South-western Western Australia Research Articles

Evaluating the risk to Australia’s flora from Phytophthora cinnamomi

Context Phytophthora cinnamomi Rands is a destructive pathogen of Australian native vegetation, often causing permanent damage to ecosystems and threatening the survival of rare, susceptible species. Despite that, much information about the effects of P. cinnamomi on plant species remains unpublished and the risk of extinction to most species is unknown. Aims We aimed to classify the risk of extinction from P. cinnamomi to Australian native plants. Methods We used available data and personal knowledge about P. cinnamomi effects on plants, spatial data on plant species distribution and habitat suitability of P. cinnamomi to assign an extinction-risk category of low, moderate, high or very high. Key results There are currently 65 plant species at a very high risk of extinction in Australia as a result of P. cinnamomi infection. The genera Andersonia, Banksia, Darwinia, Daviesia, Epacris, Gastrolobium, Grevillea, Hibbertia, Isopogon, Lambertia, Latrobea, Leucopogon, Phebalium and Styphelia have multiple species at a very high risk of extinction, most of which occur in south-western Western Australia. Conclusions The available data confirmed the high risk to the Australian flora from P. cinnamomi and identified species in plant families not previously known to be affected, highlighting data gaps (e.g. lack of knowledge about effects and risk in orchids and grasses). Implications Much more work is required to fully understand the risk from P. cinnamomi (and other Phytophthora species) to the Australian flora.

Hemigenia glaucissima (Lamiaceae), a rare new species from south-west Western Australia

Hemigenia glaucissima, a rare species from south-western Western Australia, is here described with associated photographic images and distribution map. The new species is restricted to mallee eucalypt woodland in the south-eastern wheatbelt region of the state. Currently, it is only known from two nearby populations that were first collected during botanical surveys for a mining project near Parker Range.

<i>Corrigendum to</i>: The role of grass-tree <i>Xanthorrhoea semiplana</i> (Asphodelaceae) canopies in temperature regulation and waterproofing for ground-dwelling wildlife

<sec> Context Birds appear to be better suited than mammals or reptiles to adapt to fast-changing landscapes because of their greater mobility; however, the behavioural effects of urbanisation on birds in Australia remain broadly unexplored. </sec> <sec> Aims This study aimed to investigate the effects of urbanisation on behavioural responses exhibited by a common and widespread meliphagid, the bandiny or New Holland honeyeater (<i>Phylidonyris novaehollandiae</i>) while undergoing standard bird banding processes. </sec> <sec> Methods Five non-invasive techniques (alarm calling, wriggling, biting, breathing rate, and tonic immobility) were explored for efficacy in identifying underlying differences in distress arising from mist-netting at urban and exurban localities in southwestern Western Australia. </sec> <sec> Key results Breathing rate was the most important variable for identifying differences in post-capture distress response. The breathing rate of urban bandiny following capture was lower than those of exurban areas. All other parameters proved suboptimal for detecting differential behavioural responses to handling between urban and exurban populations, despite having been successfully used in other international studies. </sec> <sec> Conclusions We suggest that urban honeyeaters exhibit lower mean breathing rates due to chronic overstimulation in response to urban lifestyles and are not able to further elevate this behaviour in response to stressful stimuli. The failure of other approaches explored highlights the need to apply ecosystem-appropriate methods for investigating urbanisation within an Australian context. </sec> <sec> Implications Our results suggest that behavioural approaches to quantifying avian stress developed internationally require additional consideration when applied to the ecosystems of Australia, whose birds are evolved to accommodate a different regime of seasonality that has shaped them behaviourally and morphologically. </sec>

Banksia (Proteaceae) contains less phylogenetic diversity than expected in Southwestern Australia

AbstractBanksia L.f., an iconic genus of the Proteaceae, is endemic to Australia, with its highest species richness and phylogenetic diversity (PD) in southwestern Western Australia. Analysis of the phylogenetic component of richness and endemism uncovered important patterns of Banksia evolutionary history that are not seen at the species level. We found that Banksia is significantly phylogenetically clustered in this region, likely due to recent evolutionary radiations. We also found significant concentrations of phylogenetic endemism in this region, both neoendemism (short, range‐restricted evolutionary branches) and paleoendemism (long, range‐restricted evolutionary branches). There is a striking northwest to southeast divide in phyloturnover in southwestern Western Australia. The majority of the variation in turnover patterns can be explained by environmental factors, with climate representing the largest covariate. This study adds to the growing body of evidence that indicates the importance of integrating phylogenetic and biodiversity data to inform conservation planning.

Phylogeny and morphology of the Australian snake genus Neelaps Günther, 1863 (Squamata: Elapidae), with resurrection of Narophis Worrell, 1961

Recent phylogenetic studies have shown that the affinities of the two currently recognised species of Neelaps Günther, 1863, Neelaps bimaculatus (Duméril, Bibron & Duméril, 1854) and Neelaps calonotos (Duméril, Bibron & Duméril, 1854), are unresolved. Here we provide an expanded molecular phylogeny and new morphology data to clarify generic boundaries. We did not find support for monophyly of Neelaps, confirming previous evidence. As a consequence, we allocate bimaculatus to the available synonym Narophis Worrell, 1961 and restrict calonotos to Neelaps, forming two monotypic genera. We redescribe both species under this revised classification. Neelaps calonotos adds to the list of endemic monotypic vertebrates in southwestern Western Australia, recognised globally as a biodiversity hotspot, and we comment on the name spelling, type specimens and conservation status of this distinctive species.

Two new Western Australian species related to Hibbertia priceana (Dilleniaceae)

Hibbertia priceana is a rare species found in two localised areas in southern south-western Western Australia, near Ongerup and in the vicinity of Wickepin and Harrismith. Two new species that are morphologically similar to H. priceana but are disjunct and distinct from it are described in this paper. Hibbertia hapalophylla is a new, potentially geographically restricted and rare species first collected during botanical surveys for a mining project near Mount Holland in the Western Australian Goldfields. It was initially collected from, and only known from, disturbed areas on an active mine site, but larger populations were subsequently discovered on a nearby sandplain, from where is was likely introduced to the mine site on sand transported for construction purposes. The second new species, Hibbertia remanens, appears to be restricted to small areas of remnant vegetation near Cunderdin and Kellerberrin in the Western Australian wheatbelt. The three species differ mainly in their leaf shapes in section, with H. priceana having flat leaves with the abaxial lamina fully exposed, H. remanens having recurved leaf margins with the abaxial shallowly grooved either side of the midrib, and H. hapalophylla having strongly revolute margins with the abaxial lamina surface concealed within lacunae formed between the margins and midrib.

A new spider species of the genus Proshermacha (Mygalomorphae: Anamidae) from the Coolgardie and Murchison bioregions of Western Australia, collected on a Bush Blitz expedition

The open-holed trapdoor spider genus Proshermacha Simon, 1908 (Anamidae) currently contains ten species. The genus is known to occur from south-western Western Australia, through southern South Australia and into western Victoria. Here, we describe the first species from semi-arid Western Australia, from Credo Station Reserve and surroundings. Several specimens of this species, including the holotype, were collected on a Bush Blitz expedition to Credo Station Reserve, in 2011.

Hibbertia aplacophylla (Dilleniaceae), a new species from south-western Western Australia segregated from H. notibractea

Hibbertia aplacophylla K.R.Thiele sp. nov. is here segregated from H. notibractea J.R.Wheeler. It comprises plants from a disjunct population on the far south coast of Western Australia that differ most significantly from H. notibractea in having leaves with a distinct midrib and recurved margins (cf. flat with neither midrib nor recurved margins), sepals that are quite glabrous (cf. ciliate-margined), and anthers held erect at the ends of the fused filaments (cf. deflexed).

Regional significance of historical trends and step changes in Australian streamflow

Abstract. The Hydrologic Reference Stations is a network of 467 high-quality streamflow gauging stations across Australia that is developed and maintained by the Bureau of Meteorology as part of an ongoing responsibility under the Water Act 2007. The main objectives of the service are to observe and detect climate-driven changes in observed streamflow and to provide a quality-controlled dataset for research. We investigate trends and step changes in streamflow across Australia in data from all 467 streamflow gauging stations. Data from 30 to 69 years in duration ending in February 2019 were examined. We analysed data in terms of water-year totals and for the four seasons. The commencement of the water year varies across the country – mainly from February–March in the south to September–October in the north. We summarized our findings for each of the 12 drainage divisions defined by Australian Hydrological Geospatial Fabric (Geofabric) and for continental Australia as a whole. We used statistical tests to detect and analyse linear and step changes in seasonal and annual streamflow. Monotonic trends were detected using modified Mann–Kendall (MK) tests, including a variance correction approach (MK3), a block bootstrap approach (MK3bs) and a long-term persistence approach (MK4). A nonparametric Pettitt test was used for step-change detection and identification. The regional significance of these changes at the drainage division scale was analysed and synthesized using a Walker test. The Murray–Darling Basin, home to Australia's largest river system, showed statistically significant decreasing trends for the region with respect to the annual total and all four seasons. Drainage divisions in New South Wales, Victoria and Tasmania showed significant annual and seasonal decreasing trends. Similar results were found in south-western Western Australia, South Australia and north-eastern Queensland. There was no significant spatial pattern observed in central nor mid-west Western Australia, with one possible explanation for this being the sparse density of streamflow stations and/or the length of the datasets available. Only the Tanami–Timor Sea Coast drainage division in northern Australia showed increasing trends and step changes in annual and seasonal streamflow that were regionally significant. Most of the step changes occurred during 1970–1999. In the south-eastern part of Australia, the majority of the step changes occurred in the 1990s, before the onset of the “Millennium Drought”. Long-term monotonic trends in observed streamflow and its regional significance are consistent with observed changes in climate experienced across Australia. The findings of this study will assist water managers with long-term infrastructure planning and management of water resources under climate variability and change across Australia.

Neolucia bollami Eastwood, Braby & Graham, sp. nov. (Lepidoptera: Lycaenidae): speciation of a new allochronic cryptic butterfly from south-western Western Australia

South-western Western Australia is a global biodiversity hotspot renowned for exceptional diversity of plants and animals. The evolutionary processes that have generated this high biodiversity are not always clear, particularly for invertebrates, yet the area supports a very large number of endemic species that have diversified in situ. We use an integrative taxonomic approach based on adult and immature morphology, ecology, behaviour and molecular data to investigate the taxonomic status of a sympatric but seasonally isolated form (Neolucia agricola occidens Waterhouse & Lyell, 1914 form ‘Julimar’) of the polyommatine butterfly Neolucia agricola (Westwood, 1851) in south-western Western Australia. Our molecular dataset comprised 112 samples representing all Neolucia Waterhouse & Turner, 1905 species (100 COI 5′ sequences, 658 bp, plus 12 COI 3′, tRNA Leu, COII and EF1-α sequences, 3303 bp). Maximum likelihood phylogenetic analysis of the combined dataset recovered form ‘Julimar’ and N. agricola as reciprocally monophyletic, with a mean uncorrected ‘p’ pairwise divergence of 5.77% for the ‘barcode’ region of COI. Based on this and other evidence we recognise form ‘Julimar’ as a new species, Neolucia bollami Eastwood, Braby & Graham, sp. nov., sister to N. agricola and endemic to south-western Western Australia. As a result of these findings, we evaluated the evolutionary history of the two Neolucia species in WA and the processes that may have contributed to the diversification in sympatry or allopatry. We conclude that the multiple effect traits associated with a host shift, including host fidelity and temporal divergence, played an important role in the diversification process and in maintaining the reproductive integrity of the nascent allochronic species. ZooBank: urn:lsid:zoobank.org:act:53D9AD14-9694-4B5E-889C-A8D533E7F57D

Fossombronia bracchia Cargill (Fossombroniaceae, Marchantiophyta), a new species from Western Australia

The new species, Fossombronia bracchia, from Lesueur National Park, an area of high vascular plant endemism and species richness in southwestern Western Australia, is described and illustrated; a distribution map is provided. The new species has strong morphological similarities to the South African species F. tumida.

Soil moisture and temperature drive emergence delays associated with fire seasonality in eucalypt forests

Abstract Many ecosystems are well adapted to fire, although the impacts of fire seasonality and its effect on post-fire recruitment are less well understood. Late summer or autumn fires within eucalypt forests with a Mediterranean-type climate allow for seedling emergence during the cooler and wetter seasons. The emergence and survival after spring fires may be impacted by higher soil temperatures and water stress, delaying recruitment until the subsequent winter period. During this delay, seeds may be exposed to predation and decay, which reduce the viable seed bank. This study examines post-fire recruitment dynamics in a eucalypt forest ecosystem (Northern Jarrah Forest (NJF) of southwestern Western Australia) and whether it may be vulnerable to human-induced changes to fire season. Here, we compare in situ post-fire seedling emergence patterns between autumn and spring burns and account for a potential ecological mechanism driving seasonal differences in emergence by determining the thermal germination requirements of seeds for 15 common species from the NJF. Our results demonstrate that 93% of species had thermal optima between 10°C and 20°C, analogous with soil temperatures measured during the germination window (late April to October). Concurrent in situ post-fire emergence was highest 144 days after an autumn (seasonal) fire, followed by a 10–72% decline. In contrast, there was no emergence within the first 200 days following a spring (aseasonal) fire. We conclude that aseasonal fire in the NJF can lead to a complete delay in recruitment in the first season post-fire, resulting in a lower inter-fire growth period and increasing the potential for further reductions in recruitment through seed predation and decay. The study suggests that aseasonal fire has an immediate and significant impact on initial recruitment in the NJF, but further research is required to determine any longer-term effects of this delay and its implications for fire management in southwestern Western Australia.

Quokkaraneus, a new monotypic genus of Australian orb-weaving spider (Araneae, Araneidae)

A new monotypic Australian genus in the orb-weaving spider family Araneidae Clerck, 1757 is described, Quokkaraneus gen. nov., with Q. necopinus (Keyserling, 1887) comb. nov. as type species. Morphologically the new genus has affinities with the Australasian clade informally termed 'backobourkiines', due to the presence of a single patellar macroseta and the median apophysis forming an arch over the radix in the male pedipalp. It distinctly differs from other genera of this clade by somatic characters, such as a unique white cephalic and/or thoracic area and abdomen. Some genitalic characters are also diagnostic amongst the backobourkiines, such as a C-shaped median apophysis with pointed tip, triangular terminal apophysis and prominent concave conductor in males, and a very broad female epigyne scape. Quokkaraneus necopinus comb. nov. occurs in southern Australia, from western Victoria to south-western Western Australia.

A review of monotreme (Monotremata) evolution

Advances in dating and systematics have prompted a revision of monotreme evolution to refine the timing of adaptative trends affecting body size and craniodental morphology. The oldest known monotreme, Teinolophos trusleri, is restricted to uppermost Barremian deposits of the Strzelecki Group in Victoria, Australia. Its body mass is estimated at ∼40 g, making it the smallest known monotreme. Teinolophos trusleri likely possessed an electro-sensitive and/or mechano-sensitive ‘bill’ or ‘beak’, which we suggest evolved for insectivory in seasonally dark Early Cretaceous polar forests. During the early Albian–mid-Cenomanian, monotremes diversified in Australia and evolved body masses greater than 4 kg, becoming amongst the largest Mesozoic mammals. A gap of 35 million years subsequently separates the youngest Mesozoic monotremes from the oldest Cenozoic monotreme, Monotrematum sudamericanum, which is a Paleocene stem ornithorhynchid from southern South America. We also hypothesize that tachyglossids originated in Melanesia, perhaps on the emergent Vogelkop landmass, and then dispersed to Australia during the Pliocene-Pleistocene. Finally, we present a classification of Monotremata to include five families—Teinolophidae fam. nov., Kollikodontidae, Steropodontidae, Ornithorhynchidae, and Tachyglossidae. We also propose a new genus, Murrayglossus gen. nov. for a gigantic Pleistocene echidna from southwestern Western Australia. http://zoobank.org/urn:lsid:zoobank.org:pub:E39E2644-DADD-49F4-B2B7-47A25C072B07 Timothy F. Flannery [tim.flannery@textpublishing.com.au], Kristofer M. Helgen [Kris.Helgen@Australian.Museum], Australian Museum, 1 William St Sydney 2000, Australia; Thomas H. Rich [trich@museum.vic.gov.au], Tim Ziegler [tziegler@museum.vic.gov.au], Museums Victoria, PO Box 666, Melbourne, Victoria 3001, Australia; Patricia Vickers-Rich [pat.rich@monash.edu; prich@swin.edu.au], School of Earth, Atmosphere and Environment, Monash University, Victoria 3800, Australia; Swinburne University of Science and Technology, Department of Chemistry and Biotechnology, Hawthorn, Victoria 3122, Australia; Elizabeth Grace Veatch [elizabeth.veatch@gmail.com], National Museum of Natural History, Smithsonian Institution, Washington, DC 20013, USA.

Distress responses during handling in urban and exurban bandiny, the New Holland honeyeater (Phylidonyris novaehollandiae), in southwestern Western Australia

Context Birds appear to be better suited than mammals or reptiles to adapt to fast-changing landscapes because of their greater mobility; however, the behavioural effects of urbanisation on birds in Australia remain broadly unexplored. Aims This study aimed to investigate the effects of urbanisation on behavioural responses exhibited by a common and widespread meliphagid, the bandiny or New Holland honeyeater (Phylidonyris novaehollandiae) while undergoing standard bird banding processes. Methods Five non-invasive techniques (alarm calling, wriggling, biting, breathing rate, and tonic immobility) were explored for efficacy in identifying underlying differences in distress arising from mist-netting at urban and exurban localities in southwestern Western Australia. Key results Breathing rate was the most important variable for identifying differences in post-capture distress response. The breathing rate of urban bandiny following capture was lower than those of exurban areas. All other parameters proved suboptimal for detecting differential behavioural responses to handling between urban and exurban populations, despite having been successfully used in other international studies. Conclusions We suggest that urban honeyeaters exhibit lower mean breathing rates due to chronic overstimulation in response to urban lifestyles and are not able to further elevate this behaviour in response to stressful stimuli. The failure of other approaches explored highlights the need to apply ecosystem-appropriate methods for investigating urbanisation within an Australian context. Implications Our results suggest that behavioural approaches to quantifying avian stress developed internationally require additional consideration when applied to the ecosystems of Australia, whose birds are evolved to accommodate a different regime of seasonality that has shaped them behaviourally and morphologically.

Rainfall Stable Water Isotope Variability in Coastal Southwestern Western Australia and Its Relationship to Climate on Multiple Timescales

AbstractThe factors driving variability in rainfall stable water isotopes (specifically δ18O and deuterium excess, d = δ2H − 8 δ18O) were studied in a 13‐year data set of daily rainfall samples from coastal southwestern Western Australia (SWWA). Backwards dispersion modeling, automatic synoptic type classification, and a statistical model were used to establish causes of variability on a daily scale; and predictions from the model were aggregated to longer temporal scales to discover the cause of variability on multiple timescales. Factors differ between δ18O and d and differ according to temporal scale. Rainfall intensity, both at the observation site and upwind, was most important for determining δ18O and this relationship was robust across all time scales (daily, seasonal, and interannual) as well as generalizing to a second observation site. The sensitivity of δ18O to rainfall intensity makes annual mean values particularly sensitive to the year's largest events. Projecting the rainfall intensity relationship back through ∼100 years of precipitation observations can explain ∼–0.4‰ shifts in rainfall δ18O. Twentieth century speleothem records from the region exhibit signals of a similar magnitude, indicating that rainfall intensity should be taken into account during the interpretation of regional climate archives. For d, humidity during evaporation from the ocean was the most important driver of variability at the daily scale, as well as explaining the seasonal cycle, but source humidity failed to explain the longer‐term interannual variability.

Wavelet geographically weighted regression for spectroscopic modelling of soil properties

Soil properties, such as organic carbon, pH and clay content, are critical indicators of ecosystem function. Visible–near infrared (vis–NIR) reflectance spectroscopy has been widely used to cost-efficiently estimate such soil properties. Multivariate modelling, such as partial least squares regression (PLSR), and machine learning are the most common methods for modelling soil properties with spectra. Often, such models do not account for the multiresolution information presented in the vis–NIR signal, or the spatial variation in the data. To address these potential shortcomings, we used wavelets to decompose the vis–NIR spectra of 226 soils from agricultural and forested regions in south-western Western Australia and developed a wavelet geographically weighted regression (WGWR) for estimating soil organic carbon content, clay content and pH. To evaluate the WGWR models, we compared them to linear models derived with multiresolution data from a wavelet decomposition (WLR) and PLSR without multiresolution information. Overall, validation of the WGWR models produced more accurate estimates of the soil properties than WLR and PLSR. Around 3.5–49.1% of the improvement in the estimates was due to the multiresolution analysis and 1.0–5.2% due to the integration of spatial information in the modelling. The WGWR improves the modelling of soil properties with spectra.

A new bat species from southwestern Western Australia, previously assigned to Gould’s Long-eared Bat Nyctophilus gouldi Tomes, 1858

A distributional isolate in southwestern Western Australia previously assigned to Gould’s Long-eared Bat Nyctophilus gouldi Tomes, 1858 is demonstrated to be a distinct and previously unnamed cryptic species, based on a lack of monophyly with eastern populations and substantial DNA sequence divergence (5.0 %) at the mitochondrial gene COI. Morphologically both species are alike and overlap in all measured characters but differ in braincase shape. The new species has one of the most restricted geographic ranges of any Australian Vespertilionidae and aspects of its ecology make it vulnerable to human impacts.

Interdecadal changes in Southern Hemisphere winter explosive storms and Southern Australian rainfall

Interdecadal changes, over the last seventy years, in winter synoptic weather systems that grow and decay in the extratropical storm tracks of the Southern Hemisphere are investigated. The statistics of the intensity of growing and decaying eddies, and their preferred structures and growth rates, are determined from 6-hourly lower-tropospheric reanalysis data for high-pass filtered (period less than 4 days) and band-pass filtered (period between 4 and 8 days) disturbances. A new data-driven methodology is used in which the perturbations are spectrally analysed in both space and time, their growth rates are calculated and statistics are accumulated for growing and decaying instabilities. Rainfall variability in Southern Australia is found to be closely related to the changing statistics of weather system intensity and to interannual and decadal variability in indices or predictors that characterize local, hemispheric or global aspects of the atmospheric circulation. In investigations into the mid-1970s drying of southwestern Western Australia, the Australian Millennium Drought and Southern Australian rainfall anomalies of the early twenty-first century it is found that decadal changes in rainfall are most related to the intensity of the fast growing weather systems. Two new indices, the Subtropical Atmospheric Jet (SAJ) index and the Southern Ocean Regional Dipole (SORD) index, are introduced and shown to have some skill in characterizing aspects of Southern Australian winter rainfall variability particularly on decadal timescales.

The Asian fish tapeworm (Schyzocotyle acheilognathi) discovered in Western Australia may pose a threat to the health of endemic native fishes

AbstractThe Asian fish tapeworm (Schyzocotyle acheilognathi) is an important fish parasite with a wide host range that infects over 300 species of fish worldwide.Schyzocotyle acheilognathihas been reported from eastern coastal areas of Australia, but has not been previously reported in Western Australia (WA). During a control program for invasive freshwater fishes in south-western WA, a region with a unique and highly endangered freshwater fish fauna, tapeworms identified asS.acheilognathifrom their distinctive scolex morphology were found at a prevalence of 3.3% in goldfish (Carassius auratus), 37.0% in koi carp (Cyprinus carpio haematopterus) and 65.0% in eastern gambusia (Gambusia holbrooki) in a small suburban lake to the north of Perth. For molecular confirmation, the 18S ribosomal RNA gene was targeted at hypervariable V4 region. Koi carp isolates were 100% identical toS.acheilognathiisolated from varying hosts, including the red shiner (Cyprinella lutrensis) and a human sample. Sequences obtained from two eastern gambusia were identified asS.acheilognathi, but formed a discrete cluster and may represent a novel genotype. Isolates from two other eastern gambusia and two goldfish formed a distinct clade with only 91.9% similarity to previously sequenced isolates ofS.acheilognathi. This emphasizes the importance of molecular identification methods in addition to morphological identification. The presence and potential for transmission of these parasites in south-western WA may threaten the health of native fishes, which are immunologically naïve to this introduced parasite. Immediate control or containment measures should be implemented to halt the spread of these parasites.