Barrow Island Research Articles

Environmental determination of body size in mammals: Rethinking ‘island dwarfism’ in the golden bandicoot

AbstractThere are several cases of insular animal species exhibiting dramatic differences in body size when compared with mainland counterparts. Such pronounced morphological changes can arise from divergent selection via differing resource availability, competition or predation pressure. Past studies have not been able to demonstrate a reversal of these morphological changes when populations are removed from their island situation. This study examines the body size response of populations of the Barrow Island ‘dwarf’ subspecies of golden bandicoot (Isoodon auratus barrowensis: Ramsay, 1887) following translocation to an island and mainland site within their former range. Skeletal and mass measurements, body condition and fecundity of released animals and their offspring were compared to data from the source population. When comparing bandicoots born at translocation sites to source populations, males were significantly larger in skeletal size and mass, females were also significantly larger and exhibited higher reproductive output (number, frequency and average mass of pouch young). These effects occurred in a gradient according to environmental conditions, where animals were smallest and least productive at the densely populated source site, larger and more productive on a nearby island, and largest and most productive at a mainland site with some nutritional supplementation. These changes in skeletal size, mass and fecundity took place in the first 1–4 generations (18 months post‐release), suggesting that the response is not explained by natural selection. We posit that the small size of golden bandicoots on Barrow Island (315.8 ± 4.2 g, this study, cf 569.4 ± 19.3 g, mainland) is not a genotypic response to selective pressures, but rather a reversible phenotypic response to more favourable environmental conditions. A reduction in competitive pressures appeared to allow bandicoots to grow to a larger size and mass, and allow greater reproductive output. Ecological processes relating to resource limitation appear to drive ‘island dwarfism’ in I. auratus, and may apply to other insular species with morphological differentiation.

Physical sedimentary controls on subtropical coastal and shelf sedimentary systems: Initial application in conceptual models and computer visualizations to support archaeology

AbstractAdvances in digital spatial analysis and 3D photorealistic modeling offer the potential to create virtual interpretations of the now inundated landscapes of NW Australia. While this provides a useful template for potential late Pleistocene and early Holocene coastal occupation on the shelf, we stress the importance of understanding sediment dynamics as a primary control for terrain modelling, particularly at the scale of human ecosystem dynamics. We briefly review six major drivers of change upon tropical and semi‐tropical continental shelves and coastlines, and some of the typical coastal geomorphologies associated with each. We then hypothesize how these drivers might have varied on the NW Shelf of Australia since 65 ka, and then apply the logic to the Barrow Island region, to form some “end‐member” visualizations of coastal change in the early Holocene. The visualizations indicate a high degree of variability in coastal morphology, particularly through the post‐glacial period, which is likely to have radically changed the capacity of the coastline to provide resources for human use during that period. Hence, rather than considering any single visualization as being absolute, end‐member visualizations should be used to generate testable hypotheses that are reviewed repeatedly in the light of new physical, environmental, and archaeological information.

The effects of suspended sediment on coral reef fish assemblages and feeding guilds of north-west Australia

This study was funded by the Chevron-operated Wheatstone Project's State Environmental Offsets Program and administered by the Department of Biodiversity, Conservation and Attractions. The Wheatstone Project is a joint venture between Australian subsidiaries of Chevron, Kuwait Foreign Petroleum Exploration Company (KUFPEC), Woodside Petroleum Limited and Kyushu Electric Power Company, together with PE Wheatstone Pty Ltd (part owned by TEPCO). Funding support was also received from the Gorgon Barrow Island Net Conservation Benefits Fund, which is administered by the Department of Biodiversity, Conservation and Attractions. Thank you to Helen Chedzey and Mark Broomhall from the Remote Sensing and Satellite Research Group at Curtin University for generating and providing the remotely sensed total suspended solids data for this study.

Multiple molecular markers reinforce the systematic framework of unique Australian cave fishes (Milyeringa : Gobioidei)

Australia was once thought to be a biodiversity desert when considering the subterranean world; however, recent work has revealed a fascinating collection of cave creatures, many with surprising biogeographic histories. This has especially been so in the karstic regions of north-western Australia (Cape Range peninsula, Barrow Island, Pilbara), which is home not only to a diverse collection of subterranean invertebrates, but also to the continent’s only known underworld-adapted vertebrates, which includes the cave fish in the genus Milyeringa. These cave gudgeons have recently been in a state of taxonomic flux, with species being both split and lumped, but this was done with limited data (incomplete geographic sampling and no nuclear DNA sequence data). Therefore, we have revisited the systematic status of Milyeringa in a total-evidence molecular approach by integrating all existing data (mitochondrial, allozymes) with new DNA sequences from nuclear and mitochondrial loci and new multilocus allozyme data. Our conclusion, that there are two species, matches the most recent taxonomic treatment, with Milyeringa veritas present on both the eastern and western sides of the Cape Range peninsula, and Milyeringa justitia on Barrow Island. This has implications for future research in the linked fields of biogeography and conservation.

A Lean Sigma Approach to Well Stimulation on Barrow Island, Australia

Summary Barrow Island (BWI), 56 km from the coast of Western Australia (WA), is home to several mature reservoirs that have produced oil since 1965. The main reservoir is the Windalia Sandstone, and it has been waterflooded since 1967, whereas all the other reservoirs are under primary depletion. Because of the maturity of the asset, it is economically critical to continue to maximize oil-production rates from the 430 online, artificially lifted wells. It is not an easy task to rank well-stimulation opportunities and streamline their execution. To this end, the BWI Subsurface Team applied the Lean Sigma processes to identify opportunities, increase efficiency, and reduce waste relating to well stimulation and well-performance improvement. The Lean Sigma methodology is a combination of Lean Production and Six Sigma, which are methods used to minimize waste and reduce variability, respectively. The methods are used globally in many industries, especially those involved in manufacturing. In this asset, we applied the processes specifically to well-performance improvement through stimulation and other means. The team broadly focused on categorizing opportunities in both production and injection wells and ranking them—specifically, descaling wells, matrix acidizing, sucker-rod optimization, reperforating, and proactive workovers. The process for performing each type of job was mapped, and bottlenecks in each process were isolated. Upon entering the “control” phase, several opportunities had been identified and put in place. Substantial improvements were made to the procurement, logistics, and storage of hydrochloric acid (HCl) and associated additives, enabling quicker execution of stimulation work. A new program was also developed to stimulate wells that had recently failed and were already awaiting workover (AWO), which reduced costs. A database containing the stimulation opportunities available at each individual well assisted with this process. The project resulted in the stimulation of several wells in the asset, with sizable oil-rate increases in each. This case study will extend the information available within the oil-industry literature regarding the application of Lean Sigma to producing assets. It will assist other operators when evaluating well-stimulation opportunities in their fields. Technical information will be shared regarding feasibility studies (laboratory-compatibility work and well-transient-testing results) for acid stimulation and steps that can be taken to streamline the execution of such work. Some insights will also be shared regarding the most-efficient manner to plan rig work regarding stimulation workovers.

Historical perspectives on the mangroves of Kakadu National Park

Mangroves are a major ecosystem within Kakadu National Park in Australia’s Northern Territory, providing coastal protection, high biodiversity and an important resource for Aboriginal people. In the late Holocene (from c. 6000 before present), mangroves occupied much of the estuarine and coastal plains, but their range has subsequently contracted to the main river systems (the West Alligator, South Alligator and East Alligator Rivers, and the Wildman River), tributary creeks and offshore islands (Field and Barrow Islands). On the basis of maps of mangrove extent generated from aerial photography (1950, 1975, 1984 and 1991), compact airborne spectrographic imagery (CASI; 2002), light detection and ranging (LIDAR; 2011) and RapidEye data (2014 onward), changes in net area have been minor but significant redistribution has occurred, with this being attributed to both inland intrusion and seaward colonisation of mangroves. The greatest area changes have been associated with lower-stature mangroves dominated by Avicennia marina and Sonneratia alba, as determined from these datasets. Aerial surveys, conducted using a remote piloted aircraft (RPA) and fixed wing aircraft in September 2016, showed dieback of mangroves, with spaceborne RapidEye observations suggesting this occurred between late 2015 and 2016 and at the same time as the extensive mangrove losses reported in the Gulf of Carpentaria. Given the recent dieback and the associated need to better monitor and protect mangroves and proximal ecosystems in the World Heritage- and Ramsar-listed Kakadu National Park, the study recommends the development and implementation of a robust and long-term monitoring system that better utilises existing and ongoing earth observation and ground data, and is supported by a national approach.

Salticidae (Arachnida: Araneae) inhabiting islands off Australia re‐visited

AbstractThe jumping spider fauna of 99 Australian islands of coral, volcanic, continental and mixed origin was investigated in terms of taxonomic diversity, origin (source), dispersal and habitat preferences. A total of 110 taxa were recorded; with 18 taxa found on at least five islands. Barrow, Horn, Fitzroy, Fraser, Murray and Moa Islands appeared the most diverse, each with at least 10 species. On all islands combined the most speciose genera were Cytaea (16 species), Cosmophasis (8), ‘Lycidas’/Jotus (5), Simaetha (4) and Holoplatys (4). The island faunas appeared to be a less diverse version of the mainland (mostly eastern coast) and showed no evidence of local radiation and endemism.

50,000 years of archaeological site stratigraphy and micromorphology in Boodie Cave, Barrow Island, Western Australia

This study explores the application of soil micromorphological and automated scanning electron microscopy mineralogical analysis to characterise lithological boundaries and site formation history from an archaeological cave site on Barrow Island, northwestern Australia. The high-resolution characterisation is used to document the changing depositional context within Boodie Cave from the earliest period of occupation around 50kyBP through to when transgressing seas isolated the island around 7kyBP. Comparisons are made between excavations at the front of the cave — where stratigraphic integrity is high and a thicker, more comprehensive early Holocene sequence is preserved, with excavations inside the cave — where stratigraphic integrity is lower but an older Pleistocene record is preserved. The combination of these depositional scenarios provides a complete stratigraphic sequence for Boodie Cave, with depositional contacts defined at macro-, meso- and micro-scale levels. These contacts include erosive surfaces and trampled (ground) surfaces, such as the upper interface of SU5 and SU4. Based on the mineralogical and textural variations (microfacies) preserved within each unit, the vertical mixing zone is estimated to be between 1 and 5cm. This reworking has not affected the general sequence of sedimentological (including grain size and mineralogy) and macro-cultural changes, which record an increasingly marine-dominated assemblage as the coastline encroaches. The integration of microscopic observations with anthracological, archaeomalacological, zooarchaeological and lithic analyses provides a more dynamic and comprehensive dialogue for interpreting the formation history of Boodie Cave and likely other early occupation sites from northern Australia.

Rickettsia gravesii sp. nov.: a novel spotted fever group rickettsia in Western Australian Amblyomma triguttatum triguttatum ticks.

A rickettsial organism harboured by Amblyomma triguttatum ticks on Barrow Island, Western Australia, was discovered after reports of possible rickettsiosis among local workers. Subsequent isolation of this rickettsia (strain BWI-1) in cell culture and analysis of its phylogenetic, genotypic and phenotypic relationships with type strains of Rickettsia species with standing in nomenclature suggested that it was sufficiently divergent to warrant its classification as a new species. Multiple gene comparison of strain BWI-1 revealed degrees of sequence similarity with Rickettsia raoultii, its closest relative, of 99.58, 98.89, 97.03, 96.93 and 95.73 % for the 16S rRNA, citrate synthase, ompA, ompB and sca4 genes, respectively. Serotyping in mice also demonstrated that strain BWI-1T was distinct from Rickettsia raoultii. Thus, we propose the naming of a new species, Rickettsia gravesii sp. nov., based on its novel genotypic and phenotypic characteristics. Strain BWI-1T was deposited in the ATCC, CSUR and ARRL collections under reference numbers VR-1664, CSUR R172 and RGBWI-1, respectively.

Natural Conservation of Isolated Islands: Focusing on Seabed Mining around Barrow Island of Western Australia

Natural Conservation of Isolated Islands: Focusing on Seabed Mining around Barrow Island of Western Australia

Accounting for environmental uncertainty in the management of dredging impacts using probabilistic dose–response relationships and thresholds

Abstract Dredging and related activities are common across nearshore marine environments, potentially threatening nearby ecosystems. Regulatory frameworks are essential for minimizing environmental impacts, yet rely heavily on a sound understanding of how ecosystems will respond to environmental stressors, and the thresholds that delineate benign and harmful conditions. Here, we use novel statistical approaches and mathematical tools to account for uncertainty in deriving in situ dose–response relationships and thresholds for the environmental management of dredging, based on estimates of the probability of non‐zero mortality of corals during a dredging campaign at Barrow Island, Western Australia. Using modified receiver operating characteristic curves, we derive thresholds with explicit Type I and Type II errors rates, across the full range of primary stress pathways and exposure dimensions (intensity, frequency and duration). Monitoring coral health and mortality can be expensive and water quality indicators are often used to supplement direct receptor monitoring during dredging management. We found strong relationships between coral mortality and a range of water quality exposure metrics, lending support to the use of water quality metrics as management tools for protecting corals during dredging. Metrics based on sediment deposition were more statistically powerful than those based on either light or turbidity, but may be more difficult to implement in practice. Thresholds reflecting aversion to a false sense of security in environmental protection or aversion to the costs of false alarms varied substantially for all exposure metrics examined. Synthesis and applications. Strategies for managing environmental harm under uncertainty are critical to achieving an informed risk‐weighted balance between environmental protection outcomes and development costs. Our study demonstrates the complexities of how communities respond to variable environmental exposure across a range of pressures in time and space, and the value of integrating probabilistic approaches in environmental management to account for that complexity and its associated uncertainty. Coral mortality was strongly related to a range of water quality exposure metrics associated with dredging activities, and regulatory thresholds based on water quality can provide a solid and cost‐effective foundation for protecting corals during dredging. The probabilistic dose–response relationships and thresholds presented here are the first to be derived from in situ data using dredging related coral mortality and represent a step forward in integrating formal decision science approaches into environmental management.

Many eyes on the ground: citizen science is an effective early detection tool for biosecurity

Early detection of target non-indigenous species is one of the most important determinants of a successful eradication campaign. For early detection to be successful, and provide the highest probability of achieving eradication, intense surveillance is often required that can involve significant resources. Volunteer based monitoring or “citizen science” is one potential tool to address this problem. This study differs from standard citizen science projects because the participants are personnel or contractors of a company working on Barrow Island, Western Australia. We show that personnel can contribute successfully to a surveillance program aimed at detecting a broad taxonomic range of non-indigenous vertebrate and invertebrate species. Using data collected over a five year surveillance period on Barrow Island, we show that eighteen of the nineteen (95%) non-indigenous invertebrate species new to the island were detected by personnel working on the island, and that the number of detections made by these workers was significantly related to the number of personnel on the island at any one time. Most personnel detections (91%) were made inside buildings where the majority of active surveillance tools could not be implemented. For vertebrates, 4 NIS species detections (100% of detections) were made in the built environment by personnel. Although reporting of suspect non-indigenous species is voluntary, personnel are required to attend inductions and toolboxes where reporting of suspect biosecurity risk material is encouraged. These results demonstrate the value of industry led ‘citizen science’ programs, resulting in sustained stewardship and conservation of areas with high environmental value.

Detection and phylogenetic characterisation of novel Anaplasma and Ehrlichia species in Amblyomma triguttatum subsp. from four allopatric populations in Australia

Anaplasma and Ehrlichia spp. are tick-borne pathogens that can cause severe disease in domestic animals, and several species are responsible for emerging zoonoses in the northern hemisphere. Until recently, the only members of these genera reported in Australia (A. marginale, A. centrale, and A. platys) were introduced from other continents, through the importation of domestic animals and their associated ticks. However, unique Anaplasma and Ehrlichia 16S rRNA gene sequences were recently detected for the first time in native Australian ticks, particularly in Amblyomma triguttatum subsp. ticks from southwest Western Australia (WA). We used molecular techniques to survey Am. triguttatum subsp. ticks from four allopatric populations in southern and western Australia for Anaplasma and Ehrlichia species, and described here the phylogeny of these novel organisms. An A. bovis variant (genotype Y11) was detected in ticks from two study sites; Yanchep National Park (12/280, 4.3%) and Barrow Island (1/69, 1.4%). Phylogenetic analysis of 16S rRNA and groEL gene sequences concluded that A. bovis genotype Y11 is a unique genetic variant, distinct from other A. bovis isolates worldwide. Additionally, a novel Ehrlichia species was detected in Am. triguttatum subsp. from three of the four study sites; Yanchep National Park (18/280, 6.4%), Bungendore Park (8/46, 17.4%), and Innes National Park (9/214, 4.2%), but not from Barrow Island. Phylogenetic analysis of 16S, groEL, gltA, and map1 gene sequences revealed that this Ehrlichia sp. is most closely related to, but clearly distinct from, E. ruminantium and Ehrlichia sp. Panola Mountain. We propose to designate this new species ‘Candidatus Ehrlichia occidentalis’. Anaplasma bovis genotype Y11 and ‘Candidatus E. occidentalis’ are the first Anaplasma and Ehrlichia species to be recorded in native Australian ticks.

Early human occupation of a maritime desert, Barrow Island, North-West Australia

Archaeological deposits from Boodie Cave on Barrow Island, northwest Australia, reveal some of the oldest evidence for Aboriginal occupation of Australia, as well as illustrating the early use of marine resources by modern peoples outside of Africa. Barrow Island is a large (202 km2) limestone continental island located on the North-West Shelf of Australia, optimally located to sample past use of both the Pleistocene coastline and extensive arid coastal plains. An interdisciplinary team forming the Barrow Island Archaeology Project (BIAP) has addressed questions focusing on the antiquity of occupation of coastal deserts by hunter-gatherers; the use and distribution of marine resources from the coast to the interior; and the productivity of the marine zone with changing sea levels. Boodie Cave is the largest of 20 stratified deposits identified on Barrow Island with 20 m3 of cultural deposits excavated between 2013 and 2015. In this first major synthesis we focus on the dating and sedimentology of Boodie Cave to establish the framework for ongoing analysis of cultural materials. We present new data on these cultural assemblages – including charcoal, faunal remains and lithics – integrated with micromorphology, sedimentary history and dating by four independent laboratories. First occupation occurs between 51.1 and 46.2 ka, overlapping with the earliest dates for occupation of Australia. Marine resources are incorporated into dietary assemblages by 42.5 ka and continue to be transported to the cave through all periods of occupation, despite fluctuating sea levels and dramatic extensions of the coastal plain. The changing quantities of marine fauna through time reflect the varying distance of the cave from the contemporaneous shoreline. The dietary breadth of both arid zone terrestrial fauna and marine species increases after the Last Glacial Maximum and significantly so by the mid-Holocene. The cave is abandoned by 6.8 ka when the island becomes increasingly distant from the mainland coast.

Zero-tolerance biosecurity protects high-conservation-value island nature reserve

Barrow Island, north-west coast of Australia, is one of the world’s significant conservation areas, harboring marsupials that have become extinct or threatened on mainland Australia as well as a rich diversity of plants and animals, some endemic. Access to construct a Liquefied Natural Gas (LNG) plant, Australia’s largest infrastructure development, on the island was conditional on no non-indigenous species (NIS) becoming established. We developed a comprehensive biosecurity system to protect the island’s biodiversity. From 2009 to 2015 more than 0.5 million passengers and 12.2 million tonnes of freight were transported to the island under the biosecurity system, requiring 1.5 million hrs of inspections. No establishments of NIS were detected. We made four observations that will assist development of biosecurity systems. Firstly, the frequency of detections of organisms corresponded best to a mixture log-normal distribution including the high number of zero inspections and extreme values involving rare incursions. Secondly, comprehensive knowledge of the island’s biota allowed estimation of false positive detections (62% native species). Thirdly, detections at the border did not predict incursions on the island. Fourthly, the workforce detected more than half post-border incursions (59%). Similar approaches can and should be implemented for all areas of significant conservation value.

Application of Quantitative Mineralogical Analysis in Archaeological Micromorphology: a Case Study from Barrow Is., Western Australia

This study assesses the use of the Tescan Integrated Mineral Analyser (TIMA) platform, which integrates scanning electron microscopy—energy dispersive spectroscopy (SEM-EDS) chemical analysis with mineral identification software, to quantitatively determine the mineralogical composition of sediments in archaeological research. Ten samples, spanning 50,000 years of sedimentation, were examined from archaeological excavation profiles in the Boodie Cave, Barrow Island, Western Australia. TIMA mineral abundance data show a gradual change from a polymineralogic quartz-rich assemblage from ~50–12 ka to a more simple carbonate-dominate assemblage from the terminal Pleistocene. This trend is consistent with a decreasing contribution of reworked terrestrial siliciclastic sediments derived from the mainland and an increase in carbonate sediments of marine derivation, as the exposed coastal plain become submerged during post-glacial sea-level rise. SEM-EDS analysis has also provided empirical data on cultural materials, mainly bone and shell fragments that similarly reflect the increasing contribution of marine fauna into the Holocene sediments. Particularly useful is the ability of mineral mapping function of the TIMA outputs to help distinguish 16 sub-units representing sections of the main nine stratigraphic units, including at least three contiguous midden events. The SEM-EDS data indicate that the redeposited sediments were derived from the overlying midden unit, with layering reflecting differential settling of mineral phases. This study demonstrates that automated mineralogy studies using TIMA can clearly aid the identification of provenance and processes within archaeological sediments and soils.

Unearthing Barrow Island’s Past: The Historical Archaeology of Colonial-Era Exploitation, Northwest Australia

The “modern world” of recent centuries is characterized by colonialism and imperialism, greater instances of cultural encounter and competition, increasing global connectivity, and the enhanced movement of resources and people especially for their labor (Falk 1991; Orser 1996). Northwest Australia provides important insight into these elements of modernity, as a region where the capitalist production of resources for international markets followed British colonization and relied on forms of non-European labor, both Indigenous Australian and Asian. This paper describes Barrow Island in the Northwest Australian maritime desert where archaeological research at recently discovered historic settlements indicates the deliberate translocation of Aboriginal people to the island presumably by white pearlers. The sites provide new information regarding commercial extractive industries, particularly the colonial pearl fisheries and their multicultural and exploitative nature.

The burrowing bettongs of Barrow Island: demographic and genetic insights into a threatened macropod

Islands provide the last refuge for many Australian species that have succumbed to range contractions since European settlement. These species have heightened vulnerability when developments are planned for the islands. The burrowing bettong (Bettongia lesueur), a threatened macropod, was once widespread across Australia but now occurs naturally only on Barrow Island and two other Western Australian offshore islands. Here, we document the demographic, social and genetic characteristics of the Barrow Island population, using nuclear microsatellites, mtDNA and demographic parameters from 286 individuals trapped around 29 warrens. The Barrow Island population utilises complex warren systems scattered across the landscape and exhibits continuous breeding, even during extensive dry conditions. Males (759 g) were significantly heavier than females (735 g), with the latter reaching sexual maturity at ~600 g. Warrens varied markedly in size and number of individuals, with 20% of females and 25% of males moving between nearby warrens. There were two deep mtDNA haplotype clades that coalesce around 298 000 years ago, indicating that this island population has maintained an effective population size that has permitted the retention of one marked feature of its preisolation genetic diversity. Dispersal and gene flow between warrens was severely constrained. Both mtDNA and 11 nuclear microsatellites showed a strong isolation by distance effect, with genetic differences between warrens increasing linearly with geographic separation. While this was marked in both sexes, it was stronger in females and consistent with shorter dispersal distances for females than for males. The trapping and genetic data are concordant, with between-warren sociality correlated with genetic similarity. Long-term conservation, management and translocation programs will benefit from cognisance of the strong fidelity to natal areas, as evidenced by both recapture data and genetic analyses.

Allegory of a cave crustacean: systematic and biogeographic reality of Halosbaena (Peracarida: Thermosbaenacea) sought with molecular data at multiple scales

Halosbaena Stock, 1976 are small crustaceans found in a number of distant, isolated subterranean locations in the Northern (Caribbean and Canary Islands) and Southern Hemispheres (Christmas Island and north-western Australia in Cape Range, Barrow Island and Pilbara regions). This distribution is surprising for an animal that produces few eggs, has no free-living larval stage, and succours their young in a dorsal brood pouch. It is usually explained by the passive movement of ancestral populations on tectonic plates as the ancient Tethys Ocean spread. We used molecular data (one mitochondrial and three nuclear genes) to reconstruct phylogenies and time-trees to understand their biogeography at the global scale and at four diminishing scales within the Southern Hemisphere. We found: (1) a basal split between species in the Northern and Southern Hemispheres, but the inferred ages of divergences between species are not old enough to be associated with the spread of the Tethys; (2) a recently discovered species from Christmas Island which is the sister to Australian mainland taxa; (3) the one described species from mainland Australia, H. tulki, probably constitutes at least five separate species that reflect local geography (Cape Range west, Cape Range east, Barrow Island, Pilbara low elevation, Pilbara high elevation); (4) the Pilbara high elevation taxon is likely not old enough to have been stranded high inland during an Eocene marine transgression; and (5) phylogeographic breaks within Cape Range west are congruent with other breaks in sympatric cave species.

A revision of the genusOrosiusDistant (Hemiptera: Cicadellidae) based on male genitalia and DNA barcoding

AbstractA morphological and molecular review of the genusOrosiusDistant (Deltocephalinae: Opsiini) was undertaken using male genitalia and DNA barcoding. We recognise 14 valid species of the genus, of which two were indeterminate, based on females only and recognised only by DNA barcodes.Orosius argentatus(Evans) stat. rev. is removed from synonymy withOrosius orientalis(Matsumura) after DNA barcoding demonstrated that the two species are distinct; small but consistent differences in the male genitalia are also found to support the two species hypothesis. The other species, recognised on male genitalia, are confirmed with DNA barcode sequence data. These species areOrosius albicinctusDistant,Orosius lotophagorum(Kirkaldy),Orosius canberrensis(Evans),Orosius ryukyuensis(Ishihara) andOrosius cellulosus(Lindberg), plus five new species described herein asOrosius albifronsFletcher & Löcker sp. nov. andOrosius brunneusFletcher & Löcker sp. nov. from Barrow Island, Western Australia,Orosius recurvusFletcher & Löcker sp. nov. from New South Wales andOrosius magareyiFletcher & Löcker sp. nov. andOrosius pallidusFletcher & Löcker sp. nov. from Loxton, South Australia. This is the first record ofO. cellulosusfrom Australia.Orosius aegypticusGhauri syn. nov. is synonymised withO. albicinctus, the synonymy ofNesaloha cantonisOman syn. nov. is transferred toO. orientalisfromO. argentatusandOrosius argentatus novaebrittaniaeGhauri syn. nov. is synonymised withO. orientalis. Orosius minuicusDlabola is excluded from the genus. A key for the discrimination and identification of the species based on male genitalia is provided.