecology, and physiology of plant species.Aims: This study aimed to systematically measure herbarium specimens to obtain information on the prevailing concentrations of metal(loid)s in nearly 7000 plant specimens across seven plant families, and to link this data to an assessment of their spatial distribution.Methods: The raw XRF spectrum of each herbarium specimen was processed using a new data-analysis pipeline recently validated for XRF data of herbarium specimens, to determine the concentrations of the first-row metal transition elements, and other detected elements. The collection localities of each of the herbarium specimens were plotted against rainfall and soil types to assess possible distributional patterns.Key results: The results showed several newly discovered hyperaccumulator plant species, including 15 for manganese, two for nickel, three for cobalt, three for zinc, two for rare earth elements and one for selenium.Conclusions and implications: Australia has more hyperaccumulator plant species than previously known and the XRF analysis of herbarium specimens is a powerful tool for their discovery. This research presents a new value proposition for the continued funding of herbarium collections in Australia and could initiate a range of research opportunities to use these data for future studies of plant evolution and adaptation.

The flora of Papua New Guinea is amongst the richest in the world with an estimated 25,000 plant species. The extreme levels of biodiversity, climatic ranges and soil types suggest a high possibility of metal hyperaccumulator plants existing in Papua New Guinea. However, no hyperaccumulator plants have been reported from this region yet. The use of handheld X-ray fluorescence instruments is a non-destructive and effective method for the systematic quantitative assessment of hyperaccumulation in vast numbers of herbarium specimens. X-ray fluorescence scanning was undertaken at the Queensland Herbarium (Australia) on all Papua New Guinea specimens from seven major families (Celastraceae, Cunoniaceae, Phyllanthaceae, Proteaceae, Rubiaceae, Salicaceae and Violaceae), covering 3164 plant specimens. This preliminary survey revealed the existence of ten zinc hyperaccumulator species (> 3000 µg g−1 Zn), eight manganese accumulator species (> 5000 µg g−1 Mn) and one nickel hyperaccumulator species (> 1000 µg g−1 Ni). These results highlight the potential for discovery of numerous new metal hyperaccumulator plants from the flora of Papua New Guinea if larger-scale systematic screening efforts were undertaken.

© The Willi Hennig Society 2011. Abstract Paraserianthes (tribe Ingeae) as circumscribed by Nielsen et al. includes four species and five subspecies in two sections endemic to Australia, Indonesia, New Guinea and the Solomon islands. An alternative classification, proposed by Barneby and Grimes, raised Nielsen’s two sections to generic level, thereby reducing Paraserianthes to comprise just species, P. lophantha, and recognizing the genus Falcataria. Neither treatment has been adopted by all. Thus, a phylogenetic and systematic analysis of Paraserianthes is required to clarify the taxonomic circumscription of the genus and relationships among the species and subspecies. Furthermore, elucidation of the phylogenetic relationships of Paraserianthes is significant to an understanding of the evolutionary history and biogeography of Acacia sensu stricto (s.s.). The external transcribed spacer regions of nuclear ribosomal DNA and the rpl32-trnL intergenic spacer of chloroplast DNA were sequenced for all species of Paraserianthes, a representative sample of Acacia s.s. (phyllodinous group) and 18 other members of tribe Ingeae, including an outgroup Samanea tubulosa. These data were analysed with parsimony and Bayesian methods. The topologies of the resultant phylogenetic trees were congruent but with greater resolution in the Bayesian tree. The results show that Paraserianthes sensu Nielsen is paraphyletic and that P. lophantha is the sister group to Acacia, a finding supported by morphological characters. Paraserianthes shows a dual link between Australia and lands to the north. A western biogeographical track relates south-west Western Australia to Sumatra, Java, Bali and Flores (two subspecies of P. lophantha), and an eastern track relates north-east Queensland to the Moluccas, New Guinea, the Bismarck Archipelago and the Solomon Islands (P. toona and its relatives).

The rare phenomenon of plant manganese (Mn) hyperaccumulation within the Australian flora has previously been detected in the field, which suggested that the tree genus Gossia (Myrtaceae) might contain new Mn hyperaccumulators. We conducted the first growth experiment on Gossia using a multi-factorial dosing trial to assess Mn, cobalt (Co), and zinc (Zn) (hyper)accumulation patterns in selected Gossia species (G. fragrantissima and G. punctata) after a systematic assessment of elemental profiles on all holdings of the genus Gossia at the Queensland Herbarium using handheld X-ray fluorescence spectroscopy. We then conducted detailed in situ analyses of the elemental distribution of Mn, Co, Zn and other elements at the macro (organ) and micro (cellular) levels with laboratory- and synchrotron-based X-ray fluorescence microscopy (XFM). Gossia pubiflora and Gossia hillii were newly discovered to be Mn hyperaccumulator plants. In the dosing trial, G. fragrantissima accumulated 17 400 µg g−1 Mn, 545 µg g−1 Co, and 13 000 µg g−1 Zn, without signs of toxicity. The laboratory-based XFM revealed distinct patterns of accumulation of Co, Mn, and Zn in G. fragrantissima, while the synchrotron XFM showed their localization in foliar epidermal cells, and in the cortex and phloem cells of roots. This study combined novel analytical approaches with controlled experimentation to examine metal hyperaccumulation in slow-growing tropical woody species, thereby enabling insight into the phenomenon not possible through field studies.

International audience; Background and aims: The genus Denhamia(Celastraceae) includes fifteen Australian species, many of which have a propensity for manganese (Mn) (hyper)accumulation. Among the key aims of this study were to: i) elucidate Mn accumulation in D. bilocularis, D. celastroides, D. pittosporoides and D. silvestris under controlled conditions; ii) examine the in situ distributions of Mn and other elements in tissues of i) above, and also in two other species growing in their natural habitat, i.e. D. silvestris and D. cunninghamii; iii) test numerous Denhamia herbarium specimens for Mn accumulation using portable X-ray fluorescence spectroscopy (XRF).Methods: Portable XRF and laboratory micro-XRF were used to examine Mn accumulation and foliar distribution patterns in several Australian Denhamia species. These techniques were variously applied to fresh field material and experimentally-raised plants treated with Mn (250 μg g−1, 500 μg g−1 and 1000 μg g−1) and dry herbarium material.Results: The findings revealed D. bilocularis as a new Mn hyperaccumulator, with foliar Mn concentrations of up to 15,300 μg g−1 in herbarium samples, and 13,700 μg g−1 in experimentally grown plants. Laboratory μXRF maps consistently showed that foliar Mn accumulation was localized at the extremities of wild D. cunninghamii and D. silvestris leaves; whereas it was found in the vasculature of experimentally grown D. bilocularis and D. pittosporoides leaves.Conclusions: This study presents evidence that Mn accumulation across the Australian Denhamia species is taxonomically variable, however further work is required.

Premise of the study: Targeted enrichment methods facilitate sequencing of hundreds of nuclear loci to enhance phylogenetic resolution and elucidate why some parts of the Tree of Life are difficult (if not impossible) to resolve. The mimosoid legumes are a prominent pantropical clade of c. 3300 species of woody angiosperms for which previous phylogenies have shown extensive lack of resolution, especially among the species-rich and taxonomically challenging ingoids.Methods: We generate transcriptomes to select low-copy nuclear genes, enrich the sevia hybrid capture for representative species of most mimosoid genera and analyse the resulting data using de novo assembly and various phylogenomic tools for species tree inference. We also evaluate gene tree support and conflict for key internodes and use phylogenetic network analysis to investigate phylogenetic signal across the ingoids. Key results: Our selection of 964 nuclear genes greatly improves phylogenetic resolution across the mimosoid phylogeny and shows that the ingoid clade can be resolved into several well-supported clades. However, nearly all loci show lack of phylogenetic signal for some of the deeper internodes within the ingoids. Conclusions: Lack of resolution in the ingoid clade is most likely the result of hyper-fast diversification, potentially causing a hard polytomy of six or seven lineages. The gene set for targeted sequencing presented here offers great potential to further enhance the phylogeny of mimosoids and the wider Caesalpinioideae with denser tax on sampling, to provide a framework for taxonomic reclassification, and to study the ingoid radiation.

Paraseriantheslophantha subsp. lophantha (Leguminosae) is native to southwestern Australia, but has become naturalized in eastern Australia and in countries around the world. Previous studies have investigated the introduction sources for P. lophantha subsp. lophantha overseas, but here, we expand on the knowledge of genetic patterns in its native and naturalized range in Australia. Genetic patterns were examined using nine nuclear microsatellite loci and three chloroplast DNA markers. The native populations exhibited phylogeographic patterns, including north-south differentiation, and a genetic signal related to temperature gradients. Naturalized Australian populations displayed lower overall genetic variation and no phylogeographic patterns. Several naturalized populations separated by large distances (350&ndash, 650 km) shared multi-locus genotypes, supporting the notion of a shared source of germplasm and possible inbreeding due to human-mediated introductions from a limited number of individuals and/or source populations within the native range. We advocate that management strategies are tailored to the distinct conservation aims underpinning conservation in native or naturalized populations. Within the native distribution, management should have a long-term aim to replicate historical evolutionary processes, whereas in naturalized populations, immediate actions may be required to reduce the abundance of P. lophantha subsp. lophantha and minimize its invasive impact on the recipient vegetation

Selenium (Se), a trace element essential for human and animal biological processes, is deficient in many agricultural soils. Some extremely rare plants can naturally accumulate extraordinarily high concentrations of Se. The native legume Neptunia amplexicaulis, endemic to a small area near Richmond and Hughenden in Central Queensland, Australia, is one of the strongest Se hyperaccumulators known on Earth, with foliar concentrations in excess of 4000 μg Se g−1 previously recorded. Here, we report on the Se distribution at a whole plant level using laboratory micro X-ray Fluorescence Microscopy (μXRF) and scanning electron microscopy (SEM-EDS), as well as on chemical forms of Se in various tissues using liquid chromatography-mass spectrometry (LC-MS) and synchrotron X-ray absorption spectroscopy (XAS). The results show that Se occurs in the forms of methyl-selenocysteine and seleno-methionine in the foliar tissues, with up to 13 600 μg Se g−1 total in young leaves. Selenium was found to accumulate primarily in the young leaves, flowers, pods and taproot, with lower concentrations present in the fine-roots and stem and the lowest present in the oldest leaves. Trichomes were not found to accumulate Se. We postulate that Se is (re)distributed in this plant via the phloem from older leaves to newer leaves, using the taproot as the main storage organ. High concentrations of Se in the nodes (pulvini) indicate this structure may play an important a role in Se (re)distribution. The overall pattern of Se distribution was similar in a non-Se tolerant closely related species (Neptunia gracilis), although the prevailing Se concentrations were substantially lower than in N. amplexicaulis.

The classification of the legume family proposed here addresses the long-known non-monophyly of the traditionally recognised subfamily Caesalpinioideae, by recognising six robustly supported monophyletic subfamilies. This new classification uses as its framework the most comprehensive phylogenetic analyses of legumes to date, based on plastid matK gene sequences, and including near-complete sampling of genera (698 of the currently recognised 765 genera) and ca. 20% (3696) of known species. The matK gene region has been the most widely sequenced across the legumes, and in most legume lineages, this gene region is sufficiently variable to yield well-supported clades. This analysis resolves the same major clades as in other phylogenies of whole plastid and nuclear gene sets (with much sparser taxon sampling). Our analysis improves upon previous studies that have used large phylogenies of the Leguminosae for addressing evolutionary questions, because it maximises generic sampling and provides a phylogenetic tree that is based on a fully curated set of sequences that are vouchered and taxonomically validated. The phylogenetic trees obtained and the underlying data are available to browse and download, facilitating subsequent analyses that require evolutionary trees. Here we propose a new community-endorsed classification of the family that reflects the phylogenetic structure that is consistently resolved and recognises six subfamilies in Leguminosae: a recircumscribed Caesalpinioideae DC., Cercidoideae Legume Phylogeny Working Group (stat. nov.), Detarioideae Burmeist., Dialioideae Legume Phylogeny Working Group (stat. nov.), Duparquetioideae Legume Phylogeny Working Group (stat. nov.), and Papilionoideae DC. The traditionally recognised subfamily Mimosoideae is a distinct clade nested within the recircum-scribed Caesalpinioideae and is referred to informally as the mimosoid clade pending a forthcoming formal tribal and/or clade-based classification of the new Caesalpinioideae. We provide a key for subfamily identification, descriptions with diagnostic charactertistics for the subfamilies, figures illustrating their floral and fruit diversity, and lists of genera by subfamily. This new classification of Leguminosae represents a consensus view of the international legume systematics community; it invokes both compromise and practicality of use.

Reliance on clonal reproduction is associated with an increased risk of extinction. Grevillea infecunda is a rare, putatively sterile shrub restricted to 11 populations in a localized coastal region of south-eastern Australia. We assessed the genetic diversity, clonal diversity and spatial distribution of clones in all populations of G. infecunda to guide conservation management. Eight chloroplast haplotypes were identified from the trnL – trnF and trnQ – rps16 intergenic spacer regions. All individuals belonged to a single maternal lineage dominated by one haplotype (95/111 samples). Minor haplotypes differed from the common haplotype only by single mutational steps. However, microsatellite markers revealed 89 multilocus genotypes (MLGs) in 38 multilocus lineages (MLLs) of variable size. MLLs were not shared among populations and ramets from different MLLs rarely intermingled physically. New shoots arising after fire were confirmed to belong to previously-existing MLLs, indicating that this species exhibits adaptation to fire. Genetically similar MLGs were more likely to be found in close proximity than less similar MLGs, resulting in significant spatial autocorrelation to ca 350 m. Genetic diversity was moderate but genotypic diversity was low once likely clonality was taken into account. Clonality appears to have arisen several times within the holly-leafed grevilleas and examining G. infecunda is a step towards understanding why and how often clonality occurs, and the long-term evolutionary outcomes of this life history.

We assembled the complete chloroplast genome of the Australian shrub Spyridium parvifolium var. parvifolium. The genome was 161,012 bp in length, with a pair of inverted repeats (IRs) of 26,515 bp, separated by a large single copy (LSC) region of 88,814 bp and a small single copy region (SCC) of 19,168 bp. The GC content was 36.9%. In total, 130 genes were annotated, including 86 protein coding genes, 36 tRNA genes and 8 rRNA genes. Phylogenetic analysis of 56 chloroplast genes placed this genome of S. parvifolium var. parvifolium within the family Rhamnaceae.

Correa (family Rutaceae) is a genus endemic to southern Australia, in which chloroplast introgression between species has previously been inferred. The current study aimed to document the extent of incongruence between molecular markers and taxonomy, describe patterns of geographic variation, and infer genetic and biogeographic processes important in the history of the genus. Sampling focused on subg. Correa (nine species) and included 166 samples from 95 localities. Samples were genotyped at the chloroplast loci trnL-trnF and trnK and the nuclear ITS regions, either by direct sequencing or by restriction digests of PCR products. Both chloroplast and ITS datasets resolved subg. Persistens (two species mostly from wet forests) as distinct from those of subg. Correa. Within subg. Correa chloroplast and ITS lineages were largely incongruent with each other and with current taxonomy, but both datasets showed similar geographic patterns. In each dataset there was one lineage mostly restricted to western South Australia and Western Australia, and one lineage widespread in eastern South Australia, Victoria, Tasmania, New South Wales and Queensland. The split between these geographic lineages occurs in South Australia, on the western side of the Murray basin; it is sharply defined in the chloroplast results, whereas the distributions of ITS lineages overlap. The geographic patterns and incongruence exhibited by both ITS and chloroplast markers provide evidence for substantial chloroplast and nuclear introgression between species. Geographic distributions of genetic lineages are consistent with divergence caused by a historical vicariance event across the lower Murray basin and subsequent reconnection of populations.

We identified 14 informative microsatellite loci from two taxa, Grevillea aquifolium (6) and G. infecunda (8), belonging to the Pteridifolia Group, Aspleniifolia/Hookeriana Subgroup (Proteaceae). Loci were screened for variability among 20 individuals of their source species. The number of alleles observed per locus for G. infecunda ranged from 1 to 3. Subsequent chromosome counts revealed between 20 (normal diploid) and 30 (triploid) chromosomes in different individuals. High levels of variability were observed with the number of alleles per locus ranging from 3 to 17, with a mean of 9.8 across all loci. Nei’s genetic diversity (HE) ranged from 0.399 to 0.992 with a mean of 0.783. All loci amplified in a further 9–13 taxa from the same subgroup and under the same amplification conditions. These new markers provide useful tools for evolutionary and conservation studies assessing clonality and polyploidy in this important Australian genus.

Aim Acacia is the largest genus of plants in Australia with over 1000 species. A subset of these species is invasive in many parts of the world including Africa, the Americas, Europe, the Middle East, Asia and the Pacific region. We investigate the phylogenetic relationships of the invasive species in relation to the genus as a whole. This will provide a framework for studying the evolution of traits that make Acacia species such successful invaders and could assist in screening other species for invasive potential. Location Australia and global. Methods We sequenced four plastid and two nuclear DNA regions for 110 Australian Acacia species, including 16 species that have large invasive ranges outside Australia. A Bayesian phylogenetic tree was generated to define the major lineages of Acacia and to determine the phylogenetic placement of the invasive species. Results Invasive Acacia species do not form a monophyletic group but do form small clusters throughout the phylogeny. There are no taxonomic characters that uniquely describe the invasive Acacia species. Main conclusions The legume subfamily Mimosoideae has a high percentage of invasive species and the Australian Acacia species have the highest rate of all the legumes. There is some evidence of phylogenetic clumping of invasive species of Acacia in the limited sampling presented here. This phylogeny provides a framework for further testing of the evolution of traits associated with invasiveness in Acacia. © 2011 Blackwell Publishing Ltd.

Aim The genetic makeup and evolutionary potential of alien species can be profoundly influenced by their introduction history, but without detailed historical records, it can be difficult to ascertain the strength of this historical contingency. We explore how the known introduction histories combined with phylogeographic patterns in the native range have affected the genetic diversity in the invasive range for five Australian trees introduced to South Africa (Acacia cyclops, Acacia mearnsii, Acacia pycnantha, Acacia saligna and Paraserianthes lophantha). Location Western Australia, South Australia, Victoria and New South Wales (native and invasive ranges), and South Africa and the Hawaiian Islands (invasive range). Methods DNA sequence data were generated for all study species for either the external transcribed spacer (ETS) or plastid rpl32-trnL(UAG) gene regions (combined total of 180 DNA sequences). Using statistical parsimony networks and genetic diversity indices, we compared genetic structure and variation in native and invasive ranges. Results Australian acacia species tend to have high genetic diversity at the population level in their native ranges, often showing high intra-specific divergence. In most instances, these species have similar levels of population genetic diversity in their adventive ranges in South Africa, but lack structure. For A. cyclops, A. saligna and P. lophantha, we found evidence for intra-specific hybridization between mixed genetic entities in the invasive range, arguably as a result of the structured native range being broadly sampled prior to introduction. Main conclusions Invasive species that have been extensively used in forestry often have complex introduction histories resulting in equally complex genetic signatures in the invasive range. Our results show that extreme caution should be taken when using indirect inferences (molecular genetic data) of introduction histories in the absence of detailed introduction records.

Sequences of nuclear ribosomal DNA internal (ITS) and external (ETS) transcribed spacers were used to generate a phylogeny of Acacia Mill. s.str. (synonyms: Acacia subg. Phyllodineae (DC.) Seringe; Racoserma Mart.). This study included 109 exemplar taxa from all seven sections recognised in previous classifications, and represents the largest sampling of diversity for molecular phylogenetics of Acacia s.str. undertaken so far. Four main clades were identified from the combined dataset of ITS and ETS using parsimony and Bayesian analyses. Two of these clades consist mostly ofuninerved phyllodinous taxa assigned to sect. Phyllodineae. One clade includes taxa related to A. victoriae and A. pyrifolia, and the second comprises taxa in the A. murrayana species group. These taxa occur predominantly in semi-arid and arid regions. Relationships also resolve the previously identified Pulchelloidea clade, which includes members of sects. Pulchellae, Alatae, Phyllodineae and Lycopodiifoliae. A large clade with limited phylogenetic resolution was also identified (the "p.u.b. clade"). This is an assemblage of plurinerved and uninerved phyllodinous taxa and also bi-pinnate taxa from sect. Botrycephalae. Clades are discussed with reference to morphological characters, and while some morphological states are correlated with clades, including seedling ontogeny, inflorescence and phyllode nerves, clear synapomorphies remain to be identified. Traditional classifications of Acacia s.str. are artificial and a preliminary informal classification based on phylogenetic relationships within Acacia s.str. is proposed.

Resolving uncertainty surrounding the taxonomic and conservation status of rare plants is of utmost importance to enable effective allocation of the limited resources available for conserving biodiversity. Prioritising threatened taxa that are more appropriately regarded as synonymous with more common species represents a waste of resources. Such a scenario may apply to the Australian entity Grevillea williamsonii and consequently its taxonomic status was investigated using chloroplast DNA sequences and nuclear microsatellite data. Haplotype network and genetic structure analyses showed that G. williamsonii was not genetically distinct from, and should be synonymised with, the variable and morphologically similar but more common G. aquifolium. This study highlights the benefit of undertaking genetic analyses where questionable taxonomic status biases conservation prioritisation and management decisions.

A new classification of the Vireya group of Rhododendron, based upon their evolutionary relationships as inferred from analysis of nuclear and plastid DNA sequence data, is presented. Rhododendron sect. Vireya is not monophyletic and its species are herein placed in three sections within subg. Rhododendron, namely sect. Discovireya, sect. Pseudovireya and sect. Vireya, with two subsections recognised within sect. Vireya: subsect. Euvireya and subsect. Malayovireya. Identification keys are provided.

To search for the sister taxon of Acacia s.s. (tribe Acacieae) and to further knowledge of the phylogeny of the related tribe Ingeae, we have sequenced two regions of nuclear ribosomal DNA (ITS and ETS). Sixty species from tribe Ingeae (26 genera), together with representatives from each of five lineages of tribe Acacieae, have been sampled. Ingeae and Acacia s.s. form a well supported clade, with a monophyletic Acacia s.s. nested within a paraphyletic Ingeae. Based on our sampling, the closest relative of Acacia s.s. is most likely one of the Australian species of the genus Paraserianthes s.l.: Paras. lophantha subsp. lophantha or Paras. toona. Related to Acacia s.s. and Paraserianthes s.l. is a group of Ingeae from Australia and South East Asia: Archidendron p.p., Archidendropsis, Pararchidendron, and Wallaceodendron. This study is a preliminary step in resolving the intergeneric relationships of tribe Ingeae. Genetic relationships within Ingeae appear to conform to morphological groups previously identified as genera and informal alliances; some notable exceptions are discussed.

Aim Vireya rhododendrons are distinctive and easily recognizable by their general form; however, they are virtually circumscribed geographically, predominantly distributed throughout the biogeographically intriguing Malesian Archipelago. Hypotheses of the evolutionary relationships of the group have been proposed but the biogeography of vireyas has not been analysed based on molecular phylogeny. Recently, the first detailed molecular phylogenetic investigation of section Vireya was completed based on cp- and nrDNA sequence data, therefore making this cladistic biogeographic study of vireya rhododendrons possible. Location Malesia, Australia, Solomon Islands, Taiwan, Himalayas, north Vietnam and south China. Methods Based on distribution maps, areas of endemism were determined for the biogeographic region of Malesia. Area relationships were analysed based on a recent molecular phylogeny of species in section Vireya. The method of paralogy-free subtree analysis was applied. Results Individual distribution maps were produced for 74 species of Rhododendron section Vireya. Species clades with bootstrap support proved to be biogeographically informative. Major clades correspond to three regions: eastern Malesia, western/middle Malesia and Taiwan/north Vietnam/south China. Within eastern Malesia, Australia, New Guinea, the Bismarck Archipelago and Solomon Islands are related. In western Malesia, northern Philippines, Borneo, southern Moluccas and north and west Sulawesi are related. These areas are more distantly related to Sumatra, the Malay peninsula, Java, Bali, Palawan, Lesser Sunda islands and the southern Philippines. The position of the Himalayas is equivocal and part of a basal polytomy in the summary area cladogram. Main conclusions Two alternative hypotheses are proposed for the evolution of vireya rhododendrons based on the pattern of area relationships. The first hypothesis is that the vireyas are an old group, with ancestors present on Gondwana, rifting north in the Cretaceous. The second alternative hypothesis is that vireyas are a young group that has dispersed eastwards from India to Australia and the Solomon Islands since the current Malesian islands formed.

Section Vireya (Blume) Copel.f. is one of the most morphologically diverse groups of the genus Rhododendron. Vireyas have a unique distribution for the genus, being predominantly found throughout the Malesian Archipelago. The alpha taxonomy of section Vireya is relatively well understood and taxa are easily distinguished from other rhododendrons by their general appearance. Defining characteristics of the section the possession of seeds with tailed appendages at both ends, the twisting of capsule valves after opening, placentas that separate as thread-like structures from the central axis as the capsule opens are all subject to exceptions.

Ten microsatellite loci were developed for the grassland shrub Pimelea spinescens. Locus amplification varied between the two subspecies. For P. spinescens subsp. spinescens, nine loci amplified and were polymorphic. Number of alleles per locus ranged from two to eleven (average = 5.7) and expected heterozygosity ranged from 0.103 to 0.782. For P. spinescens subsp. pubiflora, seven loci amplified, of which only three were polymorphic. For polymorphic loci, number of alleles ranged from four to seven (average = 5.3) and expected heterozygosity ranged from 0.381 to 0.783. These loci will be used to investigate population genetic structure, assisting management of this endangered species.

Eleven polymorphic microsatellite loci were developed from the polyploid wetland plant Triglochin procera (Juncaginaceae). Loci were screened for variability among 20 individuals from each of two populations in Victoria, Australia. The number of alleles amplified per locus ranged from 5 to 17, with a mean of 9.5. Nei’s genetic diversity (H E ) ranged from 0.463 to 0.898 with a mean of 0.725. These primers provide the opportunity to use polymorphic DNA markers to study the population genetic structure, breeding system and dispersal in T. procera and related species.

Although temporal calibration is widely recognized as critical for obtaining accurate divergence-time estimates using molecular dating methods, few studies have evaluated the variation resulting from different calibration strategies. Depending on the information available, researchers have often used primary calibrations from the fossil record or secondary calibrations from previous molecular dating studies. In analyses of flowering plants, primary calibration data can be obtained from macro- and mesofossils (e.g., leaves, flowers, and fruits) or microfossils (e.g., pollen). Fossil data can vary substantially in accuracy and precision, presenting a difficult choice when selecting appropriate calibrations. Here, we test the impact of eight plausible calibration scenarios for Nothofagus (Nothofagaceae, Fagales), a plant genus with a particularly rich and well-studied fossil record. To do so, we reviewed the phylogenetic placement and geochronology of 38 fossil taxa of Nothofagus and other Fagales, and we identified minimum age constraints for up to 18 nodes of the phylogeny of Fagales. Molecular dating analyses were conducted for each scenario using maximum likelihood (RAxML + r8s) and Bayesian (BEAST) approaches on sequence data from six regions of the chloroplast and nuclear genomes. Using either ingroup or outgroup constraints, or both, led to similar age estimates, except near strongly influential calibration nodes. Using "early but risky" fossil constraints in addition to "safe but late" constraints, or using assumptions of vicariance instead of fossil constraints, led to older age estimates. In contrast, using secondary calibration points yielded drastically younger age estimates. This empirical study highlights the critical influence of calibration on molecular dating analyses. Even in a best-case situation, with many thoroughly vetted fossils available, substantial uncertainties can remain in the estimates of divergence times. For example, our estimates for the crown group age of Nothofagus varied from 13 to 113 Ma across our full range of calibration scenarios. We suggest that increased background research should be made at all stages of the calibration process to reduce errors wherever possible, from verifying the geochronological data on the fossils to critical reassessment of their phylogenetic position.

Acacia sensu stricto is found predominantly in Australia; however, there are 18 phyllodinous taxa that occur naturally outside Australia, north from New Guinea to Indonesia, Taiwan, the Philippines, south-western Pacific (New Caledonia to Samoa), northern Pacific (Hawaii) and Indian Ocean (Mascarene Islands). Our aim was to determine the phylogenetic position of these species within Acacia, to infer their biogeographic history. To an existing molecular dataset of 109 taxa of Acacia, we added 51 new accessions sequenced for the ITS and ETS regions of nuclear rDNA, including samples from 15 extra-Australian taxa. Data were analysed using both maximum parsimony and Bayesian methods. The phylogenetic positions of the extra-Australian taxa sampled revealed four geographic connections. Connection A, i.e. northern Australia?South-east Asia?south-western Pacific, is shown by an early diverging clade in section Plurinerves, which relates A. confusa from Taiwan and the Philippines (possibly Fiji) to A. simplex from Fiji and Samoa. That clade is related to A. simsii from southern New Guinea and northern Australia and other northern Australian species. Two related clades in section Juliflorae show a repeated connection (B), i.e. northern Australia?southern New Guinea?south-western Pacific. One of these is the ?A. auriculiformis clade', which includes A. spirorbis subsp. spirorbis from New Caledonia and the Loyalty Islands as sister to the Queensland species A. auriculiformis; related taxa include A. mangium, A. leptocarpa and A. spirorbis subsp. solandri. The ?A. aulacocarpa clade' includes A. aulacocarpa, A. peregrinalis endemic to New Guinea, A. crassicarpa from New Guinea and Australia, and other Australian species. Acacia spirorbis (syn. A. solandri subsp. kajewskii) from Vanuatu (Melanesia) is related to these two clades but its exact position is equivocal. The third biogeographic connection (C) is Australia?Timor?Flores, represented independently by the widespread taxon A. oraria (section Plurinerves) found on Flores and Timor and in north-eastern Queensland, and the Wetar island endemic A. wetarensis (Juliflorae). The fourth biogeographic connection (D), i.e. Hawaii?Mascarene?eastern Australia, reveals an extreme disjunct distribution, consisting of the Hawaiian koa (A. koa, A. koaia and A. kaoaiensis), sister to the Mascarene (R�union Island) species A. heterophylla; this clade is sister to the eastern Australian A. melanoxylon and A. implexa (all section Plurinerves), and sequence divergence between taxa is very low. Historical range expansion of acacias is inferred to have occurred several times from an Australian?southern New Guinean source. Dispersal would have been possible as the Australian land mass approached South-east Asia, and during times when sea levels were low, from the Late Miocene or Early Pliocene. The close genetic relationship of species separated by vast distances, from the Indian Ocean to the Pacific, is best explained by dispersal by Austronesians, early Homo sapiens migrants from Asia.

Seventeen Australian, phyllodinous species of Acacia s.s. (from sections Juliflorae and Phyllodineae) were analysed to test the monophyly and relationships of ‘the Acacia longifolia group’, an informal group recognised in the Flora of Australia. Analyses were based on both morphological and molecular data, with A. triptera as an outgroup. A total of 92 herbarium specimens was investigated, with 15 phyllode, inflorescence, flower, pod and seed characters scored. The ITS and ETS regions of nuclear rDNA were sequenced and combined with a larger dataset sampled from species of all major clades of Acacia, totalling 65 accessions. Cladistic analyses provided evidence of a clade that defines the A. longifolia group as follows: A. alpina, A. axillaris, A. courtii, A. dallachiana, A. derwentiana, A. floribunda, A. longifolia subsp. longifolia and A. longifolia subsp. sophorae, A. longissima, A. maidenii, A. mucronata, A. obtusifolia, A. orites, A. oxycedrus, A. phlebophylla, A. rhigiophylla and A. riceana (all sect. Juliflorae), but excluding A. verticillata (section Juliflorae) and A. genistifolia (section Phyllodineae). The A. longifolia group is recognised as including south-eastern Australian species with cylindrically spiked inflorescences and phyllodes with prominent anastomosing venation.

A phylogenetic analysis of Acacia subg. Phyllodineae sect. Botrycephalae, endemic to eastern Australia, is presented based on a combined dataset of ITS and ETS sequences of nrDNA. A smaller set of species was sequenced also for the cpDNA trnK region. A limited number of morphological characters was also combined with the ITS+ETS dataset for most taxa. Thirty-eight of 41 Botrycephalae species were sequenced, together with a sample of ten uninerved phyllodinous species (sect. Phyllodineae). Although these DNA regions showed limited sequence divergence, bootstrap supported nodes of the consensus ITS+ETS tree indicate that Botrycephalae as currently defined is polyphyletic. Eight bipinnate species fell outside the main clade of Botrycephalae species while seven phyllodinous species were nested within it, near the base. The few derived but homoplasious morphological characters that were discovered included: presence of appressed unicellular hairs, presence of jugary and interjugary glands, number of pinnae > 7 and the funicle half–fully encircling the seed. Section Botrycephalae requires redefinition.

Rhododendron L. taxonomy has been tested in recent times by molecular phylogenies based on several DNA regions. Most of these studies have aimed at higher-level relationships, despite the importance of lower ranks, such as sections, to most workers on the genus. Almost one-third of the species of Rhododendron are placed in one of the lepidote (scaly) sections, section Vireya (Blume) Copel.f. Results of phylogenetic analyses of the ITS region (ITS-1, 5.8S and ITS-2) for the genus Rhododendron, with sampling concentrated on section Vireya, are presented. The results of Bayesian and parsimony analyses were predominantly congruent. Subgenus Rhododendron is inferred to be monophyletic, while two of the three sections, Rhododendron and Vireya, are polyphyletic; the monophyly of section Pogonanthum Aitch. & Hemsl. was not tested in this study. Relationships between the species of section Vireya do not correspond to the traditional classification based on morphology, instead correlating strongly with geographic areas, with a disjunction between an Australian–New Guinea clade and clades of west and middle Malesian taxa. The phylogeny also indicates that the ITS region may not undergo complete homogenisation in all species of Rhododendron.

(Hopet 1976), the name R. anagalliJlorum refers to the present new species. Rhododendron xenium is placed in section Vireya subsect. Euvireya ser. Linnaeoidea Sleumer based on scale and corolla features and leaf size. It has the typical Euvire) a scales, sessile, moderately lobed with a small variously colored center, and a corolla that is not salver-shaped; it is placed in series Linnaeoidea because of its small leaves, less than 1 cm by 0.6 cm (Sleumer! 1966). So far this species has only been recorded from Mount Jaya in the Illdonesian province of West Papua (Irian Jaya) on the island of New Guinea. It appears to be most closelv related to R. womersleyi and R. rubineiflorum; however. it differs from these two in numerous characters, outlined in Table 1. The most obvious differing characters are the length of the pedicel and stvle at anthesist and the arrangement of the leaves. Other notable differences between the three species occur in the leaf apex shape and size, corolla shape pedicel indumentum, perulae indumentum. stamen lengthe and staminal filament indumentum (Table 1). The species epithet is derived from the Greek, xenion, gift to a guest, and is in reference to the long pedicel that presents the flower well above the foliage and thus facilitates feeding (and pollination) by nectarivorous birds that are presumed to visit the flowers of this species.

To resolve the relationships of taxa within the Beaufortia suballiance (Myrtaceae), 72 ingroup taxa were analysed by parsimony methods and nrDNA sequence data from the 5S and ITS-1 ribosomal DNA spacer regions. Although basal nodes in the consensus tree (combined data set) are not supported by bootstrap or jackknife values, a number of clades are well supported, showing that Melaleuca is polyphyletic. Monophyletic groups include: endemic species of Melaleuca from New Caledonia (including species of Callistemon recently transferred to Melaleuca); the tropical Melaleuca leucadendra group; Australian species of Callistemon, which relate to species of Melaleuca predominantly from the South-East; and a group of south-western and eastern Australian melaleucas that relate to a clade of three south-western genera, Eremaea, Conothamnus and Phymatocarpus. Calothamnus, Regeliaand Beaufortiamay also relate to this latter group. Lamarchea is possibly related to northern melaleucas. The results have implications for generic revisions of the large genus Melaleuca. Biogeographic subtree analysis, based only on supported nodes of the taxon cladogram, showed New Caledonia, New Guinea, Eastern Queensland and the Northern Desert unresolved at the base of the area cladogram. The position of some of these areas is likely to be artifactual, but New Caledonia is interpreted as in the correct position. At a higher node, the monsoonal northern areas of Australia (Kimberley, Arnhem and Cape York), Atherton, the Pilbara and Western Desert relate to the southern regions, which form a group. The South-West of Australia is related to Eyre and Adelaide (designated area ‘South’) and Tasmania is related to the South-East and MacPherson–Macleay. The vicariance between northern and southern regions in Australia possibly relates to an early major climatic change (from the Early Tertiary). The biogeographic analysis helped illuminate taxon relationships.