Jane Melville's research while affiliated with Monash University (Australia) and other places

The brown tree frog (Litoria ewingii) is a relatively widespread, commonly encountered pelodryadid frog from south-eastern Australia, known for its characteristic whistling call. The distribution of Litoria ewingii spans over more than 350,000 km2, encompassing a range of moist temperate habitats, and is fragmented by well-known biogeographic barriers. A preliminary analysis of mitochondrial DNA sequences revealed evidence for deep phylogenetic structure between some of these fragmented populations. In this study, we sought to re-evaluate the systematics and taxonomy of Litoria ewingii sensu lato by analysing variation in nuclear and mitochondrial DNA, adult morphology and male advertisement calls throughout the species’ range. Our analyses reveal two additional, deeply divergent and allopatric lineages in South Australia. We herein re-describe Litoria ewingii from Tasmania, southern New South Wales, Victoria and south-eastern South Australia, resurrect the name Litoria calliscelis for a species occurring in the Mount Lofty Ranges and Fleurieu Peninsula in South Australia, and describe a new species, Litoria sibilus sp. nov., endemic to Kangaroo Island.

Earless dragons (Tympanocryptis spp.) are found in most open dry environments across the Australian continent, with the 23 currently described species inhabiting a variety of ecological niches, from stony desert to tropical woodland or cracking clay savannahs. Recent species delimitation research using genetics (mtDNA, nDNA, SNPs) and geometric morphometric analyses of CT scans identified three genetic lineages of earless dragons that are yet to be described in Queensland, supporting the need for a taxonomic revision. Focussing on this geographic region, we use supporting evidence from a mitochondrial DNA (ND2) phylogeny, along with external morphological assessment, to undertake a taxonomic revision of Queensland earless dragons. Based on these data, we describe three new species of Tympanocryptis from the cracking clay grasslands of the Darling Riverine Basin, the Queensland Central Highlands, and the stony open eucalypt woodlands on the Einasleigh Uplands. The revision of these north-eastern Australian earless dragon species provides further taxonomic clarity within the Tympanocryptis genus.

Catastrophic megafires can increase extinction risks; identifying species priorities for management and policy support is critical for preparing and responding to future fires. However, empirical data on population loss and recovery post-fire, especially megafire, are limited and taxonomically biased. These gaps could be bridged if species' morphological, behavioural, ecological and life history traits indicated their fire responses. Using expert elicitation that estimated population changes following the 2019–20 Australian megafires for 142 terrestrial and aquatic animal species (from every vertebrate class, one invertebrate group), we examined whether expert estimates of fire-related mortality, mortality in the year post-fire, and recovery trajectories over 10 years/three generations post-fire, were related to species traits. Expert estimates for fire-related mortality were lower for species that could potentially flee or shelter from fire, and that associated with fire-prone habitats. Post-fire mortality estimates were linked to diet, diet specialisation, home range size, and susceptibility to introduced herbivores that damage or compete for resources. Longer-term population recovery estimates were linked to diet/habitat specialisation, susceptibility to introduced species; species with slower life histories and shorter subadult dispersal distances also had lower recovery estimates. Across animal groups, experts estimated that recovery was poorest for species with pre-fire population decline and more threatened conservation status. Sustained management is likely needed to recover species with habitat and diet specialisations, slower life histories, pre-existing declines and threatened conservation statuses. This study shows that traits could help inform management priorities before and after future megafires, but further empirical data on animal fire response is essential.

In many regions fire regimes are changing due to anthropogenic factors. Understanding the responses of species to fire can help to develop predictive models and inform fire management decisions. Spiders are a diverse and ubiquitous group and can offer important insights into the impacts of fire on invertebrates and whether these depend on environmental factors, phylogenetic history or functional traits. We conducted phylogenetic comparative analyses of data from studies investigating the impacts of fire on spiders. We investigated whether fire affects spider abundance or presence and whether ecologically relevant traits or site-specific factors influence species’ responses to fire. Although difficult to make broad generalizations about the impacts of fire due to variation in site- and fire-specific factors, we find evidence that short fire intervals may be a threat to some spiders, and that fire affects abundance and species compositions in forests relative to other vegetation types. Orb and sheet web weavers were also more likely to be absent after fire than ambush hunters, ground hunters and other hunters suggesting functional traits may affect responses. Finally, we show that analyses of published data can be used to detect broad-scale patterns and provide an alternative to traditional meta-analytical approaches.

Fire is a dominant process shaping the Australian landscape and in many regions the frequency and severity of wildfires are predicted to increase under climate change. The primary impact of fire on fauna is typically indirect through habitat change. In particular, in mesic forests different animal species are favoured at different times since fire as habitat complexity increases with vegetation recovery. However, this will not necessarily be the case in habitats with low complexity such as many of those occurring in arid and semi‐arid regions. Here, we investigate the relationship between fire history and ant diversity and composition in semi‐arid mallee of south‐eastern Australia. We surveyed ants at 11 sites in the Little Desert National Park and nearby private land that last burnt 0.5, 6 or 40 years ago. We found no relationship between time since fire and either ant diversity or composition, and this can be explained by a lack of relationship between time since fire and vegetation cover. Our findings contrast with those for mallee bird species, which show clear successional patterns following fire, but are likely to be typical of ground‐foraging fauna that lack specialized habitat requirements.

Context and challenges • Australia harbours a disproportionate share of global squamate diversity (lizards and snakes). The areas impacted by the 2019-20 wildfires comprise diverse squamate communities that include many threatened and narrowly distributed species. • The impact of fire on most Australian squamates is not well understood. Reptile populations are monitored less than any other vertebrate group, and many species have unresolved taxonomy. Main findings • Very few studies have considered the effects of fire on squamate mortality or how attributes of fire regimes affect squamates in areas impacted by the 2019-20 wildfires. • The habitat of 445 squamate species from 11 families was within the footprint of the 2019-20 wildfires, representing nearly 40% of Australia's described species. This included 29 species listed as threatened nationally or globally. • One species, Kate's leaf-tailed gecko (Saltuarius kateae), had its entire known (highly restricted) range burnt, but post-fire sampling indicated that the species persists and is breeding in the firegrounds. • Species in most need of monitoring and conservation following the 2019-20 wildfires are narrowly distributed species with moderate-to-high fire overlap and traits that make them vulnerable to fire and post-fire conditions. • Assessments of within-species diversity across 14 priority species identified 19 evolutionarily significant units and more than 18 management units. • Assessment of the on-ground effects of the 2019-20 wildfires is hampered by a lack of long-term monitoring and investment. There is an urgent need to break a cycle of chronic under-funding of reptile monitoring and conservation in Australia, particularly given the increasing prevalence of large, high severity wildfires.

Much attention is paid in conservation planning to the concept of a species, to ensure comparability across studies and regions when classifying taxa against criteria of endangerment and setting priorities for action. However, various jurisdictions now allow taxonomic ranks below the level of species and nontaxonomic intraspecific divisions to be factored into conservation planning-subspecies, key populations, evolutionarily significant units, or designatable units. Understanding patterns of genetic diversity and its distribution across the landscape is a key component in the identification of species boundaries and determination of substantial geographic structure within species. A total of 12,532 reliable polymorphic SNP loci were generated from 63 populations (286 individuals) covering the distribution of the Australian eastern three-lined skink, Bassiana duperreyi, to assess genetic population structure in the form of diagnosable lineages and their distribution across the landscape, with particular reference to the recent catastrophic bushfires of eastern Australia. Five well-supported diagnosable operational taxonomic units (OTUs) existed within B. duperreyi. Low levels of divergence of B. duperreyi between mainland Australia and Tasmania (no fixed allelic differences) support the notion of episodic exchange of alleles across Bass Strait (ca 60 m, 25 Kya) during periods of low sea level during the Upper Pleistocene rather than the much longer period of isolation (1.7 My) indicated by earlier studies using mitochondrial sequence variation. Our study provides foundational work for the detailed taxonomic re-evaluation of this species complex and the need for biodiversity assessment to include an examination of cryptic species and/or cryptic diversity below the level of species. Such information on lineage diversity within species and its distribution in the context of disturbance at a regional scale can be factored into conservation planning regardless of whether a decision is made to formally diagnose new species taxonomically and nomenclaturally.