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Zieria buxijugum , Z. formosa , and Z. parrisiae are three closely related, Critically Endangered species of questionable taxonomic validity that occur within six kilometres of each other on the south coast of New South Wales, Australia. We investigated genetic relationships and diversity of these species, along with two related but taxonomically distinct congeners, Z. granulata and Z. tuberculata , and a possible undescribed taxon, Z. aff. tuberculata. Double-digest restriction-site associated sequencing (ddRADseq) was used to generate anonymous genomic loci that were used for phylogenetic, network, and genetic structure analyses, and for estimating genetic diversity of the threatened species. Our results support the current taxonomic status of Z. buxijugum , Z. formosa , and Z. parrisiae , and suggest that Z. aff. tuberculata warrants recognition as a distinct species. We detected no evidence of inbreeding in the three Critically Endangered species, and found their genetic diversity to be similar to that of the more widespread species Z. granulata and Z. tuberculata. Comparison of plant material held in ex situ collections at the Australian National Botanic Gardens with wild plants highlighted several genotypes of the Critically Endangered species that are not represented in the ex situ collection, and we provide suggestions for the future inclusion of those unrepresented genotypes. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Conservation seed banks maintain collections of many seed‐bearing plant species, providing germplasm and data to support management of wild populations. However, a proportion of plant species produce seeds that are difficult to collect, dry, store and utilise; these are known as 'exceptional' species. Here we tested a framework for identifying exceptional species, to document examples and provide case studies within the Australian flora. We present a workflow that may be used to identify additional exceptional species, and direct efforts to establish appropriate collection types (seeds and/or living collections, tissue culture or cryopreservation) for their ex situ conservation. Summary: Seed banking is well established to contribute to the conservation of many seed‐bearing plant species ex situ for future use in restoration, translocation, agriculture and horticulture. In Australia, over 67% of currently listed threatened plants are represented in conservation seed banks. However, there are challenges to conserving the full extent of plant diversity in seed banks, with growing recognition that we need to think beyond conventional seed banking methods to conserve 'exceptional' plant species that are difficult to collect, store and germinate. We examine how the framework for identification of such species can be applied to the Australian flora, using examples from the recently published guidelines for 'Plant Germplasm Conservation in Australia' and case studies and data arising from the Australian Academy of Science Fenner Conference on the Environment 'Exceptional Times, Exceptional Plants'. We present a workflow to assist conservation decision‐makers and practitioners in identifying exceptional species and overcoming barriers to storage of germplasm, enabling appropriate ex situ collection types to be established via seeds, living collections, tissue culture, cryopreservation or a combination of these. Australia's seed conservation sector continues to expand, with increasing expertise, facilities and networks established to conserve a diversity of plant species; however, resolving the challenges relating to each exceptionality factor requires significantly more time, labour and collaboration than current capacity allows. Understanding the barriers to conservation and production of healthy plants, via germination or other methods of propagation, is a critical component of conserving species long‐term and ultimately returning plants to the landscape. [ABSTRACT FROM AUTHOR]

Context. Australia's tropical montane cloud forests (TMCF) exhibit exceptional species richness and endemism. Determinants of regeneration via seed of these species are next to unknown, limiting our ability to quantify and project their vulnerability to climate change. The ratio of red to far-red light (R:FR) has been shown to influence seed germination of many tropical species. Aims. We investigated germination of six previously unstudied TMCF species in relation to the presence or absence of light (light/dark) and light quality (R:FR). We hypothesised that increased R:FR would lead to increased germination and that small-seeded species would be more likely to have a light requirement and be less sensitive to R:FR compared to larger-seeded species. Methods. Sunlight and polyester filters were used to create a gradient of R:FR ranging from0.1 to 1.14. Seeds were also sown in constant darkness. Key results. Across species we saw varying germination responses. Three of the four smallest-seeded species exhibited an absolute light requirement for germination and did not discriminate between different R:FR. Germination of the small-seeded TMCF endemic Dracophyllum increased exponentially with increasing R:FR. Germination of the largest-seeded species was inhibited by both low and high R:FR, and germination was higher in constant darkness than diurnal light/dark. All six species were able to germinate at remarkably low R:FR values. Conclusions. Light affects seed germination of Australia's TMCF plant species in a variety of ways. Implications. The findings of this study provide insights into plant recruitment in situ, and the acclimation potential of these species under reduced R:FR predicted for the future. [ABSTRACT FROM AUTHOR]

Summary: Critically endangered grasslands and grassy woodlands were once widespread across south‐eastern Australia. However, more than 200 years of European land use means less than 1% of their pre‐European extent remains today. Conservation and restoration of these ecosystems involves reintroducing fire to periodically reduce competition and allow smaller species to establish. Furthermore, seeds of native species are sown – but often fail to establish as many forbs and grasses are hard‐to‐germinate. Therefore, data on how these species respond to fire‐related germination cues, such as smoke and heat, can benefit our understanding of both how species respond to fire and identify treatments which can be used to increase germination. We conducted a germination trial to determine if smoke and heat cues increase percent germination and germination speed of 55 common grassy ecosystem species. Fire cues increased germination speed and/or percent germination of 44 of the 55 study species. These results have three implications for grassy ecosystem conservation and restoration: (i) fire may aid conservation by maximizing germination of native species; (ii) pre‐treating seed with smoke and/or heat prior to sowing may increase germination when restoring these ecosystems via direct seeding; and (iii) smoke and heat can be used to increase germination when growing seedlings for plantings. [ABSTRACT FROM AUTHOR]

Species' movements affect their response to environmental change but movement knowledge is often highly uncertain. We now have well‐established methods to integrate movement knowledge into conservation practice but still lack a framework to deal with uncertainty in movement knowledge for environmental decisions. We provide a framework that distinguishes two dimensions of species' movement that are heavily influenced by uncertainty: knowledge about movement and relevance of movement to environmental decisions. Management decisions can be informed by their position in this knowledge‐relevance space. We then outline a framework to support decisions around (1) increasing understanding of the relevance of movement knowledge, (2) increasing robustness of decisions to uncertainties and (3) improving knowledge on species' movement. Our decision‐support framework provides guidance for managing movement‐related uncertainty in systematic conservation planning, agri‐environment schemes, habitat restoration and international biodiversity policy. It caters to different resource levels (time and funding) so that species' movement knowledge can be more effectively integrated into environmental decisions. [ABSTRACT FROM AUTHOR]