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Purpose Endemic to Noongar Country of southwestern Australia, the charismatic and much-loved mistletoe, Nuytsia floribunda (Labill.) R.Br. ex G.Don (Munjee/Moodjar in Noongar language), was the subject of a 2010 review which explored aspects of its cultural importance and botanical attributes based largely on early colonial accounts and scientific findings. Our purpose was to apply cross-cultural methods to review and update findings reported by Hopper (2010). Methods We have recently explored this iconic species through a collaborative Elder-led, cross-cultural process, largely through oral accounts of contemporary Merningar Noongar knowledge holders. Results We record previously unpublished insights relating to Nuytsia floribunda, and longheld Noongar custom relating to its conservation, use and multi-faceted relationships with southwestern Australia’s First Nations peoples. We present Noongar- and Western science-derived knowledge relating to the physiology, ecology and evolution of this species. Conclusion The unique biology, ingenuity and physical prominence of Nuytsia floribunda has been recognised in Noongar lore for millennia. We suggest it as a valuable teacher and exemplar of prosperous survival in old, climatically-buffered, infertile landscapes and to this end, should be widely celebrated.

Aims and background Underground storage organs (USOs) have long featured prominently in human diets. They are reliable year-round resources, especially valuable in seasonal climates. We review a significant but scattered literature and oral recounts of USOs utilised by Noongar people of the Southwest Australian Floristic Region (SWAFR). USOs are important to First Nations cultures in other geophyte-rich regions with Mediterranean climate, with specialist knowledge employed, and productive parts of the landscape targeted for harvest, with likely ecological interactions and consequences. Methods We have gathered Noongar knowledge of USOs in the SWAFR to better understand the ecological role of Noongar-USO relationships that have existed for millennia. Results We estimate that 418 USO taxa across 25 families have Noongar names and/or uses. Additionally, three USO taxa in the SWAFR weed flora are consumed by Noongar people. We found parallels in employment of specific knowledge and targeted ecological disturbance with First Nations’ practice in other geophyte-rich floristic regions. We found that only in 20% of cases could we identify the original source of recorded USO knowledge to an acknowledged Noongar person. Conclusion This review identified that traditional Noongar access to USOs is taxonomically and geographically extensive, employing specific knowledge and technology to target and maintain resource rich locations. However, we also found a general practice of ‘extractive’ documentation of Noongar plant knowledge. We identify negative implications of such practice for Noongar people and SWAFR conservation outcomes and assert ways to avoid this going forward, reviving Noongar agency to care for traditional Country.

Landscape-level processes such as fire regimes, increasing disease prevalence and a drying climate are emerging threats affecting plant groups such as the Proteaceae. Using field derived empirical data and a population simulation model we investigated population-level impacts of canker diseases and contemporary fire regimes on the threatened shrub and granite outcrop endemic Banksia verticillata R.Br. We found the persistence of B. verticillata on granite inselbergs is strongly influenced by fire frequency and extent, as well as the prevalence of canker disease. For populations where canker is present but having a relatively lower impact none of the fire scenarios resulted in extinction over the 100-year simulation, but all scenarios resulted in population decline with the magnitude of the effect increasing with fire frequency and extent (proportion of plants killed). In contrast, higher impact canker disease scenarios resulted in rapid population declines and potential extinction. Small increases in inter-fire adult survival reduced the rate of decline in populations with relatively low canker infestation. Research is urgently needed to understand the role that a warming and drying climate in the South-west Australian Floristic Region may have on the epidemiology of canker disease and the feasibility and effectiveness of treating individuals with appropriate fungicides.

Plant species richness increases with declining soil phosphorus (P) availability, especially for Proteaceae in old infertile landscapes. This difference in richness might be attributed to faster diversification in lineages adapted to P-impoverished soils, i.e. species that possess specialised P-acquisition strategies, and have lower leaf P concentration ([P]) and higher seed [P]. Alternatively, a longer time for species accumulation might contribute to high species richness in low-P environments due to the geological stability of the landscapes in which they evolved. We assessed differences in diversification of Proteaceae in P-impoverished vs. nutrient-rich environments and whether these were linked to adaptations to P-impoverished soils. We explored mature leaf and seed [P] and investigated how these traits changed over the evolutionary history of the family, and within two species-rich genera (Banksia, Hakea). Faster diversification was correlated with lower leaf and higher seed [P] for species-rich genera across the Proteaceae. For Banksia and Hakea, diversification rates peaked at relatively low leaf [P], but not at the lowest leaf [P]. Ancestral state reconstructions indicated that low leaf [P] is a trait that was likely present in the early evolution of the Proteaceae, with recent transitions to higher leaf [P] across several species-poor rainforest genera. Diversification of Proteaceae correlated strongly with P-related traits. In an evolutionary context, functional cluster roots, low leaf [P] and high seed [P] were likely key innovations allowing diversification. Selection for low leaf [P] early in the evolutionary history of Proteaceae pre-adapted ancestors of this family to diversify into oligotrophic environments. We discuss how our findings are likely relevant for understanding diversification dynamics of other plant families that occur in P-impoverished environments.

Background and Aims In plants, the spatial and genetic distance between mates can influence reproductive success and offspring fitness. Negative fitness consequences associated with the extremes of inbreeding and outbreeding suggest that there will be an intermediate optimal outcrossing distance (OOD), the scale and drivers of which remain poorly understood. In the bird-pollinated Anigozanthos manglesii (Haemodoraceae) we tested (1) for the presence of within-population OOD, (2) over what scale it occurs, and (3) for OOD under biologically realistic scenarios of multi-donor deposition associated with pollination by nectar-feeding birds. Methods We measured the impact of mate distance (spatial and genetic) on seed set, fruit size, seed mass, seed viability and germination success following hand pollination from (1) single donors across 0 m (self), Key results Inter-mate distance had a significant impact on single-donor reproductive success, with selfed and nearest-neighbour ( Conclusions Collectively, single- and multi-donor pollinations indicated evidence for a near-neighbour OOD within A. manglesii. A survey of the literature suggests that within-population OOD may be more characteristic of plants pollinated by birds than those pollinated by insects.

Background and AimsHybridization is an important evolutionary process that can have a significant impact on natural plant populations. Eucalyptus species are well known for weak reproductive barriers and extensive hybridization within subgenera, but there is little knowledge of whether patterns of hybridization differ among subgenera. Here, we examine eucalypts of Western Australia’s Stirling Range to investigate how patterns of hybridization are associated with landscape and taxon age between the two largest Eucalyptus subgenera: Eucalyptus and Symphyomyrtus. In doing so, we tested a hypothesis of OCBIL (old, climatically buffered, infertile landscape) theory that predicts reduced hybridization on older landscapes.MethodsSingle nucleotide polymorphism markers were applied to confirm the hybrid status, parentage and genetic structure of five suspected hybrid combinations for subg. Eucalyptus and three combinations for subg. Symphyomyrtus.Key ResultsEvidence of hybridization was found in all combinations, and parental taxa were identified for most combinations. The older parental taxa assessed within subg. Eucalyptus, which are widespread on old landscapes, were identified as well-defined genetic entities and all hybrids were exclusively F1 hybrids. In addition, many combinations showed evidence of clonality, suggesting that the large number of hybrids recorded from some combinations is the result of long-term clonal spread following a few hybridization events rather than frequent hybridization. In contrast, the species in subg. Symphyomyrtus, which typically occur on younger landscapes and are more recently evolved, showed less distinction among parental taxa, and where hybridization was detected, there were high levels of introgression.ConclusionsReduced hybridization in subg. Eucalyptus relative to extensive hybridization in subg. Symphyomyrtus affirmed the hypothesis of reduced hybridization on OCBILs and demonstrate that clade divergence times, landscape age and clonality are important drivers of differing patterns of speciation and hybridization in Eucalyptus.

Ocbil theory was developed to better understand the origins, ecology and conservation of biodiversity and cultural diversity on the Earth's oldest, climatically buffered, most infertile landscapes (Ocbils), which are especially prominent in the Southwest Australian and Greater Cape Floristic Regions. Natural hybridization involves the mating of individuals from distinguishable populations, usually of distinct taxa, and often involves the production of later-generation derivatives from such matings. Drawing upon Edgar Anderson's Hybridized Habitat hypothesis and Arnold's modern development of Anderson's and Stebbins' ‘genetic exchange in fluctuating environments’ thesis, it is predicted that natural hybridization, introgression and hybrid speciation will be reduced in Ocbils and more common in Yodfels (young, often-disturbed, fertile landscapes) globally – the Reduced Hybridization Hypothesis for Ocbils. Evidence supporting this hypothesis is explored in herbarium and field data on hybridization rates and hybrid speciation in southwest Australia, contrasted with reviews of hybridization rates in other global regions. Further research is recommended and independent tests in South Africa and other countries with Ocbils would be instructive. The solitary Ocbil dwelling Eucalyptus × graniticola Hopper is described in supplementary material to exemplify the Reduced Hybridization Hypothesis.

Background Ocbil theory aims to develop hypotheses explaining the evolution and ecology of, and best conservation practices for, biota on very old, climatically buffered, infertile landscapes (Ocbils).

Plants pollinated by vertebrates are often visited by native and exotic insects foraging for pollen and nectar. We compared flower visitation rates, foraging behaviour, and the contribution to reproduction of nectar-feeding birds and the introduced honeybee Apis mellifera in four populations of the bird-pollinated Anigozanthos manglesii (Haemodoraceae). The behaviour of floral visitors was quantified with direct observations and motion-triggered and hand-held cameras. Pollinator access to flowers was manipulated by enclosure in netting to either exclude all visitors or to exclude vertebrate visitors only. Apis mellifera was the only insect observed visiting flowers, and the most frequent flower visitor, but primarily acted as a pollen thief. Although birds visited A. manglesii plants only once per week on average, they were 3.5 times more likely to contact the anther or stigma as foraging honeybees. Exclusion of birds resulted in 67% fewer fruits and 81% fewer seeds than flowers left open and unmanipulated. Unnetted flowers that were open to bird and insect pollinators showed pollen-limitation and a large variation in reproductive output within and between sites. Although honeybees have been shown to pollinate other Australian plants, compared to birds, they are highly inefficient pollinators of A. manglesii.

Pollinator behaviour has profound effects on plant mating. Pollinators are predicted to minimise energetic costs during foraging bouts by moving between nearby flowers. However, a review of plant mating system studies reveals a mismatch between behavioural predictions and pollen-mediated gene dispersal in bird-pollinated plants. Paternal diversity of these plants is twice that of plants pollinated solely by insects. Comparison with the behaviour of other pollinator groups suggests that birds promote pollen dispersal through a combination of high mobility, limited grooming, and intra- and interspecies aggression. Future opportunities to test these predictions include seed paternity assignment following pollinator exclusion experiments, single pollen grain genotyping, new tracking technologies for small pollinators, and motion-triggered cameras and ethological experimentation for quantifying pollinator behaviour.

To illustrate the morphology of sand-binding roots of Haemodoraceae, to conduct a comprehensive survey of the trait, spanning different climates across four continents, and to explore evolutionary hypotheses within a molecular phylogenetic framework. Sand-binding roots in Haemodoraceae were examined, measured and photographed in the field and on herbarium specimens. Photomicrographs were taken of southwest Australian species. The presence and absence of the sand-binding trait was mapped onto previously published phylogenies and an ancestral state reconstruction was performed. Sand grains were very tightly bound to the root surface by persistent root hairs in Haemodoraceae. The majority of genera and species were found to possess sand-binding roots and only 2 of the 14 genera, Conostylis and Tribonanthes, had sister taxa with and without the trait. The trait was recorded in tropical, sub-tropical and wet temperate species, but mainly in semi-arid species. Sand-binding roots were likely to have been present in the ancestor of the family and both sub-families. The presence of sand-binding roots is the probable ancestral condition for Haemodoraceae, associated with a high degree of phylogenetic conservatism and some secondary loss, notably in Conostylis. Experimental studies are needed to understand the ecological and evolutionary forces at work.

1. While rarely tested, the rarity of a species may be linked to the rarity of symbiotic partners. The requirement of many terrestrial plants to form a symbiosis with mycorrhizal fungi may limit the distribution and abundance of plant species. Here, in just the second test of the role of mycorrhiza in host species rarity, we investigate the influence of mycorrhizal specificity, distribution and ecological requirements in the genus Drakaea (Orchidaceae). 2. In situ seed baiting was used to resolve the distribution of mycorrhizal fungi for three common and two co-occurring rare species of Drakaea. Mycorrhizal fungi were isolated from wild adult orchids and protocorms and the ITS nrDNA regions sequenced. An in vitro study tested the range of Drakaea species of which each fungus can support germination. 3. All Drakaea species studied used a narrow monophyletic clade of Tulasnella endophyte for protocorm, seedling and adult plant stages. In situ seed baiting revealed that germination of Drakaea is largely restricted to the same microhabitat as that of the orchid. However, within this habitat Drakaea exhibit comparable germination to other Western Australian orchid genera. Rare and common Drakaea exhibited no difference in germination rates and both germinated in suitable habitat not currently occupied. 4. Synthesis. In contrast to the previous study of the role of mycorrhiza in plant rarity, there was no evidence that mycorrhizal specificity contributed to rarity in Drakaea. However, the formation of mycorrhiza being mostly restricted to a specific microhabitat may limit the abundance of Drakaea in some landscapes. In Drakaea, the highly specific pollination system of sexual deception may contribute to rarity. A trend towards high specificity in orchid mycorrhizal associations in southern Australia is hypothesized to result from the predominance of old landscapes affording the opportunity for specialization on a single or few mycorrhiza(s) best adapted to the landscape conditions.

As climate change increases vegetation combustibility, humans are impacted by wildfires through loss of lives and property, leading to an increased emphasis on prescribed burning practices to reduce hazards. A key and pervading concept accepted by most environmental managers is that combustible ecosystems have traditionally burnt because plants are fire adapted. In this opinion article, we explore the concept of plant traits adapted to fire in Mediterranean climates. In the light of major threats to biodiversity conservation, we recommend caution in deliberately increasing fire frequencies if ecosystem degradation and plant extinctions are to be averted as a result of the practice.

The papers in this issue of Kew Bulletin were delivered at a conference with the above title in the Jodrell Laboratory of the Royal Botanic Gardens, Kew on 12 – 16 October, 2009. Attracting 193 registrants from 34 countries, 50 speakers (including 10 keynote speakers) and 55 poster presenters, the conference proved most successful, as the papers herein highlight. Why was plant conservation chosen as the theme for such an important moment in the history of Kew? This certainly represents a significant shift in focus for the world’s largest botanical garden. A brief historical analysis may help place this shift in context. Although we have no first-hand history of Kew written for its 50th anniversary in 1809 or its centenary in 1859, the enterprise of empire was uppermost in the botanical science and economic botany of Kew during these eras under the respective leadership of Sir Joseph Banks and Sir William Hooker. By the sesquicentenary in 1909, staff had written a first history in which we were told (Bean & Thiselton-Dyer 1908): “Kew is the headquarters of botanical science in the British Empire — one might, without extravagance, say in the whole world. That is its highest purpose. What Greenwich is to astronomy, the National Gallery to painting, the British Museum to archaeology, such is Kew to botany.” The Director, Professor Sir William Thiselton-Dyer (1908) emphasised the important work of Kew on economic botany as well as taxonomy at the time: “Kew, in truth, has no politics or any aim but to accomplish useful work.” Fifty years later, in celebrating the bicentenary of Kew, the essential thrust of the organisation was identified both as a centre for botanical science and as a visitor attraction (Turrill 1959a): “The Royal Botanic Gardens, Kew, function essentially as a botanical not as a horticultural institution. Nevertheless, the Gardens proper as open to the general public are very beautiful and give recreation and pleasure to thousands of visitors who are not botanists.” This view of Kew as a centre of scientific excellence in botany was further reinforced by Vistas in Botany (Turrill 1959b), an edited volume of essays across the discipline written by global experts of the day. With considerable prescience, the then Director, Sir George Taylor wrote in Turrill (1959b): “The massive contributions to taxonomy [by Kew] have tended to overshadow the more limited output from the Jodrell Laboratory ... [for which] it is confidently expected that there will be early significant expansion in ... [its] activities]. ...Kew is proud of its long traditions of service to botanical science and horticulture and is confident in its power not only to maintain its high position but is poised to add further lustre to its reputation in the field of botanical research in its widest sense” (Taylor 1959). Over the subsequent 50 years, Kew’s Jodrell Laboratory has indeed risen to international eminence alongside the Herbarium, Library, Art and Archives, and RBG, Kew was inscribed on the World Heritage List in 2003, according contemporary global recognition of its collections, gardens and scientific programmes — see the recent histories of Kew by Desmond (2006) and Paterson (2008). While the focus on the science of plant and fungal diversity and the sustainable use of plants continue to underpin the work of Kew, dramatic changes in the global environment precipitated a new focus on conservation over the past four decades. Professor Sir Ghillean Prance, Director of Kew from 1988 to 1999, provides in this issue an authoritative review of how this happened. The change of focus towards plant conservation was initiated under the visionary directorship of Professor Jack Heslop-Harrison (McDowell 1996; Desmond 2006; Gunning & Heslop-Harrison 2005), and carried through by his successors and their staff and global partners to today’s cutting edge projects, including the Millennium Seed Bank Partnership. In recent years, Kew has formulated a new set of corporate strategies placed under the umbrella of the Breathing Planet Programme. This is a global partnership programme of existing activities which will be scaled up, resources willing, over the next decade with the aim of inspiring and delivering science-based plant and fungal conservation worldwide, enhancing the quality of life (Fig. 1).

Ancient landscapes, which have not been glaciated in recent times or disturbed by other major catastrophic events such as volcanic eruptions, are dominated by nutrient-impoverished soils. If these parts of the world have had a relatively stable climate, due to buffering by oceans, their floras tend to be very biodiverse. This review compares the functional ecophysiological plant traits that dominate in old, climatically buffered, infertile landscapes (OCBILS) with those commonly found in young, frequently disturbed, fertile landscapes (YODFELs). We show that, within the OCBILs of Western Australia, non-mycorrhizal species with specialised root clusters predominantly occur on the most phosphate-impoverished soils, where they co-occur with mycorrhizal species without such specialised root clusters. In global comparisons, we show that plants in OCBILs, especially in Western Australia, are characterised by very low leaf phosphorus (P) concentrations, very high N:P ratios, and very high LMA values (LMA = leaf mass per unit leaf area). In addition, we show that species in OCBILs are far more likely to show P-toxicity symptoms when exposed to slightly elevated soil P levels when compared with plants in YODFELs. In addition, some species in OCBILs exhibit a remarkable P-resorption proficiency, with some plants in Western Australia achieving leaf P concentrations in recently shed leaves that are lower than ever reported before. We discuss how this knowledge on functional traits can guide us towards sustainable management of ancient landscapes.

Analysis of cpDNA matK sequences for a total of 43 members of the succulent plant family Crassulaceae, including 24 taxa of Crassula, recovered a well-supported clade comprising Crassula species that is sister to the remainder of the family. The resulting topologies do not support the monophyly of the currently recognized subgenera of Crassula, as one member of subgenus Disporocarpa (C. crenulata) is placed as sister to an otherwise monophyletic subgenus Crassula. The major synapomorphy that has been used to recognize the latter subgenus is a base chromosome number of x = 7 versus a base of x = 8 in the other subgenus. We cannot assess the utility of this feature for defining subgenus Crassula because a chromosome count of C. crenulata has yet to be published. The five accessions of the recently resurrected segregate genus Tillaea (of 24 total Crassula species) included here were placed in four separate, well-supported lineages, one of which is greatly removed from the other four accessions. This suggests that this genus is not valid and should not be recognized. An initial examination of the evolution of habit indicates that a perennial habit is ancestral and that the annual habit is a feature that has been derived at least twice in the genus.

OCBIL theory aims to develop an integrated series of hypotheses explaining the evolution and ecology of, and best conservation practices for, biota on very old, climatically buffered, infertile landscapes (OCBILs). Conventional theory for ecology and evolutionary and conservation biology has developed primarily from data on species and communities from young, often disturbed, fertile landscapes (YODFELs), mainly in the Northern Hemisphere. OCBILs are rare, but are prominent in the Southwest Australian Floristic Region, South Africa’s Greater Cape, and Venezuela’s Pantepui Highlands. They may have been more common globally before Pleistocene glaciations. Based on the premise that natural selection has favoured limited dispersability of sedentary organisms, OCBILs should have elevated persistence of lineages (Gondwanan Heritage Hypothesis) and long-lived individuals (Ultimate Self Hypothesis), high numbers of localised rare endemics and strongly differentiated population systems. To counter such natural fragmentation and inbreeding due to small population size, ecological, cytogenetic and genetic mechanisms selecting for the retention of heterozygosity should feature (the James Effect). The climatic stability of OCBILs should be paralleled by persistence of adjacent semi-arid areas, conducive to speciation (Semiarid Cradle Hypothesis). Special nutritional and other biological traits associated with coping with infertile lands should be evident, accentuated in plants, for example, through water-foraging strategies, symbioses, carnivory, pollination and parasitism. The uniquely flat landscapes of southwestern Australia have had prolonged presence of saline lakes along palaeoriver systems favouring evolution of accentuated tolerance to salinity. Lastly, unusual resiliences and vulnerabilities might be evident among OCBIL organisms, such as enhanced abilities to persist in small fragmented populations but great susceptibility to major soil disturbances. In those places where it is most pertinent, OCBIL theory hopefully lays a foundation for future research and for better informed conservation management.

†Background The issue of determining the most appropriate rank for each accepted taxon fuels ongoing controversy throughout systematics. The particularly marked escalation of such issues in modern Australian orchid systematics merits examination, not only because of wider implications in taxonomy but also because of direct effects on studies of comparative biology and conservation management. †Scope This paper briefly reviews the causes of recent taxonomic turmoil for Australian orchids and outlines new research opportunities and conservation implications arising from an improved understanding of their molecular phylogenetics. †Conclusions DNA sequencing and intensified field work have contributed towards a much improved understanding of Australian orchid systematics. Great progress has been made in discerning monophyletic groups or clades. Fresh interpretations of morphological evolution have been made possible by comparisons with the results of DNA analyses. Significant conceptual shifts from polymorphic species concepts to biological and phylogenetic concepts have also elevated the discovery and description of new species. Consequently, over the past decade, the number of Australian orchid species recognized by taxonomists has risen from approx. 900 to 1200. Similarly, the number of genera recognized by some taxonomists has increased from 110 to 192, resulting in 45% of Australian species/subspecies being assigned a new generic epithet since 2000. At higher taxonomic levels, much of the recent controversy in Australian orchid systematics reflects a divergence in views about where to split and assign formal names within unequivocally monophyletic groups. Differences regarding typification in the case of Caladenia have added additional confusion and complexity. However, new insights into and research opportunities concerning speciation processes in orchids have arisen from the wealth of new data and discrimination of species. Robustly supported molecular analyses of most clades enable comparative biological studies of Australian orchids to be conducted as never before. Outstanding subjects exist for exploring pollination by sexual deception and understanding the intricacies of mycorrhizal relationships and orchid conservation biology.

Isoetes eludens, a new, highly localised, endemic species from the Kamiesberg, Northern Cape is described. The aquatic species grows in a shallow temporary gnamma or !gau (rock pool) in Kamiesberg gneiss at an altitude of 1,284 m. It is characterised by a short, strongly 3-lobed stem, relatively short, and broad estomate sporophylls, a complete velum, the presence of an outer sporangium sack (a feature not previously reported for the genus), graphite-black, laevigate megaspores with a narrow, but tall laesura, microspores with near smooth proximal surfaces but with a papillate distal surface, the absence of a ligule and labium, and simple roots with few root-hairs. The systematic relationship of the species is difficult to determine as a result of convergent evolution in the genus. The sporangium sack does not support an affinity with any of the known species. Further surveys are needed to establish the geographical extent and conservation status of this remarkable local endemic.

Understanding the drivers of orchid diversification and rarity may prove crucial to their conservation. The Orchidaceae is characterised by the presence of mycorrhizal endophytes and a diversity of pollination syndromes (Rasmussen 1995, Jersakova et al. 2006). The prevalence of pollination by deceit and the spe- cialised mycorrhizal relationships in some taxa have been implicated in the diversification of the family (Cozzolino & Widmer 2005, Otero & Flanagan 2006). Furthermore, interactions with habitat speciali- sation may act in concert with these attributes to play a critical role in orchid diversification (Gravendeel et al. 2004). The influence of these factors in determin- ing intrinsic rarity in orchids remains poorly known. Understanding the drivers of orchid diversification and rarity may prove crucial to their conservation. The Orchidaceae is characterised by the presence of mycorrhizal endophytes and a diversity of pollination syndromes (Rasmussen 1995, Jersakova et al. 2006). The prevalence of pollination by deceit and the spe- cialised mycorrhizal relationships in some taxa have been implicated in the diversification of the family (Cozzolino & Widmer 2005, Otero & Flanagan 2006). Furthermore, interactions with habitat speciali- sation may act in concert with these attributes to play a critical role in orchid diversification (Gravendeel et al. 2004). The influence of these factors in determin- ing intrinsic rarity in orchids remains poorly known.

Effective plant conservation involves careful con- sideration and difficult choices when investing limit- ed resources to conservation programs and policies. The conservation practice must integrate the under- standing of existing and future environmental threats, taxonomic distinctiveness, numbers of individuals in populations, reproductive biology, ex situ propagation and the maintenance of evolutionary processes influ- encing population distribution patterns. Effective plant conservation involves careful con- sideration and difficult choices when investing limit- ed resources to conservation programs and policies. The conservation practice must integrate the under- standing of existing and future environmental threats, taxonomic distinctiveness, numbers of individuals in populations, reproductive biology, ex situ propagation and the maintenance of evolutionary processes influ- encing population distribution patterns.

DNA sequence data from plastid matK and trnL-F regions were used in phylogenetic analyses of Diurideae, which indicate that Diurideae are not monophyletic as currently delimited. However, if Chloraeinae and Pterostylidinae are excluded from Diurideae, the remaining subtribes form a well-supported, monophyletic group that is sister to a "spiranthid" clade. Chloraea, Gavilea, and Megastylis pro parte (Chloraeinae) are all placed among the spiranthid orchids and form a grade with Pterostylis leading to a monophyletic Cranichideae. Codonorchis, previously included among Chloraeinae, is sister to Orchideae. Within the more narrowly delimited Diurideae two major lineages are apparent. One includes Diuridinae, Cryptostylidinae, Thelymitrinae, and an expanded Drakaeinae; the other includes Caladeniinae s.s., Prasophyllinae, and Acianthinae. The achlorophyllous subtribe Rhizanthellinae is a member of Diurideae, but its placement is otherwise uncertain. The sequence-based trees indicate that some morphological characters used in previous classifications, such as subterranean storage organs, anther position, growth habit, fungal symbionts, and pollination syndromes have more complex evolutionary histories than previously hypothesized. Treatments based upon these characters have produced conflicting classifications, and molecular data offer a tool for reevaluating these phylogenetic hypotheses.

A phylogenetic analysis of plastid DNA sequences from the trn L-F region corroborates the hypothesis that Haemodoraceae, a small monocotyledonous family centred in southwestern Australia, are monophyletic with relationships to Philydraceae, Pontederiaceae and Commelinaceae. It also supports the long-standing recognition of two subfamilies. In Conostylidoideae Tribonanthes falls in an isolated position, thus supporting its segregation as a recently recognized monogeneric tribe. Tribal status for Phlebocarya is not supported as this taxon is unexpectedly placed in Conostylideae as sister to Conostylis–Blancoa. Macropidia falls as sister to Anigozanthos . The DNA tree permits continued recognition of Macropidia and Blancoa as distinct genera, contrary to a recent morphological cladistic analysis. Haemodoroideae fall into two clades: ( Dilatris(Lachnanthes+Haemodorum )) and ( Xiphidium(Schiekia+Wachendorfia )). It is unlikely that Haemodoraceae are of Gondwanan origin, and the phylogenetic pattern indicates a largely relictual distribution with a recent radiation in Western Australia.

To examine claims that the role of botanical art in systematic botany is diminishing because of advances in photography, this review considers relevant literature and includes a quantitative analysis of trends in modern journals, monographs and floras. Our focus is on southern hemisphere systematic botany because, relative to the northern hemisphere, this is poorly represented in modern reviews of botanical art and photography. An analysis of all digitally available papers in Nuytsia, the Journal of the Adelaide Botanic Garden, Muelleria, Telopea, Austrobaileya and Systematic Botany established that, although photographic illustrations have increased since 2000, botanical illustrations have not always diminished. The cause of these trends is unknown, but it is likely to be due to several factors, including sourcing funding for production of botanical illustration, editorial preference for the use of illustrations or photographs, author preference for either illustrations or photographs, and moving to online publication, with no charges for colour reproduction. Moreover, the inclusion of botanical artists as co-authors in some scientific publications signals an ongoing and important role. Botanical illustration brings sharp focus and meticulous attention to detail regarding form and structure of plants. Photography is useful at the macro-scale for habitat and whole-plant traits, as well as at the micro-scale for anatomical textures and ultrastructure. These complementary approaches can be important components of taxonomic discovery, with the potential for a new role in modern trait analysis in molecular phylogenies.

BACKGROUND AND AIMS Worldwide, many plant species are confined to open, shallow-soil, rocky habitats. Although several hypotheses have been proposed to explain this habitat specificity, none has been convincing. We suggest that the high level of endemism on shallow soils is related to the edaphic specialization needed to survive in these often extremely drought-prone habitats. Previous research has shown that species endemic to ironstone communities in SW Australia have a specialized root morphology that enhances their chance to access fissures in the underlying rock. Here we test the generality of these findings for species that are confined to a shallow-soil habitat that is of much greater global significance: granite outcrops. METHODS We compared temporal and spatial root growth and allocation of three endemic woody perennials of SW Australian granite outcrop communities with those of congeners occurring on nearby deeper soils. Seedlings of all species were grown in 1·2 m long custom-made containers with a transparent bottom that allowed monitoring of root growth over time. KEY RESULTS The granite outcrop endemics mostly differed in a predictable way from their congeners from deeper soils. They generally invested a larger portion of their biomass in roots, distributed their roots faster and more evenly over the container and had a lower specific root length. In different species pairs the outcrop endemics achieved their apparent advantage by a different combination of the aforementioned traits. CONCLUSIONS Our results are consistent with earlier work, indicating that species restricted to different types of drought-prone shallow-soil communities have undergone similar selection pressures. Although adaptive in their own habitat in terms of obtaining access to fissures in the underlying rock, these root system traits are likely to be maladaptive in deeper soil habitats. Therefore, our results may provide an explanation for the narrow endemism of many shallow-soil endemics.

Keeley et al. [1] have responded to our recent article [2] inwhich we suggest that many of the traits that are com-monly assumed to be fire adaptations in Mediterraneanecosystem plants evolved with selective factors other thanfire.Theyagreewithusthat‘Distinguishingbetweentraitsthat are adaptations originating in response to fire orexaptations originating in response to other factors maynot always be possible’, but nevertheless conclude that‘Traits such as resprouting, serotiny and germination byheat and smoke are adaptive in fire-prone environments.’We agree that these traits enhance fitness in fire-proneenvironments, but this does not mean that they are ‘fireadaptations’. As the late George C. Williams so eloquentlyput it when emphasising the importance of design consid-erations in evolutionary theory [3]: ‘evolutionary adapta-tion is a special and onerous concept that should not beused unnecessarily, and an effect (a fitness-increasing useto which a trait is put) should not be called a function (adesigned fitness-increasing use) unless it is clearly pro-duced by design and not by chance’. Keeley et al. [1],intheir loose use of the evolutionary concept of ‘adaptation’,precisely exemplify our point. They admit that we ‘...raisesome legitimate questions about traits interpreted to beadaptiveinfire-prone environments’butarguethatwefailtodemonstratethatthetraitsinquestionaroseinresponseto other environmental factors. We agree, but believe theburden of proof lies with those who identify these as fireadaptations and the matter can only be resolved by appro-priate phylogenetic analyses.The assertion that ‘one of the unfortunate sides’ of ourpaper ‘is that it uses ‘evolutionary arguments to drawconclusions about appropriate fire management decisions’suggests that Keeley et al. [1] have not grasped our mainpoint.Ourconcernisthatpoorlyunsubstantiatedclaimsofadaptation to fire made by many fire managers (and someecologists) without adequate evidence are used to justifyburning across a range of regimes with impunity. Appro-priate management strategies must take into account theresilience of the vegetation that is being burned and theconcept that ‘plants need fire’ needs scientific backing [4].The distinction between ‘adaptation’ and ‘exaptation’ is afine one, but it might invoke quite different responses infire management practice. A belief in ‘adaptation to fire’implies that fire will not cause long-lasting harm to plantsand legitimises the burning regime, whereas ‘tolerance tofire’ implies that there might be limits.Keeley et al. [1] suggest that exaptations function aswell as adaptations in enhancing fitness in a given envi-ronment, and this might well be true, but there is noevidence of this and the application of the ‘cautionaryprinciple’ remains appropriate when dealing with a com-plex factor such as fire. They maintain that ‘...plants arenot adapted to fire per se but to fire regimes’. It is obvious,however, that current human-induced fire regimes arevery different from those of the geological past, whichhadfireintervalsof30–100years,forexample,inthesouthof Western Australia [5].WeareheartenedbyKeeleyetal.[1]who‘...sharethoseconcerns that too frequent prescription burning can nega-tively affect biodiversity and ecosystem processes’ and wehopethatour paper[2]willstimulate much-needed debateand future research on the impact of frequent fire in someof the most important biodiversity hotspots around theworld [6].

Ancient landscapes, which have not been glaciated in recent times or disturbed by other major catastrophic events such as volcanic eruptions, are dominated by nutrient-impoverished soils. If these parts of the world have had a relatively stable climate, due to buffering by oceans, their floras tend to be very biodiverse. This review compares the functional ecophysiological plant traits that dominate in old, climatically buffered, infertile landscapes (OCBILS) with those commonly found in young, frequently disturbed, fertile landscapes (YODFELs). We show that, within the OCBILs of Western Australia, non-mycorrhizal species with specialised root clusters predominantly occur on the most phosphate-impoverished soils, where they co-occur with mycorrhizal species without such specialised root clusters. In global comparisons, we show that plants in OCBILs, especially in Western Australia, are characterised by very low leaf phosphorus (P) concentrations, very high N:P ratios, and very high LMA values (LMA = leaf mass per unit leaf area). In addition, we show that species in OCBILs are far more likely to show P-toxicity symptoms when exposed to slightly elevated soil P levels when compared with plants in YODFELs. In addition, some species in OCBILs exhibit a remarkable P-resorption proficiency, with some plants in Western Australia achieving leaf P concentrations in recently shed leaves that are lower than ever reported before. We discuss how this knowledge on functional traits can guide us towards sustainable management of ancient landscapes. © 2010 Springer Science+Business Media B.V.

Recent phylogenetic analysis has placed the aquatic family Hydatellaceae as an early-divergent angiosperm. Understanding seed dormancy, germination and desiccation tolerance of Hydatellaceae will facilitate ex situ conservation and advance hypotheses regarding angiosperm evolution.Seed germination experiments were completed on three species of south-west Australian Hydatellaceae, Trithuria austinensis, T. bibracteata and T. submersa, to test the effects of temperature, light, germination stimulant and storage. Seeds were sectioned to examine embryo growth during germination in T. austinensis and T. submersa.Some embryo growth and cell division in T. austinensis and T. submersa occurred prior to the emergence of an undifferentiated embryo from the seed coat ('germination'). Embryo differentiation occurred later, following further growth and a 3- to 4-fold increase in the number of cells. The time taken to achieve 50 % of maximum germination for seeds on water agar was 50, 35 and 37 d for T. austinensis, T bibracteata and T. submersa, respectively.Seeds of Hydatellaceae have a new kind of specialized morphophysiological dormancy in which neither root nor shoot differentiates until after the embryo emerges from the seed coat. Seed biology is discussed in relation to early angiosperm evolution, together with ex situ conservation of this phylogenetically significant group.

Botanic gardens have great and longstanding strengths in the exploration and documentation of plant diversity – including systematics, horticultural science, and most recently molecular phylogenetics. However, in terms of mainstream plant science today, with its dominantly reductionist focus, research in botanic gardens is often neglected. Using the conventional criteria few botanic garden plant scientists rank as leaders in the plant science community and the work undertaken in botanical gardens is often viewed as peripheral to current societal problems and “cutting-edge” research.

Events around the world this year celebrate the bicentenary of the birth of Charles Darwin (1809-1882) and the sesquicentenary of publication of his most important work, The Origin of Species (Darwin 1859). The associated plethora of books and papers now appearing to commemorate Darwin's work continue the traditional emphasis on his zoological and geological contributions. There has been some recent attention directed towards Darwin's relatively unsung but significant accomplishments as a botanist. Here, we bring together a review of Darwin's botanical discoveries and experiments and relevant aspects of his geological investigations, with a focus on the Southern Hemisphere. This is a relatively unexplored aspect of Darwin's contributions that yields some new insights meriting future research.

The comparative longevity of seeds of species from the early-angiosperm group, Hydatellaceae, along with other temporary wetland aquatics from the South-west Australian Floristic Region were tested under standard experimental storage conditions. In contrast to recent hypotheses proposing that seeds from basal angiosperm species may be short-lived in storage, seeds of the Hydatellaceae species (Trithuria submersa Hook.f. and T. austinensis D.D.Sokoloff, Remizowa, T.Macfarlane and Rudall) were longer-lived than the other temporary wetland aquatic species tested. Seeds of Glossostigma drummondii Benth. (Scrophulariaceae), Myriophyllum petreaum Orchard and M. balladoniense Orchard (Haloragaceae), lost viability quickly and are thus predicted to be short-lived in seed bank storage. To assist seed bank conservation programs, the effect of seed moisture content on the viability of seeds stored for 1, 6 and 12 months at −18°C or in vapour phase cryopreservation (−150°C) was determined. Seeds of all species survived storage at both temperatures for up to 12 months, provided seed equilibrium relative humidity was below ~50%. Given the high conservation value of Hydatellaceae species and the potential short-lived nature of seeds of some of the species, we recommend that ex situ conservation programs for these aquatic species should consider cryopreservation as a means to maximise the longevity of their seeds.

Caladenia contains 376 species and subspecies, of which almost all are endemic to temperate and southern semiarid Australia. Eleven species occur in New Zealand, 10 of which are endemic, and one species is widely distributed in eastern Australia and the western Pacific. Only three species occur in both south-western and south-eastern Australia. At subgeneric level, Drakonorchis is endemic to the South-west Australian Floristic Region (SWAFR), Stegostyla to eastern Australia and New Zealand, whereas three subgenera, Calonema, Phlebochilus and Elevatae occur on both sides of the Nullarbor Plain. Subgenus Caladenia is primarily eastern Australian but also extends to the western Pacific. The largest subgenera (Calonema and Phlebochilus) have radiated extensively, with Calonema exhibiting a greater concentration of species in more mesic parts of the SWAFR than Phlebochilus. Within the SWAFR, the major biogeographic division within Caladenia follows the 600-mm isohyet. Within rainfall zones, biogeographic districts for Caladenia correlate with a combination of underlying geology and surface soils. Areas of high endemism contain diverse edaphic environments. Climatic and edaphic requirements are likely to be key drivers of rarity in Caladenia, although these parameters may be acting in concert with mycorrhizal and pollinator specificity.

Three new rare taxa allied to the conspicuous, common four-winged mallee (Eucalyptus tetraptera Turcz.) are described. E. sweedmaniana is a large-leaved and prostrate coastal mallee known only from Mount Arid, Western Australia. E. brandiana, a non-lignotuberous mallet, occupies spongolite hilltops and escarpments near the Fitzgerald River Inlet in Fitzgerald River National Park, Western Australia. A single hybrid mallet, E. arborella × brandiana, is described from the type locality of E. brandiana. Both new species and the new hybrid show potential for horticultural use, given their compact habit, large leaves and conspicuous red floral hypanthia and fruits. E. arborella × brandiana and E. brandiana are particularly at risk, being highly localised endemics that are killed by fire.

Caladenia is a genus of more than 250 species of geophytic orchids in the Tribe Diurideae endemic to the Australasian Region. The genus in this broad sense has an exceptional diversity of insect pollination adaptations among its colourfully adorned species, from food-rewarding generalists to specialists achieving pollination by sexual deception of male thynnid wasps. The exploration of diversity in Caladenia involves many of the great names in the foundation of Australasian plant systematics, as well as reflecting a remarkable second phase of discovery and description over the past three decades. Molecular phylogenetics has greatly clarified relationships of Caladenia and established six major clades within the genus. Some researchers regard these clades as genera themselves, whereas they are treated as subgenera herein to maximise nomenclatural stability and information retrieval. More work is needed to adequately document relationships within each of these clades, and disputed matters of typification greatly influence nomenclature applied to many species if the six clades are recognised as genera. Given the relatively recent and ongoing discovery of so many new species in Caladenia, the biology of these orchids is only now being documented comprehensively. Significant advances in pollination ecology, mycorrhizal studies, horticulture and conservation biology are emerging that highlight the extraordinary ecological sensitivity and conservation vulnerability of the genus. Indeed, the high species number and complex biotic connections have resulted in no other genus of terrestrial orchids possessing such a large number of rare and threatened taxa. Some of this rich body of new data is presented by a diverse range of laboratories and researchers in this special issue.

The morphology and development of flowers and pseudanthia of Calycopeplus paucifolius are described in detail in the context of recent molecular phylogenies of the tribe Euphorbieae and a recent comparative developmental analysis of other taxa within this tribe. Calycopeplus resembles subtribes Neoguillauminiinae and Anthosteminae in some respects (dichasial formation of male flowers within male partial inflorescences, late formation of a constriction in male and female flowers and early formation of a female perianth), but resembles Dichostemma (subtribe Anthosteminae) in possessing only four male partial inflorescences. Calycopeplus and all other Euphorbieae possess only three carpels, except Dichostemma, which has four carpels per female flower. The studied species differs from the closely related Neoguillauminia cleopatra (subtribe Neoguillauminiinae) in that only four nectaries are formed, situated on the rim of the cuplike involucre (in Neoguillauminia 8–10 nectaries arise directly from the base of the pseudanthium). In contrast to all other studied Euphorbieae with trimerous gynoecia, the unpaired carpel of C. paucifolius is oriented in an upper/adaxial position (it lies in the lower/abaxial position in all other studied taxa). On the basis of these results we discuss possible pathways of cyathium evolution and the role of the cyathium as a possible key innovation within Euphorbieae. ‘Calycopeplus is as perfect an example of a connecting link as a morphologist may wish for.’ (Croizat 1937, p. 404)

Ecological restoration of degraded habitats is a major conservation activity requiring the collection of large amounts of native seed. Seed production and the genetic quality of seed may be influenced by properties of the source population, such as population size and fragmentation, potentially having an impact on restoration goals. We assessed the population-size effects on seed production and seedling performance in two Western Australian wheatbelt eucalypts, Eucalyptus salmonophloia F.Muell. and E. salubris F.Muell. Both species were historically widespread and dominant, but, as a consequence of land-clearing for agriculture, now exist as small, highly fragmented populations throughout the western half of their range. Given their former importance in the landscape, these species will be critical in ecological restoration of the region. We assessed small (n = 6–12) and large (n > 200) remnant populations in a highly fragmented landscape and compared these to large unfragmented populations. Seed number per capsule was dependent on population size and fragmentation for E. salubris, but not for E. salmonophloia. Large, unfragmented populations of E. salubris produced more than twice the number of seeds per capsule (mean = 2.95) than small and/or fragmented populations. However, seed germination, seed weight, seedling survival and seedling vigour to 1 year were independent of population size or fragmentation in both species. Our results suggest that reduced population size and increased fragmentation can negatively affect pollen quantity and/or quality, thereby limiting seed production, although no fitness effects were observed post-seed maturation. We suggest that the relative absence of post-seed maturation fitness effects in these small fragmented populations are a consequence of (1) wide outcrossing resulting from long-distance dispersal of pollen by highly mobile birds among fragmented populations and/or (2) efficient pre- or post-zygotic selection against more homozygous zygotes within fruits so that only relatively outbred seeds mature. The consequences on seed collection for ecological restoration of reduced population size and increased fragmentation for these eucalypts may be fewer seeds for the same collecting effort, but no apparent fitness effects of mature seeds. However, caution should be exercised when harvesting seed from these smaller populations, as over-harvesting may have an impact on recruitment and hence long-term persistence.

Drakaea Lindley, 1840 is a genus of 10 species of geophytic orchids endemic to the South-west Australian Floristic Region. The genus is renowned for its morphological and chemical adaptations, achieving pollination by sexual deception of male thynnid wasps. The history of taxa in Drakaea has been one of dispute and confusion right to the present day. Here we provide a revision of the genus, the first made by using modern collections and field data, formalising names for undescribed taxa featured by Hoffman and Brown (1992, 1998), several of which are threatened with extinction. We describe six new species: D. andrewsiae, D. concolor, D. confluens, D. gracilis, D. isolata and D. micrantha. Experimental baiting of male wasps has helped show the specific status of some of these new taxa. Molecular phylogenetic research is needed to clarify relationships and patterns of speciation in the genus. Five of the 10 Drakaea species are legally protected under the Western Australian Wildlife Conservation Act and the Commonwealth Environment Protection and Biodiversity Conservation Act, signalling the ongoing need for research and management to ensure the conservation of this unique part of Australia’s orchid heritage. D. andrewsiae has been recorded only three times from the Gnowangerup–Tunney district. Urgent surveys are needed to establish its conservation status.

We uphold the generic rank of Paracaleana on the basis of its divergent pollination syndrome (sexual deception of male thynnid wasps compared with pollination of Caleana by male sawflies), recent DNA sequence data demonstrating monophyly, and nomenclatural stability. Ten of the 13 species recognised herein are new, all endemic to the South-west Australian Floristic Region: Paracaleana alcockii, P. brockmanii, P. dixonii, P. gracilicordata, P. granitica, P. hortiorum, P. lyonsii, P. parvula, P. terminalis and P. triens. Although some of these taxa have subtle morphological differences, primarily of labellum morphology, evidence from other Australian orchid genera whose flowers sexually deceive wasp pollinators indicates that reproductive isolation is probable among close sister taxa in Paracaleana. Moreover, phenological, ecological and geographical differences help separate morphologically close sister taxa. P. disjuncta D.L. Jones is considered to extend from Victoria and South Australia west into the South-west Australian Floristic Region, where James Drummond first collected the species, probably in 1838. Additional research is needed on pollinators, molecular phylogeny, possibly undescribed taxa within P. nigrita and on the few putative hybrids identified in the genus.

Nomenclatural confusion has been generated regarding the large Australasian terrestrial orchid genus Caladenia following publication from 2001 onwards of three major treatments of Caladeniinae. Here, we review concepts for Caladenia and allied genera in the subtribe, we revise three sister genera of Caladenia (Cyanicula, Ericksonella and Pheladenia), and we present an annotated nomenclatural checklist with many new synonymies and some new combinations. A revised circumscription of ten genera in the Caladeniinae is presented, including both Adenochilus and Eriochilus, which have recently been segregated as monogeneric subtribes by others. We argue for retaining Caladenia in the broad sense, largely reflecting Robert Brown's original concept, differing only in the recognition as genera of Cyanicula, Pheladenia, and Leptoceras, as well as two monotypic genera not known to Brown but later described as species of Caladenia (Praecoxanthus and Ericksonella). Thus Caladenia remains a large Australasian genus of terrestrial orchids with 243 species and six subgenera. This approach maximises nomenclatural stability while ensuring that hypothesised monophyly is upheld in the light of molecular phylogenetics analyses. The valid type for Caladenia is C. carnea, while that for Caladenia sect. Calonema is C. longicauda. The genus Jonesiopsis and generic combination Phlebochilus (Benth.) Szlach. were validly published. These conclusions call into question many recently erected taxa and combinations of other authors. Synonyms of Caladenia include Arachnorchis, Calonemorchis, Drakonorchis, Jonesiopsis, Petalochilus, Phlebochilus and Stegostyla. Pentisia is a synonym of Cyanicula. Calonema (Lindl.) Szlach. and Calonema (Lindl.) D.L. Jones and M.A. Clem. are invalid generic combinations as the name Calonema had already been used for a fungal genus. New taxa described herein include Ericksonella, Cyanicula subgenus Trilobatae, C. aperta, C. ixioides subsp. candida, × Cyanthera and × C. glossodioides. New combinations include Caladenia subgenus Stegostyla (D.L. Jones and M.A. Clem.) Hopper and A.P. Br., C. graniticola (Hopper and A.P. Br.) Hopper and A.P. Br., C. saccata (R.S. Rogers) Hopper & A.P. Br., C. orientalis (G.W. Carr) Hopper & A.P. Br., and C. villosissima (G.W. Carr) Hopper & A.P. Br., and Ericksonella saccharata (Reichb.f.) Hopper and A.P.Br.

The tetraploid Conostylis stylidioides (n= 16) has been proposed to be a stabilised hybrid between the diploid (n = 8) species C. prolifera and C. candicans because of morphological and geographical intermediacy, as well as a polyploid chromosome number. To test this hybrid-origin hypothesis, we used the DNA-fingerprinting technique amplified fragment length polymorphism (AFLP) and measured genetic variation within these taxa, as well as the putative outgroups C. robusta and C. aculeata. One AFLP primer pair generated 192 dominant markers for 36 samples from these species, of which 189 were polymorphic. Polymorphism within populations was uniformly high for all species, with 66–86% of all fragments polymorphic and estimates of heterozygosity ranging from 0.36 to 0.41. Ordination, UPGMA and maximum parsimony analyses of these genetic data consistently clustered species, supporting the current species’ level taxonomy. The intermediate placement of C. stylidioides between C. proliferaand C. candicans on the maximum parsimony tree supports the hybrid-origin hypothesis, although other interpretations are possible. The phenetic results for AFLP data, in which C. stylidioides is not strictly intermediate between C. prolifera and C. candicans, are either concordant with recent research suggesting that rapid intra- and inter-genomic rearrangements occur with the origin of polyploid taxa, or indicate an ancient hybridisation event. While our results do not reject the hybrid origin hypothesis, the extremely high levels of genetic variation detected with AFLP within these populations, in combination with extensive genomic reorganisation with the origin of C. stylidioides and the possibility of independent origins for different populations, make it difficult to confidently exclude other scenarios.

Sobre la base de los datos de la secuencia de ADN, se confirma que las afinidades del genero Granitites (Rhamnaceae) recientemente descrito del sudoeste de Australia estan con Alphitonia, como sugirio Rye (1996), en lugar de miembros de Pomaderreae, como pensaron autores anteriores. . Los hallazgos de este estudio proporcionan una confirmacion molecular de que algunos componentes de la flora del suroeste de Australia pueden ser reliquias de antiguos linajes de la selva tropical

Conservation of Australian plants depends on a spectrum of activities from descriptive and experimental biological studies to active management and restoration of wild ecosystems by local communities who value their native biota. On the basis of the premise that available resources for conservation will not allow for all threatened biodiversity to be saved, some systematists and conservation geneticists argue that phylogenetic relationships should be used to set conservation priorities. The principle advocated is that characters, not species number, should become the currency of conservation, that cladistic analysis of phylogenetic pattern provides a predictive means of modelling the underlying distribution of characters among taxa, and that priority should be given to that subset of taxa with the greatest number of character states. This approach has been applied for some time in the conservation of genetic resources within species (e.g. Eucalyptus caesia), and has been an extra impetus for action with taxonomically isolated endangered species such as the recently discovered araucarian Wollemi pine (Wollemia nobilis). However, most plant conservation activity in Australia has paid little heed to phylogenetic relationships. Degree of threat has been a driving motivation, with endangered species receiving legislative and management attention irrespective of their systematic relationships. Moreover, the current revolution in understanding plant phylogeny associated with DNA sequence studies highlights the need for caution in accepting results of morphologically based analyses. A series of studies on the kangaroo paw and bloodroot family Haemodoraceae highlights this cautionary tale. The derivation of phylogenetic principles relevant to ecosystem and landscape processes is a new field of some promise to conservation managers. An understanding of the Gondwanan origins and landscape evolution of the south-west Australian flora provides a useful case study. Scaling up phylogenetic knowledge of genetic resources within species, and of the evolutionary relationships of taxa to an integrated overview of best management practices for all taxa at the local landscape level, is perhaps the most effective contribution phylogeneticists might make to help conserve Australian plants.

Conservation of Australian plants depends on a spectrum of activities from descriptive and experimental biological studies to active management and restoration of wild ecosystems by local communities who value their native biota. On the basis of the premise that available resources for conservation will not allow for all threatened biodiversity to be saved, some systematists and conservation geneticists argue that phylogenetic relationships should be used to set conservation priorities. The principle advocated is that characters, not species number, should become the currency of conservation, that cladistic analysis of phylogenetic pattern provides a predictive means of modelling the underlying distribution of characters among taxa, and that priority should be given to that subset of taxa with the greatest number of character states. This approach has been applied for some time in the conservation of genetic resources within species (e.g. Eucalyptus caesia), and has been an extra impetus for action with taxonomically isolated endangered species such as the recently discovered araucarian Wollemi pine (Wollemia nobilis). However, most plant conservation activity in Australia has paid little heed to phylogenetic relationships. Degree of threat has been a driving motivation, with endangered species receiving legislative and management attention irrespective of their systematic relationships. Moreover, the current revolution in understanding plant phylogeny associated with DNA sequence studies highlights the need for caution in accepting results of morphologically based analyses. A series of studies on the kangaroo paw and bloodroot family Haemodoraceae highlights this cautionary tale. The derivation of phylogenetic principles relevant to ecosystem and landscape processes is a new field of some promise to conservation managers. An understanding of the Gondwanan origins and landscape evolution of the south-west Australian flora provides a useful case study. Scaling up phylogenetic knowledge of genetic resources within species, and of the evolutionary relationships of taxa to an integrated overview of best management practices for all taxa at the local landscape level, is perhaps the most effective contribution phylogeneticists might make to help conserve Australian plants.

Conservation of Australian plants depends on a spectrum of activities from descriptive and experimental biological studies to active management and restoration of wild ecosystems by local communities who value their native biota. On the basis of the premise that available resources for conservation will not allow for all threatened biodiversity to be saved, some systematists and conservation geneticists argue that phylogenetic relationships should be used to set conservation priorities. The principle advocated is that characters, not species number, should become the currency of conservation, that cladistic analysis of phylogenetic pattern provides a predictive means of modelling the underlying distribution of characters among taxa, and that priority should be given to that subset of taxa with the greatest number of character states. This approach has been applied for some time in the conservation of genetic resources within species (e.g. Eucalyptus caesia), and has been an extra impetus for action with taxonomically isolated endangered species such as the recently discovered araucarian Wollemi pine (Wollemia nobilis). However, most plant conservation activity in Australia has paid little heed to phylogenetic relationships. Degree of threat has been a driving motivation, with endangered species receiving legislative and management attention irrespective of their systematic relationships. Moreover, the current revolution in understanding plant phylogeny associated with DNA sequence studies highlights the need for caution in accepting results of morphologically based analyses. A series of studies on the kangaroo paw and bloodroot family Haemodoraceae highlights this cautionary tale. The derivation of phylogenetic principles relevant to ecosystem and landscape processes is a new field of some promise to conservation managers. An understanding of the Gondwanan origins and landscape evolution of the south-west Australian flora provides a useful case study. Scaling up phylogenetic knowledge of genetic resources within species, and of the evolutionary relationships of taxa to an integrated overview of best management practices for all taxa at the local landscape level, is perhaps the most effective contribution phylogeneticists might make to help conserve Australian plants.

Estimates of parameters of the mixed mating model were made for three populations of the bird-pollinated arid zone eucalypt, Eucalyptus rameliana F. Muell. Levels of outcrossing ((t) over cap) varied significantly between populations from mixed mating with substantial selfing ((t) over cap = 0.54) to almost completely outcrossed ((t) over cap = 0.95). Comparison of single-locus and multilocus estimates suggested that the drop in outcrossing was due to increased self-pollination. The lowest outcrossing rate was attributed to the reduced ability of a population with low numbers of buds to attract bird pollinators. Outcrossing rates in E. rameliana are proposed to be a more direct reflection of pollination than estimates made for mass flowering, i.e. small-fruited eucalypts. The distribution of allozyme diversity in E. rameliana also appeared to reflect the impact of bird pollinators in promoting gene flow as well as the species capacity for outcrossing and introgression. Levels of diversity were comparable with other eucalypts, but the proportion of diversity between populations (GST = 9.2%) was only about half the mean for other eucalypts. Genetic distances between populations were low, but there was same significant differentiation of populations which was attributed to non-random bird migrations. The importance of bird pollination in the mating system and the distribution of genetic diversity in E. rameliana emphasises that enough habitat to support nomadic birds should be preserved in order to conserve this eucalypt species.

Background Carboxylate-releasing cluster roots of Proteaceae play a key role in acquiring phosphorus (P) from ancient nutrient-impoverished soils in Australia. However, cluster roots are also found in Proteaceae on young, P-rich soils in Chile where they allow P acquisition from soils that strongly sorb P. Scope Unlike Proteaceae in Australia that tend to proficiently remobilize P from senescent leaves, Chilean Proteaceae produce leaf litter rich in P. Consequently, they may act as ecosystem engineers, providing P for plants without specialized roots to access sorbed P. We propose a similar ecosystem-engineering role for species that release large amounts of carboxylates in other relatively young, strongly P-sorbing substrates, e.g. young acidic volcanic deposits and calcareous dunes. Many of these species also fix atmospheric nitrogen and release nutrient-rich litter, but their role as ecosystem engineers is commonly ascribed only to their diazotrophic nature. Conclusions We propose that the P-mobilizing capacity of Proteaceae on young soils, which contain an abundance of P, but where P is poorly available, in combination with inefficient nutrient remobilization from senescing leaves allows these species to function as ecosystem engineers. We suggest that diazotrophic species that colonize young soils with strong P-sorption potential should be considered for their positive effect on P availability, as well as their widely accepted role in nitrogen fixation. Their P-mobilizing activity possibly also enhances their nitrogen-fixing capacity. These diazotrophic species may therefore facilitate the establishment and growth of species with less-efficient P-uptake strategies on more-developed soils with low P availability through similar mechanisms. We argue that the significance of cluster roots and high carboxylate exudation in the development of young ecosystems is probably far more important than has been envisaged thus far.