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A taxonomic revision of the Pultenaea setulosa species complex (Fabaceae, tribe Mirbelieae) is presented. Prior to this study, P. setulosa Benth. was broadly circumscribed as a single, morphologically variable species. Here, we present evidence supporting the recognition of 18 species, 14 of which are new to science. Pultenaea setulosa is recircumscribed as a morphologically uniform taxon endemic to the Marlborough region in south-east Queensland. We reinstate Pultenaea boormanii H.B.Will., Pultenaea campbellii Maiden & Betche and Pultenaea lapidosa Corrick from synonymy of P. setulosa and describe an additional 14 new species: Pultenaea acanthocalyx R.L.Barrett & Clugston, Pultenaea corrickiae R.L.Barrett, Orme & Clugston, Pultenaea estelleae R.L.Barrett & Clugston, Pultenaea farmeriana R.L.Barrett, Orme & P.H.Weston, Pultenaea hoskingii R.L.Barrett & Clugston, Pultenaea imminuta R.L.Barrett & S.F.McCune, Pultenaea murrayi R.L.Barrett, Pultenaea palssoniae R.L.Barrett & Clugston, Pultenaea praetermissa R.L.Barrett & Albr., Pultenaea purdieae R.L.Barrett & Clugston, Pultenaea renneri R.L.Barrett & Clugston, Pultenaea venusta R.L.Barrett & Orme, Pultenaea westonii R.L.Barrett & Clugston and Pultenaea woolcockiorum R.L.Barrett & Clugston. Sixteen of these species are endemic to New South Wales, one to Queensland and one to Victoria. All taxa are described and illustrated, and habitats and conservation status are discussed. Two additional related species, Pultenaea procumbens A.Cunn. and P. setigera A.Cunn. ex Benth. are recircumscribed. Pultenaea setigera is reinstated here, known from the type collection made in 1822 and is possibly extinct. Lectotypes are selected for the names Pultenaea boormanii, P. campbellii, P. procumbens, P. setigera and P. setulosa. [ABSTRACT FROM AUTHOR]

Premise: Understanding evolutionary history and classifying discrete units of organisms remain overwhelming tasks, and lags in this workload concomitantly impede an accurate documentation of biodiversity and conservation management. Rapid advances and improved accessibility of sensitive high‐throughput sequencing tools are fortunately quickening the resolution of morphological complexes and thereby improving the estimation of species diversity. The recently described and critically endangered Banksia vincentia is morphologically similar to the hairpin banksia complex (B. spinulosa s.l.), a group of eastern Australian flowering shrubs whose continuum of morphological diversity has been responsible for taxonomic controversy and possibly questionable conservation initiatives. Methods: To assist conservation while testing the current taxonomy of this group, we used high‐throughput sequencing to infer a population‐scale evolutionary scenario for a sample set that is comprehensive in its representation of morphological diversity and a 2500‐km distribution. Results: Banksia spinulosa s.l. represents two clades, each with an internal genetic structure shaped through historical separation by biogeographic barriers. This structure conflicts with the existing taxonomy for the group. Corroboration between phylogeny and population statistics aligns with the hypothesis that B. collina, B. neoanglica, and B. vincentia should not be classified as species. Conclusions: The pattern here supports how morphological diversity can be indicative of a locally expressed suite of traits rather than relationship. Oversplitting in the hairpin banksias is atypical since genomic analyses often reveal that species diversity is underestimated. However, we show that erring on overestimation can yield negative consequences, such as the disproportionate prioritization of a geographically anomalous population. [ABSTRACT FROM AUTHOR]

Morphological and single-nucleotide polymorphism data support splitting Pultenaea glabra Benth. into eight species, including one in Victoria, and seven in eastern and northern New South Wales. Six species are newly described, five of which are, like P. glabra , narrow-range endemics within the Greater Blue Mountains World Heritage Area and adjacent sandstone landforms of the Great Dividing Range. The recognition of six new species from what was broadly P. glabra has implications for conservation management, including for P. glabra itself, which has a smaller distribution and more precise habitat requirements than previously thought. One of the new species, P. percussa , is known by a single 1971 gathering only. The occurrence of several narrow-range Blue Mountains endemic Pultenaea species may be explained by the combination of edaphic diversity and topographic complexity, which could act in concert to promote divergences among small, allopatric populations. Hybrids between P. glabra and P. flexilis Sm. are documented for the first time; however, limited evidence for introgression between the two species was observed. The following new taxa are described: Pultenaea aculeata M.A.M.Renner, P.H.Weston & S.Clarke, Pultenaea percussa M.A.M.Renner & P.H.Weston, Pultenaea furcata M.A.M.Renner & R.L.Barrett, Pultenaea mutabilis M.A.M.Renner & P.H.Weston, Pultenaea mutabilis var. angusta M.A.M.Renner, P.H.Weston, & S.Clarke, Pultenaea praecipua M.A.M.Renner & P.H.Weston, Pultenaea praecipua subsp. temperata M.A.M.Renner & R.L.Barrett, and Pultenaea tenebrosa M.A.M.Renner, P.H.Weston & S.Clarke. Lectotypes are designated for Pultenaea villosa var. glabrescens Benth. and Pultenaea weindorferi Reader. The threatened plant Pultenaea glabra is actually a complex of eight species, six of which are new to science. Pultenaea glabra is less common than previously thought, and five of the six new species are also rare and likely threatened, some critically so. This study has significant implications for the conservation of unique flora of the upper Blue Mountains and surrounding country. [ABSTRACT FROM AUTHOR]

Background: Orange jasmine has a complex nomenclatural history and is now known as Murraya paniculata (L.) Jack. Our interest in this common ornamental stemmed from the need to resolve its identity and the identities of closely related taxa as hosts of the pathogen 'Candidatus Liberibacter asiaticus' and its vector Diaphorina citri. Understanding these microbe-vector-plant relationships has been hampered by taxonomic confusion surrounding Murraya at both the generic and specific levels. Results: To resolve the taxonomic uncertainty, six regions of the maternally-inherited chloroplastal genome and part of the nuclear-encoded ITS region were amplified from 85 accessions of Murraya and Merrillia using the polymerase chain reaction (PCR). Clustering used maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference (BI). Chronograms were produced for molecular dating, and to test the monophyly of Murraya rigorously, using selected accessions of Murraya and 26 accessions of the Rutaceae and Simarubaceae. Sequence data from the ITS and chloroplastal regions suggest that Murraya paniculata (sensu (Swingle WT and Reece CR, The Citrus Industry, p. 190–430, 1967)) can be separated into four distinct but morphologically somewhat cryptic taxa: Murraya paniculata (sensu (Mabberley DJ, Taxon 65:366–371, 2016)), M. elongata, M. sumatrana and M. lucida. In addition, Murraya omphalocarpa was identified as a putative hybrid of M. paniculata and M. lucida with two geographically isolated nothovarieties representing reciprocal crosses. Murraya is monophyletic, and molecular dating suggests that it diverged from Merrillia during the Miocene (23–5 Ma) with this Murraya group speciating and dispersing during the Middle Miocene onwards. Conclusions: The accessions from Asia and Australasia used in this study grouped into biogeographical regions that match herbarium specimen records for the taxa that suggest natural allopatric distributions with limited overlap and hybridity. Murraya paniculata has been distributed around the world as an ornamental plant. The division of the Murraya paniculata complex into four species with a rare hybrid also confirms morphological studies. [ABSTRACT FROM AUTHOR]

Proteaceae subfamily Persoonioideae, as presently circumscribed, consists of the monogeneric tribe Placospermeae (Placospermum) and the tribe Persoonieae. The latter comprises the diverse genus Persoonia and monospecific genera found in New Zealand (Toronia), New Caledonia (Garnieria) and south-western Western Australia (Acidonia). Persoonia has 101 species distributed across Australia and has been classified into 11 informal groups. Using data derived from plastid DNA (trnL--trnF region), nuclear rDNA (ITS) and morphological characters, we constructed a phylogeny of Persoonioideae and compared the results to the existing classification. Bayesian and parsimony analyses indicated that Persoonia, as currently defined, is non-monophyletic. The molecular data and combined molecular and morphological data place Toronia in a moderately well supported clade with the monophyletic Rufiflora group of Persoonia from Western Australia. This clade is sister to Acidonia, Garnieria and the remaining Persoonia species. Of the other informal groups in Persoonia, the Teretifolia, Quinquenervis, Laurina, Arborea, Graminea and Chapmaniana groups are supported as monophyletic. The Lanceolata group can be re-circumscribed to be monophyletic by the addition of P. elliptica R.Br. (Longifolia group) and the Dillwynioides group. Relationships within this large, geographically widespread clade are largely unresolved and low DNA-sequence variation within it suggests a recent radiation followed by isolation in south-western and eastern Australia. All endemic Tasmanian Persoonia (Gunnii group taxa) are unresolved at the secondmost basal node of the Persoonieae. Our results suggest that the Rufiflora group should be treated as a new genus and that the infrageneric taxonomy of Persoonia requires minor amendment. [ABSTRACT FROM AUTHOR]

The frequency of evolutionary biome shifts during diversification has important implications for our ability to explain geographic patterns of plant diversity. Recent studies present several examples of biome shifts, but whether frequencies of biome shifts closely reflect geographic proximity or environmental similarity of biomes remains poorly known. We explore this question by using phylogenomic methods to estimate the phylogeny of Hakea, a diverse Australian genus occupying a wide range of biomes. Model-based estimation of ancestral regions indicates that Hakea began diversifying in the Mediterranean biome of southern Australia in the Middle Eocene-Early Oligocene, and dispersed repeatedly into other biomes across the continent. We infer around 47 shifts between biomes. Frequencies of shifts between pairs of biomes are usually similar to those expected from their geographic connectedness or climatic similarity, but in some cases are substantially higher or lower than expected, perhaps reflecting how readily key physiological traits can be modified to adapt lineages to new environments. The history of frequent biome-shifting is reflected in the structure of present-day assemblages, which tend to be more phylogenetically diverse than null-model expectations. The case of Hakea demonstrates that the radiation of large plant clades across wide geographic areas need not be constrained by dispersal limitation or conserved adaptations to particular environments. [ABSTRACT FROM AUTHOR]

Background and Aims The basal eudicot family Proteaceae (approx. 1700 species) shows considerable variation in floral symmetry but has received little attention in studies of evolutionary development at the genetic level. A framework for understanding the shifts in floral symmetry in Proteaceae is provided by reconstructing ancestral states on an upated phylogeny of the family, and homologues of CYCLOIDEA (CYC), a key gene for the control of floral symmetry in both monocots and eudicots, are characterized. Methods Perianth symmetry transitions were reconstructed on a new species-level tree using parsimony and maximum likelihood. CYC-like genes in 35 species (31 genera) of Proteaceae were sequenced and their phylogeny was reconstructed. Shifts in selection pressure following gene duplication were investigated using nested branch-site models of sequence evolution. Expression patterns of CYC homologues were characterized in three species of Grevillea with different types of floral symmetry. Key Results Zygomorphy has evolved 10–18 times independently in Proteaceae from actinomorphic ancestors, with at least four reversals to actinomorphy. A single duplication of CYC-like genes occurred prior to the diversification of Proteaceae, with putative loss or divergence of the ProtCYC1 paralogue in more than half of the species sampled. No shifts in selection pressure were detected in the branches subtending the two ProtCYC paralogues. However, the amino acid sequence preceding the TCP domain is strongly divergent in Grevillea ProtCYC1 compared with other species. ProtCYC genes were expressed in developing flowers of both actinomorphic and zygomorphic Grevillea species, with late asymmetric expression in the perianth of the latter. Conclusion Proteaceae is a remarkable family in terms of the number of transitions in floral symmetry. Furthermore, although CYC-like genes in Grevillea have unusual sequence characteristics, they display patterns of expression that make them good candidates for playing a role in the establishment of floral symmetry. [ABSTRACT FROM AUTHOR]

Species-level relationships within the pantropical, largely rainforest genus Cryptocarya R.Br (Lauraceae) and allied groups have long been problematic. Here, we utilise nuclear RPB2 and plastid trnL–trnF sequence data to reconstruct the phylogenetic relationships among Australian Cryptocarya species. We relate our findings to the previous two disparate attempts to resolve species-level relationships on the basis of traditional taxonomic tools. Our results showed that an early diversification gave rise to two lineages present in Australia and globally. The loss of cataphylls (bract-like leaves in seedlings) seems to be a derived state only found in the larger of these two clades. Ruminate cotyledons is another potentially informative character; however, it is highly likely that this condition arose through convergent or parallel evolution. Little or no molecular variation was observed between many species, which suggests recent diversification. Furthermore, the close relationships between species from two geographically disjunct centres of rainforest diversity within Australia suggests that loss of between-region connectivity is recent. A global revision of the group, incorporating molecular analyses and seedling and fruit morphology, is needed to untangle the complex evolutionary relationships within this genus. [ABSTRACT FROM AUTHOR]

Aim Ecologically driven diversification can create spectacular diversity in both species numbers and form. However, the prediction that the match between intrinsic (e.g. functional trait) and extrinsic (e.g. climatic niche) variables may lead to evolutionary radiation has not been critically tested. Here, we test this hypothesis in the Southern Hemisphere plant family Proteaceae, which shows a spectacular diversity in open mediterranean shrublands in the Southwest Australian Floristic Region (SWAFR) and the Cape Floristic Region (CFR). Species in the Proteaceae family occupy habitats ranging from tropical rain forests to deserts and are remarkably variable in leaf morphology. Location Southern Hemisphere. Methods We built a phylogenetic tree for 337 Proteaceae species (21% of the total), representing all main clades, climatic tolerances and morphologies, and collected leaf functional traits (leaf area, sclerophylly, leaf shape) for 261 species and climatic niche data for 1645 species. Phylogenetic generalized least squares regression and quantitative-trait evolutionary model testing were used to investigate the evolutionary pathways of traits and climatic niches, and their effect on diversification rates. Results We found that divergent selection may have caused lineages in open vegetation types to evolve towards trait and climatic niche optima distinct from those in closed forests. Furthermore, we show that the interaction between open habitats, dry, warm and/or mediterranean climates, and small, sclerophyllous, toothed leaves increases net diversification rates in Proteaceae. Main conclusions Our results suggest that the evolution of specific leaf adaptations may have allowed Proteaceae to adapt to variable climatic niches and diversify extensively in open ecosystems such as those in the CFR and SWAFR. This match between morphology and environment may therefore more generally lead to evolutionary radiation. [ABSTRACT FROM AUTHOR]

Specimens of all known taxa and putative entities belonging to the Banksia spinulosa complex were collected from Kuranda in northern Queensland, western to central Queensland and down the eastern coast of Australia to Wilsons Promontory in southern Victoria. These specimens were used to investigate morphological variation in habit, stems, leaves, inflorescences, fruits and seeds in the complex. Phenetic analysis (unweighted pair-group method with arithmetic mean, UPGMA, clustering and semi-strong hybrid multi-dimensional scaling, SSH–MDS, ordination) was performed on the full dataset of 233 entities using 33 characters (18 quantitative, two binary and 13 multistate). To facilitate visualisation of patterns in both clustering and ordination, we also analysed subgroups based on the results of the phenogram from the full dataset. The results showed that the five known and described taxa are phenetically distinct, viz. B. collina sens. str., B. cunninghamii sens. str., B. neoanglica, B. spinulosa and B. vincentia, and provided support for a further 12 morphometrically diagnosable entities, four of which could not be diagnosed with simple combinations of character states and require further investigation. The present study has highlighted that there is much more hidden morphological diversity in the B. spinulosa complex than has previously been recognised in any of the current competing taxonomies. [ABSTRACT FROM AUTHOR]

Aim We tested whether the divergence of South American and Australian Lomatia was the result of the breakup of Gondwana, and assessed the date of divergence between Tasmania and mainland Australia, and across the Hunter River Valley. Location South America (Chile and Argentina) and eastern Australia (Tasmania, Victoria, New South Wales and Queensland). Methods We sequenced one chloroplast (psbA-trnH intergenic spacer) and two nuclear (PHYA and ITS) markers across all 12 species of Lomatia, five species of Telopea and Embothrium coccineum, and included sequences from Gen- Bank for the rest of the tribe Embothrieae. Species relationships were inferred using Bayesian and maximum likelihood analyses, then divergence times estimated using the random local clock in BEAST. Results The chronogram is congruent with geological events: SAm (SAm (SAm (Tas (NEQld (SEAus north of the Hunter + SEAus south of the Hunter))))). South American and Australian species of Lomatia diverged between 35 and 64 Ma. Tasmanian species of Lomatia diverged from mainland Australian taxa c. 32 Ma. Mainland Australian species of Lomatia are mostly not corroborated as monophyletic but show a divergence either side of the Hunter River Valley, dated at 17 Ma. Main conclusions The divergence date between South American Lomatia ferruginea and Australian species cannot exclude Gondwanan vicariance; however, divergences within South America occurred prior to separation of South America and Australia from Antarctica. Tasmanian species diverged from mainland Australia in the early Oligocene. Mainland Australian species of Lomatia are not resolved but form two clades representing populations north and south of the Hunter River Valley, confirming the Hunter River Valley as a significant barrier to gene flow for plants. We suggest that drying events that divided northern and southern floras at the Hunter River Valley occurred at the same time as those that divided eastern and western floras. [ABSTRACT FROM AUTHOR]

PREMISE OF THE STUDY: Subtribe Hakeinae (526 spp.) represents a large Australian plant radiation central to our understanding of that flora's evolution and ecology. It contains Grevillea--the third largest plant genus in Australia and a group inferred to have among the highest diversification rates in the angiosperms. However, we lack a robust phylogenetic framework for understanding subtribe Hakeinae and recognize that Grevillea lacks an unambiguous synapomorphy supporting its monophyly. METHODS: We used four plastid and one nuclear DNA region from a taxonomically even sampling of a third of the species to infer a time-calibrated phylogeny of Hakeinae and absolute diversification rates of major clades. We developed the R package addTaxa to add unsampled taxa to the tree for diversification rate inference. KEY RESULTS: Grevillea is paraphyletic with respect to Hakea and Finschia. Under most parameter combinations, Hakea contains the major clade with the highest diversification rate in Hakeinae, rather than Grevillea. The crown age of the Grevillea+Hakea+Finschia crown group is about double that of prior estimates. CONCLUSIONS: We demonstrate that the paraphyly of Grevillea considerably enlarges the number of Australian descendants from its most recent common ancestor but has also misled investigators who considered a single operational taxonomic unit as adequate to represent the genus for inferences of diversification rate and timing. Our time-calibrated phylogeny can form the basis of future evolutionary, comparative ecology, and biogeography studies involving this large Australian plant radiation, as well as nomenclatural changes. [ABSTRACT FROM AUTHOR]

Premise of study: Have Gondwanan rainforest floral associations survived? Where do they occur today? Have they survived continuously in particular locations? How significant is their living floristic signal? We revisit these classic questions in light of significant recent increases in relevant paleobotanical data. • Methods: We traced the extinction and persistence of lineages and associations through the past across four now separated regions-Australia, New Zealand, Patagonia, and Antarctica-using fossil occurrence data from 63 well-dated Gondwanan rainforest sites and 396 constituent taxa. Fossil sites were allocated tofour age groups: Cretaceous, Paleocene-Eocene, Neo-gene plus Oligocene, and Pleistocene. We compared the modern and ancient distributions of lineages represented in the fossil record to see if dissimilarity increased with time. We quantified similarity-dissimilarity of composition and taxonomic structure among fossil assemblages, and between fossil and modern assemblages. • Key results: Strong similarities between ancient Patagonia and Australia confirmed shared Gondwanan rainforest history, but more of the lineages persisted in Australia. Samples of ancient Australia grouped with the extant floras of Australia, New Guinea, New Caledonia, Fiji, and Mt. Kinabalu. Decreasing similarity through time among the regional floras of Antarctica, Patagonia, New Zealand, and southern Australia reflects multiple extinction events. • Conclusions: Gondwanan rainforest lineages contribute significantly to modern rainforest community assembly and often co-occur in widely separated assemblages far from their early fossil records. Understanding how and where lineages from ancient Gondwanan assemblages co-occur today has implications for the conservation of global rainforest vegetation, including in the Old World tropics. [ABSTRACT FROM AUTHOR]

Aim Our aim was to implement a molecular dating analysis and assess divergence times among taxa of Winteraceae. This enabled us to test hypotheses of vicariance versus long-distance dispersal to explain intercontinental disjunctions in the family. Location Madagascar, Australia (including Lord Howe Island), New Zealand, New Caledonia and South America. Methods We sampled all Australian species and subspecies of Winteraceae. We also included the monotypic Takhtajania perrieri and at least two species of each genus from New Zealand, New Caledonia and South America. Three sets of sequences were combined into one data matrix, including two internal transcribed spacer ( ITS) data sets and a trnL-F data set. Both ITS data sets included all genera of Winteraceae, and the paralogous genes identified in Zygogynum s.l. in a previous study were sequenced and aligned in separate ITS data sets. A Bayesian molecular phylogenetic tree of extant Winteraceae was used as a backbone constraint in paup* to establish the placement of fossils. Bayesian analyses were performed using beast, implementing fossil priors to fit lognormal distributions, to test a maximum-parsimony phylogeny and assess divergence times. Results Interspecific relationships generally agreed with previous analyses. In particular, Bubbia comptonii was found to be sister to the rest of the Bubbia/ Zygogynum clade, but our analysis has uniquely found sister clades within this group: one from New Caledonia, and one from Australia including Lord Howe Island. The phylogeny yields an age of 91.2 Ma with a 95% confidence interval of 118-67 Ma for crown-group Winteraceae. Main conclusions The estimated age of Takhtajania is consistent with its origin in Madagascar as a result of Gondwanan vicariance - the only angiosperm for which this has been demonstrated with confidence. Differentiation of the rest of this ancient clade is a complicated story of vicariance as a result of the rifting, submergence and exhumation of continents and of long-distance dispersal and extinctions. [ABSTRACT FROM AUTHOR]

Background and Aims When species cohesion is maintained despite ongoing natural hybridization, many questions are raised about the evolutionary processes operating in the species complex. This study examined the extensive natural hybridization between the Australian native shrubs Lomatia myricoides and L. silaifolia (Proteaceae). These species exhibit striking differences in morphology and ecological preferences, exceeding those found in most studies of hybridization to date. Methods Nuclear microsatellite markers (nSSRs), genotyping methods and morphometric analyses were used to uncover patterns of hybridization and the role of gene flow in morphological differentiation between sympatric species. Key Results The complexity of hybridization patterns differed markedly between sites, however, signals of introgression were present at all sites. One site provided evidence of a large hybrid swarm and the likely presence of multiple hybrid generations and backcrosses, another site a handful of early generational hybrids and a third site only traces of admixture from a past hybridization event. The presence of cryptic hybrids and a pattern of morphological bimodality amongst hybrids often disguised the extent of underlying genetic admixture. Conclusions Distinct parental habitats and phenotypes are expected to form barriers that contribute to the rapid reversion of hybrid populations to their parental character state, due to limited opportunities for hybrid/intermediate advantage. Furthermore, strong genomic filters may facilitate continued gene flow between species without the danger of assimilation. Stochastic fire events facilitate temporal phenological isolation between species and may partly explain the bi-directional and site-specific patterns of hybridization observed. Furthermore, the findings suggest that F1 hybrids are rare, and backcrosses may occur rapidly following these initial hybridization events. [ABSTRACT FROM PUBLISHER]

* Premise of study: The mechanisms by which plants tolerate water deficit are only just becoming clear. One key factor in drought tolerance is the ability to maintain the capacity to conduct water through the leaves in conditions of water stress. Recent work has shown that a simple feature of the leaf xylem cells, the cube of the thickness of cell walls divided by the lumen width (t/b)³, is strongly correlated with this ability. * Methods: Using ecologically, phylogenetically, and anatomically diverse members of Proteaceae, we tested the relationships between (t/b)³ and climate, leaf mass per unit area, leaf area, and vein density. To test relationships at high phylogenetic levels (mostly genus), we used phylogenetic and nonphylogenetic single and multiple regressions based on data from 50 species. We also used 14 within-genus species pairs to test for relationships at lower phylogenetic levels. * Key results: All analyses revealed that climate, especially mean annual precipitation, was the best predictor of (t/b)³. The variation in (t/b)³ was driven by variation in both lumen diameter and wall thickness, implying active control of these dimensions. Total vein density was weakly related to (t/b)³ but unrelated to either leaf area or climate. * Conclusions: We conclude that xylem reinforcement is a fundamental adaptation for water stress tolerance and, among evergreen woody plants, drives a strong association between rainfall and xylem anatomy. The strong association between (t/b)³ and climate cannot be explained by autocorrelation with other aspects of leaf form and anatomy that vary along precipitation gradients. [ABSTRACT FROM AUTHOR]

Lomatia R.Br. is a genus of 12 species in South America and eastern Australia. Hybridisation is extensive in the Australian species and molecular work is required to understand phylogenetic relationships and examine potential gene flow among species. We developed a library of microsatellite markers for Lomatia silaifolia (Sm.) R.Br. These markers were tested across population samples of L. silaifolia and L. myricoides (C.F.Gaertn.) Domin, assessed for cross amplification across all 12 species of Lomatia, sequenced and inspected for variation in the microsatellite flanking region (MFR), and utilised for phylogeographic and phylogenetic analysis. Nineteen microsatellite markers were tested, 13 of which were polymorphic in size analysis. Four of the markers amplified consistently within Lomatia and the MFR had equivalent to or more sequence variation than the three universal markers (psbA-trnH intergenic spacer, PHYA, ITS). Variation within five individuals of L. silaifolia indicated that MFR could be phylogeographically informative. Combined phylogenetic analysis of Lomatia using universal markers andMFRresulted in a well supported tree; however, phylogenetic analysis of only MFR suggested non-monophyly of the species. Phylogenetic trees supported South American species as being diverged from the Australian species but paraphyletic with respect to the Australian lineage. Relationships among Australian species of Lomatia are correlated with geography rather than morphology. We found that microsatellite markers designed for Lomatia and the flanking regions can be informative at population, phylogenetic and phylogeographic levels. [ABSTRACT FROM AUTHOR]

* Premise of the study: The glacial cycles of the Quaternary did not impact Australia in the same way as Europe and North America. Here we investigate the history of population isolation, species differentiation, and hybridization in the southeastern Australian landscape, using five species of Lomatia (Proteaceae). We use a chloroplast DNA phylogeography to assess chloroplast haplotype (chlorotype) sharing among these species and whether species with shared distributions have been affected by shared biogeographic barriers. * Methods: We used six chloroplast DNA simple sequence repeats (cpSSR) across five species of Lomatia, sampled across their entire distributional range in southeastern Australia. Resulting size data were combined, presented as a network, and visualized on a map. Biogeographical barriers were tested using AMOVA. To explore hypotheses of chlorotype origin, we converted the network into a cladogram and reconciled with all possible species trees using parsimony-based tree mapping. * Key results: Some chlorotypes were shared across multiple species of Lomatia in the study, including between morphologically differentiated species. Chlorotypes were either widespread in distribution or geographically restricted to specific regions. Biogeographical structure was identified across the range of Lomatia. The most parsimonious reconciled tree incorporated horizontal transfer of chlorotypes. * Conclusions: Lomatia shows evidence of both incomplete lineage sorting and extensive hybridization between co-occurring species. Although the species in the study appear to have responded to a number of biogeographic barriers to varying degrees, our findings identified the Hunter River Valley as the most important long-term biogeographic barrier for the genus in south eastern Australia. [ABSTRACT FROM AUTHOR]

Taxa in the Banksia spinulosa Sm. complex (Proteaceae) have populations with sympatric, parapatric and allopatric distributions and unclear or disputed boundaries. Our hypothesis is that under biological, phenetic and diagnosable species concepts that each of the currently named taxa within the B. spinulosa complex is a separate species. Based on specimens collected as part of this study, and data recorded from specimens in six Australian herbaria, complemented by phenetic analysis (semi--strong multidimensional scaling and UPGMA clustering) and a detailed morphological study, we investigated both morphological variation and geographic distribution in the B. spinulosa complex. All specimens used for this study are held at the N.C.W. Beadle Herbarium or the National Herbarium of New South Wales. In total 23 morphological characters (11 quantitative, five binary, and seven multistate characters) were analysed phenetically for 89 specimens. Ordination and cluster analysis resulted in individuals grouping strongly allowing recognition of distinct groups consistent with their recognition as separate species. Additional morphological analysis was completed on all specimens using leaf, floral, fruit and stem morphology, providing clear cut diagnosable groups and strong support for the recognition of B. spinulosa var. cunninghamii and B. spinulosa var. neoanglica as species. [ABSTRACT FROM AUTHOR]

* Premise of the study: A past study based on morphological data alone showed that the means by which plants of the Australian genus Hakea reduce florivory is related to the evolution of bird pollination. For example, bird pollination was shown to have arisen only in insect-pollinated lineages that already produced greater amounts of floral cyanide, a feature that reduces florivory. We examine a central conclusion of that study, and a common assumption in the literature, that bird pollination arose in insect-pollinated lineages, rather than the reverse. * Methods: We combined morphological and DNA data to infer the phylogeny and age of the Australian genus Hakea, using 9.2 kilobases of plastid and nuclear DNA and 46 morphological characters from a taxonomically even sampling of 55 of the 149 species. * Key results : Hakea is rooted confidently in a position that has not been suggested before. The phylogeny implies that bird pollination is primitive in Hakea and that multiple shifts to insect pollination have occurred. The unexpectedly young age of Hakea (a crown age of ca. 10 Ma) makes it coincident with its primary bird pollinators (honeyeaters) throughout its history. * Conclusions: Our study demonstrates that Hakea is an exception to the more commonly described shift from insect to bird pollination. However, we note that only one previous phylogenetic study involved Australian plants and their honeyeater pollinators and that our finding might prove to be more common on that continent. [ABSTRACT FROM AUTHOR]

Background: Four of the five species of Telopea (Proteaceae) are distributed in a latitudinal replacement pattern on the south-eastern Australian mainland. In similar circumstances, a simple allopatric speciation model that identifies the origins of genetic isolation within temporal geographic separation is considered as the default model. However, secondary contact between differentiated lineages can result in similar distributional patterns to those arising from a process of parapatric speciation (where gene flow between lineages remains uninterrupted during differentiation). Our aim was to use the characteristic distributional patterns in Telopea to test whether it reflected the evolutionary models of allopatric or parapatric speciation. Using a combination of genetic evidence and environmental niche modelling, we focused on three main questions: do currently described geographic borders coincide with genetic and environmental boundaries; are there hybrid zones in areas of secondary contact between closely related species; did species distributions contract during the last glacial maximum resulting in distributional gaps even where overlap and hybridisation currently occur? Results: Total genomic DNA was extracted from 619 individuals sampled from 36 populations representing the four species. Seven nuclear microsatellites (nSSR) and six chloroplast microsatellites (cpSSR) were amplified across all populations. Genetic structure and the signature of admixture in overlap zones was described using the Bayesian clustering methods implemented in STUCTURE and NewHybrids respectively. Relationships between chlorotypes were reconstructed as a median-joining network. Environmental niche models were produced for all species using environmental parameters from both the present day and the last glacial maximum (LGM). The nSSR loci amplified a total of 154 alleles, while data for the cpSSR loci produced a network of six chlorotypes. STRUCTURE revealed an optimum number of five clusters corresponding to the four recognised species with the additional division of T. speciosissima into populations north and south of the Shoalhaven River valley. Unexpectedly, the northern disjunct population of T. oreades grouped with T. mongaensis and was identified as a hybrid swarm by the Bayesian assignment test implemented in NewHybrids. Present day and LGM environmental niche models differed dramatically, suggesting that distributions of all species had repeatedly expanded and contracted in response to Pleistocene climatic oscillations and confirming strongly marked historical distributional gaps among taxes.Conclusions: Genetic structure and bio-climatic modeling results are more consistent with a history of allopatric speciation followed by repeated episodes of secondary contact and localised hybridisation, rather than with parapatric speciation. This study on Telopea shows that the evidence for temporal exclusion of gene flow can be found even outside obvious geographical contexts, and that it is possible to make significant progress towards excluding parapatric speciation as a contributing evolutionary process. [ABSTRACT FROM AUTHOR]

Aim The mesic biome, encompassing both rain forest and open sclerophyllous forests, is central to understanding the evolution of Australia's terrestrial biota and has long been considered the ancestral biome of the continent. Our aims are to review and refine key hypotheses derived from palaeoclimatic data and the fossil record that are critical to understanding the evolution of the Australian mesic biota. We examine predictions arising from these hypotheses using available molecular phylogenetic and phylogeographical data. In doing so, we increase understanding of the mesic biota and highlight data deficiencies and fruitful areas for future research. Location The mesic biome of Australia, along the eastern coast of Australia, and in the south-east and south-west, including its rain forest and sclerophyllous, often eucalypt-dominated, habitats. Methods We derived five hypotheses based on palaeoclimatic and fossil data regarding the evolution of the Australian mesic biota, particularly as it relates to the mesic biome. We evaluated predictions formulated from these hypotheses using suitable molecular phylogenies of terrestrial plants and animals and freshwater invertebrates. Results There was support for the ancestral position of mesic habitat in most clades, with support for rain forest habitat ancestry in some groups, while evidence of ancestry in mesic sclerophyllous habitats was also demonstrated for some plants and herpetofauna. Contraction of mesic habitats has led to extinction of numerous lineages in many clades and this is particularly evident in the rain forest component. Species richness was generally higher in sclerophyllous clades than in rain forest clades, probably due to higher rates of net speciation in the former and extinction in the latter. Although extinction has been prominent in rain forest communities, tropical rain forests appear to have experienced extensive immigration from northern neighbours. Pleistocene climatic oscillations have left genetic signatures at multiple levels of divergence and with complex geographical structuring, even in areas with low topographical relief and few obvious geographical barriers. Main conclusions Our review confirms long-held views of the ancestral position of the Australian mesic biome but also reveals new insights into the complexity of the processes of contraction, fragmentation, extinction and invasion during the evolution of this biome. [ABSTRACT FROM AUTHOR]

Background: Inter-population distance and differences in breeding times are barriers to reproduction that can contribute to genotypic differentiation between populations. Temporal changes in environmental conditions and local selective processes can further contribute to the establishment of reproductive barriers. Telopea speciosissima (Proteaceae) is an excellent subject for studying the effect of geographic, edaphic and phenological heterogeneity on genotypic differentiation because previous studies show that these factors are correlated with morphological variation. Molecular, morphological and environmental datasets were combined to characterise the relative influence of these factors on inter-population differentiation, and Bayesian analyses were used to investigate current levels of admixture between differentiated genomes. Results: A landscape genetic approach involving molecular and morphological analyses identified three endpoints of differentiated population groups: coastal, upland and southern. The southern populations, isolated from the other populations by an edaphic barrier, show low migration and no evidence of admixture with other populations. Amongst the northern populations, coastal and upland populations are connected along a skewed altitudinal gradient by genetically intermediate populations. The strong association between temperature and flowering time in Telopea speciosissima was shown to maintain a temporally unstable reproductive barrier between coastal and upland populations. Conclusions: Substrate-mediated allopatry appears to be responsible for long-term genetic isolation of the southern populations. However, the temperature-dependent reproductive barrier between upland and coastal populations bears the genetic signature of temporal adjustments. The extreme climatic events of the last glacial maximum are likely to have caused more complete allochronic isolation between upland and coastal populations, as well as exerting increased selective pressure upon local genomes. However, at intermediate altitudes, current climatic conditions allow for the incorporation of alleles from previously distinct genomes, generating new, intermediate genomic assemblages and possibly increasing overall adaptive potential. [ABSTRACT FROM AUTHOR]

Dating the Tree of Life has now become central to relating patterns of biodiversity to key processes in Earth history such as plate tectonics and climate change. Regions with a Mediterranean climate have long been noted for their exceptional species richness and high endemism. How and when these biota assembled can only be answered with a good understanding of the sequence of divergence times for each of their components. A critical aspect of dating by using molecular sequence divergence is the incorporation of multiple suitable age constraints. Here, we show that only rigorous phylogenetic analysis of fossil taxa can lead to solid calibration and, in turn; stable age estimates, regardless of which of 3 relaxed clock-dating methods is used. We find that Proteaceae, a model plant group for the Mediterranean hotspots of the Southern Hemisphere with a very rich pollen fossil record, diversified under higher rates in the Cape Floristic Region and Southwest Australia than in any other area of their total distribution. Our results highlight key differences between Mediterranean hotspots and indicate that Southwest Australian biota are the most phylogenetically diverse but include numerous lineages with low diversification rates. [ABSTRACT FROM AUTHOR]

Calycanthaceae, sister to all other Laurales, are the most distinct family of the order in their gynoeciumstructure (lateral placentation, presence of two ovules). Gynoeciumstructure was studied in a representative of each genus of Calycanthaceae and gynoecium development in a representative of each of the two subfamilies (Calycanthoideae andIdiospermoideae).Newly foundshared features are postgenital coherence between the free carpels (extragynoecial compitum), abortion of the upper of the two ovules, and lobation of the outer integument.Differences in reproductive structures between the two subfamilies are reviewed. Newly found differences include carpel primordium shape, contribution of the outer integument tomicropyle formation, epidermis differentiation of the rim of the integuments, and mode of formation of the compitum. Unexpectedly, at anthesis, ovary and ovules of Idiospermum are not larger than those ofCalycanthoideae, despite the conspicuous difference in fruit. The identity of ''staminodes'' (sterile organs between stamens and carpels) is discussed. Sterile carpel-like structures (carpellodes) are documented in Idiospermum. The lateral ovule position in Calycanthaceae is correlatedwith a different development of carpel closure as compared with core Laurales, which exhibit median ovule position. Gynoecium morphology of fossil Calycanthaceae and its implications for gynoecium evolution in Calycanthaceae and Laurales are discussed. [ABSTRACT FROM AUTHOR]

Tribe Macadamieae (91 spp., 16 genera; Proteaceae) is widespread across the southern hemisphere on all major fragments of Gondwana except New Zealand and India. Macadamia is cultivated outside its natural range as a "nut" crop (notably in Hawaii, where it is the principal orchard crop). We sampled seven DNA regions and 53 morphological characters from the tribe to infer its phylogeny and address the common assumption that the distribution of the extant diversity of the tribe arose by the rafting of ancestors on Gondwanan fragments. Macadamia proves to be paraphyletic with respect to the African genus Brabejum, the South American genus Panopsis, and the Australian species Orites megacarpus. We erect two new generic names, Nothorites and Lasjia, to produce monophyly at that rank. The earliest disjunctions in the tribe are inferred to be the result of long-distance dispersal out of Australia (with one possible exception), rather than vicariance. Evolution of tardy fruit dehiscence is correlated with these dispersals, and the onset of the Antarctic Circumpolar Current (ACC) precedes them. We suggest that the ancestors of extant diversity arrived on their respective continents via the ACC, and we recognize that this is a mechanism precluded, rather than facilitated,by Gondwana's terrestrial continuity. [ABSTRACT FROM AUTHOR]

Sunken, covered, and encrypted stomata have been anecdotally linked with dry climates and reduced transpiration and therefore have been used to infer dry palaeoclimates from fossils. This study assesses the evolutionary and ecological associations of such stomatal protection in a model system-the diverse southern hemisphere family Proteaceae. Analyses were based on the morphology of over 1400 Australian, South African, New Caledonian, New Zealand, and South American species, anatomy of over 300 of these species, and bioclimatic data from all 1109 Australian species. Ancestral state reconstruction revealed that five or six evolutionary transitions explain over 98% of the dry climate species in the family, with a few other, minor invasions of dry climates. Deep encryption, i.e., stomata in deep pits, in grooves, enclosed by tightly revolute margins or strongly overarched by cuticle, evolved at least II times in very dry environments. Other forms of stomatal protection (sunken but not closely encrypted stomata, papi!lae, and layers of hairs covering the stomata) also evolved repeatedly, but had no systematic association with dry climates. These data are evidence for a strong distinction in function, with deep encryption being an adaptation to aridity, whereas broad pits and covered stomata have more complex relations to climate. [ABSTRACT FROM AUTHOR]

Aim The flowering plant family Proteaceae is putatively of Gondwanan age, with modern and fossil lineages found on all southern continents. Here we test whether the present distribution of Proteaceae can be explained by vicariance caused by the break-up of Gondwana. Location Africa, especially southern Africa, Australia, New Zealand, South America, New Caledonia, New Guinea, Southeast Asia, Sulawesi, Tasmania. Methods We obtained chloroplast DNA sequence data from the rbcL gene, the rbcL- atpB spacer, and the atpB gene from leaf samples of forty-five genera collected from the field and from living collections. We analysed these data using Bayesian phylogenetic and molecular dating methods, with five carefully selected fossil calibration points to obtain age estimates for the nodes within the family. Results Four of eight trans-continental disjunctions of sister groups within our sample of the Proteaceae post-date the break-up of Gondwana. These involve independent lineages, two with an Africa-Australia disjunction, one with an Africa–South America disjunction, and one with a New Zealand–Australasia disjunction. The date of the radiation of the bird-pollinated Embothriinae corresponds approximately to the hypothesized date of origin of nectar-feeding birds in Australia. Main conclusions The findings suggest that disjunct distributions in Proteaceae result from both Gondwanan vicariance and transoceanic dispersal. Our results imply that ancestors of some taxa dispersed across oceans rather than rafting with Gondwanan fragments as previously thought. This finding agrees with other studies of Gondwanan plants in dating the divergence of Australian, New Zealand and New Caledonian taxa in the Eocene, consistent with the existence of a shared, ancestral Eocene flora but contrary to a vicariance scenario based on accepted geological knowledge. [ABSTRACT FROM AUTHOR]

Calycanthaceae are sister to the remainder of Laurales (magnoliid clade), an order seemingly showing high variability in floral phyllotaxis. Previous studies of floral phyllotaxis in this family focused on one species, Calycanthus floridus. Therefore, a comparative study of floral phyllotaxis, comprising species of all four genera of the family, was undertaken. Floral phyllotaxis is spiral according to the Fibonacci pattern for all species studied. The more or less extensive transition zone from the vegetative decussate to the floral spiral phyllotaxis comprises three to 19 organs. There is usually a gradual transition between floral organ types, especially between different functional parts of the perianth and between stamens, staminodes, and carpels. The transition between staminodes and carpels sometimes shows irregularities in organ sequence along the ontogenetic spiral. There is a tendency to form series of organs of the same kind in Fibonacci numbers. Thecae dehisce via laterally hinged valves in Sinocalycanthus but via simple longitudinal slits in all other genera. Food bodies are present on the stamens and inner tepals of Calycanthus and Sinocalycanthus but differ in extent. All previously described calycanthaceous fossil flowers (Araripia, Virginianthus, Jerseyanthus) appear to show spiral floral phyllotaxis. In the three-dimensionally preserved Virginianthus and Jerseyanthus, arrangement of androecium organs in series of Fibonacci numbers appears to be present. [ABSTRACT FROM AUTHOR]

The thynnine wasp genus Neozeleboria Rohwer is the main pollinating group of the sexually deceptive Australian orchid genus, Chiloglottis R.Br. In a highly specialized interaction, Chiloglottis species attract males from a single or very few Neozeleboria species through the chemical mimicry of the female wasp's sex pheromone. An earlier study examining the historical association among Chiloglottis and Neozeleboria using DNA sequence data found matching phylogenetic patterns suggestive of cospeciation between orchids and pollinators. However, patterns of constraint in Neozeleboria emergence phenology and sex pheromones suggested that the close association among orchid and wasp clades may be due to pollinator switching among closely related wasp taxa that have similar traits. In this study, we further examine the association by incorporating a morphological phylogenetic analysis of non-pollinating as well as pollinating Neozeleboria. The morphological analysis is then compared with DNA sequence data from one nuclear and one mitochondrial gene for an increased sample of outgroup genera. The combined molecular data set finds a monophyletic Neozeleboria, although support for this was not strong in the individual data sets. A high congruence between molecular and morphological analyses was found among higher groupings of Neozeleboria. Neozeleboria species that pollinate Chiloglottis species are not found as a monophyletic group but, rather, are scattered throughout a phylogeny comprising pollinators and non-pollinators. Under the cospeciation model, the presence of related Neozeleboria non-pollinators carries the unlikely implication that the association between plant and pollinator has been repeatedly lost. Instead, we favour the alternative ‘preferential pollinator switching’ model that accounts for the specialization among orchid and wasp lineages in terms of similarities in traits among related Neozeleboria. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society, 2005, 86, 381–395. [ABSTRACT FROM AUTHOR]

Species of the major Southern Hemisphere family, Proteaceae, have many scleromorphic anatomical structures in their leaves. Many of these structures (very thick cuticles and five anatomically distinct structures beneath the epidermis) are associated with the leaf surface exposed to direct light. These structures increase the path through which solar radiation must pass before reaching the mesophyll. In this study, such structures are proposed to protect the mesophyll from excess solar radiation, including photosynthetically active, ultraviolet, and possibly infrared radiation. Scleromorphic structures of the upper leaf surface and nonscleromorphic photoprotective structures (dense trichomes and papillae of the upper surface) occur almost exclusively in open vegetation. Open vegetation species of Proteaceae occur in oligotrophic and/or cold and/or dry places, where protection from light in excess of photosynthetic capacity and damage from ultraviolet light should be most important. Data from 123 species and a supertree constructed from available molecular phylogenies are used to show that the proposed photoprotective structures evolved many times within Proteaceae. In tests of correlated evolution, the proposed photoprotective structures are significantly associated with open vegetation, but not with dry habitats. [ABSTRACT FROM AUTHOR]

Investigates the extent of pollinator conservatism and how it may be maintained by reconstructing both orchid and pollinator relationships among a genus species pollinated by thynnine wasps. Principles of pollinator attraction in Chiloglottis species and related genus Arthrochilus; Discussion on whether there are patterns of phylogenetic congruence between the species and their wasp pollinators.

Presents a study that used DNA sequence data from plastid matK and trnL-F regions in phylogenetic analyses of Diurideae. Background on Diurideae, a southern Hemisphere species of terrestrial orchids; Methodology; Results and discussion.

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]

How and why organisms are distributed as they are has long intrigued evolutionary biologists. The tendency for species to retain their ancestral ecology has been demonstrated in distributions on local and regional scales, but the extent of ecological conservatism over tens of millions of years and across continents has not been assessed. Here we show that biome stasis at speciation has outweighed biome shifts by a ratio of more than 25:1, by inferring ancestral biomes for an ecologically diverse sample of more than 11,000 plant species from around the Southern Hemisphere. Stasis was also prevalent in transocean colonizations. Availability of a suitable biome could have substantially influenced which lineages establish on more than one landmass, in addition to the influence of the rarity of the dispersal events themselves. Conversely, the taxonomic composition of biomes has probably been strongly influenced by the rarity of species’ transitions between biomes. This study has implications for the future because if clades have inherently limited capacity to shift biomes, then their evolutionary potential could be strongly compromised by biome contraction as climate changes. [ABSTRACT FROM AUTHOR]