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We: (i) report the rediscovery of Ixodes (Sternalixodes) confusus Roberts, 1960 in Australia; (ii) redescribe the male and female of I. confusus ; (iii) describe the mitochondrial (mt) genome of I. confusus from five ticks from four localities in Far North Queensland; and (iv) present the first substantial phylogeny of the subgenera of the Ixodes. The mt genomes of I. confusus, I. cornuatus, I. hirsti, I. myrmecobii and I. trichosuri are presented here for the first time. In our phylogeny from entire mt genomes (ca. 15 kb), the subgenus Endopalpiger was the sister-group to subgenera Sternalixodes plus Ceratixodes plus Exopalpiger whereas Exopalpiger was the sister to Sternalixodes plus Ceratixodes. [i.e. ((Endopalpiger) (Sternalixodes, Ceratixodes and Exopalpiger))]. Finally, we show that Ixodes anatis , the kiwi tick, may be closely related to the ticks of marsupials of Australia and Papua New Guinea. [Display omitted] • Rediscovery in Australia of the tick, Ixodes confusus. • First description of the male of Ixodes confusus from Australia. • Nine new mitochondrial genomes of Ixodes ticks from Australia and first substantial phylogeny of the subgenera of Ixodes. • Ixodes anatis , a tick of the kiwi bird of NZ may be a closely related to the ticks of marsupials of Australia and PNG. [ABSTRACT FROM AUTHOR]

The ecological effects of clearfell harvesting followed by high intensity burning are sometimes thought to mimic wildfire, the major natural disturbance regime in Tasmanian wet forests. We investigated whether the litter-inhabiting beetle populations in logged and burnt regeneration forest resembled those in forest regenerating following natural wildfire. Pitfall trapping and habitat assessment were conducted at three pairs of adjacent 33-year-old logging and wildfire regeneration sites. In total, 6128 beetles were collected, representing 179 morphospecies in 30 families. The beetle assemblages in logging and wildfire treatments could not be distinguished. However, beetle populations did differ subtly between sites. One Aleocharinae (Staphylinidae) morphospecies and one Carabidae species were more abundant at one of the three site pairs. Multivariate analyses of common species indicated that the litter beetle assemblages differed significantly between sites, and this was partially related to their degree of geographical separation. Environmental factors considered indicative of logging impacts did not differ between wildfire and logging regeneration treatments.Temporal and landscape scale differences between logging and the natural disturbance regime and changes to logging practices since these study sites were harvested may have negative impacts on litter beetles in the future. Changes to current harvesting practices are recommended to better mimic the natural disturbance regime and thus improve conservation of forest biodiversity. [Copyright &y& Elsevier]

The setae of mites are not regarded as secretory structures, yet in the flat mite genus Raoiella , each developmental stage presents droplets of fluid associated with the tips of their dorsal setae. To understand the origin of this fluid, the ultrastructure of the dorsal setae is investigated in females of Raoiella bauchani Beard & Ochoa and the invasive pest species Raoiella indica Hirst using scanning and transmission electron microscopy techniques. The dorsal setae are barbed along their entire length and have either a broadened plumose or a flat spatulate tip. Ultrastructurally, they present the typical features of mechanoreceptors, but have a "hollow" axis represented by a protoplasmatic core containing dendritic branches. This combination of ultrastructural characters indicates that the setae might be multimodal receptors: acting as both mechanoreceptors and contact chemoreceptors. The epidermal cells that underlie the setal sockets are columnar and have an ultrastructure that suggests they have a glandular function. Moreover, these cells present regular microvilli apically and form extracellular cuticular canals, containing epicuticular filaments, that are connected with the microvilli proximally and which open via pores onto the surface of the setal base distally. This arrangement indicates that the secretion from the microvilli passes into the canals and is then conducted to pores at the base of the seta, where it then accumulates and moves up the setal shaft, along the longitudinal grooves of the barbs. Based on similar arrangements in some insect taxa, the organization of the structures here observed in Raoiella suggests the passage of a non-polar, water insoluble, lipoid fluid through the cuticle, the function of which is still obscure. • Dorsal setae in the genus Raoiella could act as both mechanoreceptor and contact chemoreceptors. • Structure of epidermal cells underlying the dorsal setae suggests an active secretory role. • These secretory cells are connected to extracellular tubule cuticular structures. • Tubule structures open via pores on the side walls of the setal sockets. • Presence of epicuticular filaments suggests an involvement in the transport mechanisms of waterproofing lipoid materials. [ABSTRACT FROM AUTHOR]