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The cicada fauna of Western Australia is briefly reviewed. Six genera and 14 species are recorded from the State for the first time bringing the total of known species and subspecies to 105 and a list of all 105 is provided. Among the taxa here recorded are five new genera and 13 new species belonging to the tribes Macrotristriini (Illyria viridis sp. n.), Pictilini (Chrysocicada trophis sp. n.), and Cicadettini (Calipsalta gen. n., Calipsalta brunnea sp. n., C. fumosa sp. n., C. viridans sp. n., Kalarko gen. n., Kalarko ferruginosus sp. n., Ewartia adusta sp. n., Parvopsalta gen. n., Parvopsalta victoriae sp. n., Pedana gen. n., Pedana hesperia sp. n., Pegapsaltria gen. n., Pegapsaltria lutea sp. n., Pyropsalta amnica sp. n., Py. patula sp. n., and Py. rhythmica sp. n). In addition, Erempsalta hermannsburgensis (Distant, 1907) is redescribed and its presence in Western Australia (and four other States) documented for the first time. Songs are analysed for all species except two species of Pyropsalta where recordings were unavailable. 

Micro-computed tomography (µCT) is a valuable tool for visualizing microstructures and damage in fiber-reinforced composites. However, the large sets of data generated by µCT present a barrier to extracting quantitative information. Deep learning models have shown promise for overcoming this barrier by enabling automated segmentation of features of interest from the images. However, robust validation methods have not yet been used to quantify the success rate of the models and the ability to extract accurate measurements from the segmented image. In this paper, we evaluate the detection rate for segmenting fibers in low-contrast CT images using a deep learning model with three different approaches for defining the reference (ground-truth) image. The feasibility of measuring sub-pixel feature dimensions from the µCT image, in certain cases where the µCT image intensity is dependent on the feature dimensions, is assessed and calibrated using a higher-resolution image from a polished cross-section of the test specimen in the same location as the µCT image. 

Contamination of a genetic sample with DNA from one or more nontarget species is a continuing concern of molecular phylogenetic studies, both Sanger sequencing studies and next-generation sequencing studies. We developed an automated pipeline for identifying and excluding likely cross-contaminated loci based on the detection of bimodal distributions of patristic distances across gene trees. When contamination occurs between samples within a data set, a comparison between a contaminated sample and its contaminant taxon will yield bimodal distributions with one peak close to zero patristic distance. This new method does not rely on a priori knowledge of taxon relatedness nor does it determine the causes(s) of the contamination. Exclusion of putatively contaminated loci from a data set generated for the insect family Cicadidae showed that these sequences were affecting some topological patterns and branch supports, although the effects were sometimes subtle, with some contamination-influenced relationships exhibiting strong bootstrap support. Long tip branches and outlier values for one anchored phylogenomic pipeline statistic (AvgNHomologs) were correlated with the presence of contamination. While the anchored hybrid enrichment markers used here, which target hemipteroid taxa, proved effective in resolving deep and shallow level Cicadidae relationships in aggregate, individual markers contained inadequate phylogenetic signal, in part probably due to short length. The cleaned data set, consisting of 429 loci, from 90 genera representing 44 of 56 current Cicadidae tribes, supported three of the four sampled Cicadidae subfamilies in concatenated-matrix maximum likelihood (ML) and multispecies coalescent-based species tree analyses, with the fourth subfamily weakly supported in the ML trees. No well-supported patterns from previous family-level Sanger sequencing studies of Cicadidae phylogeny were contradicted. One taxon (Aragualna plenalinea) did not fall with its current subfamily in the genetic tree, and this genus and its tribe Aragualnini is reclassified to Tibicininae following morphological re-examination. Only subtle differences were observed in trees after the removal of loci for which divergent base frequencies were detected. Greater success may be achieved by increased taxon sampling and developing a probe set targeting a more recent common ancestor and longer loci. Searches for contamination are an essential step in phylogenomic analyses of all kinds and our pipeline is an effective solution. [Auchenorrhyncha; base-composition bias; Cicadidae; Cicadoidea; Hemiptera; phylogenetic conflict.]

 

Abstract Historically, most North American periodical cicada (Hemiptera: Cicadidae: Magicicada spp. Davis 1925) distribution records have been mapped at county-level resolution. In recent decades, Magicicada brood distributions and especially edges have been mapped at a higher resolution, aided by the use of GIS technology after 2000. Brood VI of the 17-yr cicadas emerged in 2000 and 2017 and is the first for which detailed mapping has been completed in consecutive generations. Overlaying the records from the two generations suggests that in some places, Brood VI expanded its range slightly between 2000 and 2017, although the measured changes are close to the lower limit of detectability given the methods used. Even so, no simple alternative to range expansion easily accounts for these observations. We also bolster Alexander and Moore’s assertion that M. cassini does not occur in Brood VI. 

A recent paper by Ruschel & Campos (2019) on “leaf-winged” cicadas proposed a significant reorganization of the cicada tribe Hemidictyini Distant, 1905g, including synonymization of the monogeneric tribe Lacetasini Moulds & Marshall, 2018 following the results of a cladistic parsimony analysis of morphological characters. In this study, we reconsider and revise the morphological analysis of Ruschel & Campos and obtain new genetic data for Hemidictya. We find that their study suffers from a limited taxon sample, inappropriate outgroup selection, and misinterpretation of genitalic characters (uncus vs. claspers). We show that Hemidictyini sensu Ruschel & Campos includes members of multiple tribes and subfamilies, and we conclude that some of the taxonomic transfers by Ruschel & Campos are not supported. The two most similar and leaf-like cicadas, Hemidictya Burmeister, 1835 (South America) and Hovana Distant, 1905g (Madagascar), are probably not closely related but rather an excellent example of convergent evolution. Lacetasini is not a junior synonym of the Hemidictyini but a distinct part of the Tettigomyiinae Distant, 1905g as originally classified. We return or transfer the genera Lacetas Karsch, 1890, Iruana Distant, 1905g, Bafutalna Boulard, 1993, and Murphyalna Boulard, 2012 to the Lacetasini. With the transfer of all genera of Iruanina Boulard, 1993 and Bafutalnina Boulard, 1993 to Lacetasini and with Lacetas transferred to the Iruanina, Lacetasini n. syn. becomes a subjective junior synonym of Iruanini rev. stat. in the Tettigomyiinae. We assign Hovana to Hovanini n. tribe in the Tettigomyiinae and Sapantanga Distant, 1905g to Sapantangini n. tribe in the Tibicininae Distant, 1905b. We propose that Hemidictyini sensu novo contains only the genus Hemidictya and we assign the tribe to Tibicininae with a revised diagnosis.