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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]

Ploidy and species range size or threat status have been linked to variation in phenotypic and phenological seed and seedling traits, including seed size, germination rate (speed) and seedling stature. There is surprisingly little known about the ecological outcomes of relationships between ploidy, key plant traits and the drivers of range size. Here we determined whether ploidy and range size in Pomaderris , a genus of shrubs that includes many threatened species, are associated with variation in seed and seedling traits that might limit the regeneration performance of obligate seeders in fire-prone systems. We experimentally quantified seed dormancy and germination processes using fire-related heat treatments and evaluated seedling performance under drought stress. We also examined the association of seed size with other seed and seedling traits. Polyploids had bigger seeds, a faster germination rate and larger and taller seedlings than diploids. There was a lack of any clear relationship between range size and seed or seedling traits. The ploidy effects observed for many traits are likely to be indirect and associated with the underlying seed size differences. These findings indicate that there is a higher potential competitive advantage in polyploid than diploid Pomaderris during regeneration, a critical stage in the post-fire environment. This insight to the regeneration phase may need to be considered when planning and prioritising management of threatened species. [ABSTRACT FROM AUTHOR]

Pneumatopteris truncata is listed as Critically Endangered under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). The Australian population occurs only on Christmas Island where fewer than 50 mature individuals are known and population size fluctuates significantly across years. Ex situ conservation was prioritised as a critical response to insure against loss of the wild population. Spore from wild subpopulations was collected and germination and propagation techniques were trialled. This work has established ex situ spore and plant collections (more than 100 plants), developed protocols for germination and propagation of this species and identified priority future research for threatened fern species. [ABSTRACT FROM AUTHOR]

Polyploidy resulting from whole genome duplication is common in plants and is increasingly being recognised as a critical factor in conservation actions, particularly when within-species variation in ploidy exists. Pomaderris (Rhamnaceae), a genus of 70 species endemic to Australia and New Zealand, has many species listed as threatened and that are subject to conservation management but of unknown ploidy. To provide a better understanding of polyploidy in the genus we sampled 36 of 70 species of Pomaderris and used flow cytometry to establish genome sizes and infer ploidy. Additionally, to examine within-species variation, we screened 104 individuals of eight rare species subject to conservation management. We did not find evidence for infraspecific variation in ploidy, suggesting that from a cytological perspective, conspecific individuals from the screened populations do not need to be kept geographically separated in conservation management. There is, however, considerable variation among species, with genome sizes suggesting the occurrence of diploidy, triploidy, tetraploidy and hexaploidy. Finding several species to be triploid but capable of seed production, we then explored reproductive biology using the flow cytometric seed screen. Results suggested that triploid species produce seeds asexually, as previously reported for two New Zealand congeners. While asexual reproduction through apomixis is generally a means of odd-ploid taxa overcoming sterility, we found that more than half of examined diploids and tetraploids also produced seeds asexually. Asexual reproduction means genetic diversity is potentially low, and these results should therefore be considered in future conservation actions and seed sampling designs. [ABSTRACT FROM AUTHOR]

Substantial advances have been made in our understanding of the movement of species, including processes such as dispersal and migration. This knowledge has the potential to improve decisions about biodiversity policy and management, but it can be difficult for decision makers to readily access and integrate the growing body of movement science. This is, in part, due to a lack of synthesis of information that is sufficiently contextualized for a policy audience. Here, we identify key species movement concepts, including mechanisms, types, and moderators of movement, and review their relevance to (1) national biodiversity policies and strategies, (2) reserve planning and management, (3) threatened species protection and recovery, (4) impact and risk assessments, and (5) the prioritization of restoration actions. Based on the review, and considering recent developments in movement ecology, we provide a new framework that draws links between aspects of movement knowledge that are likely the most relevant to each biodiversity policy category. Our framework also shows that there is substantial opportunity for collaboration between researchers and government decision makers in the use of movement science to promote positive biodiversity outcomes. [ABSTRACT FROM AUTHOR]