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The evolution of the ‘therevoid’ clade, with an emphasis on window flies (Scenopinidae), is presented by combining DNA sequence data with morphological characters for living and fossil species. The therevoid clade represents a group of four families (Apsilocephalidae, Evocoidae, Scenopinidae and Therevidae) of lower brachyceran Diptera in the superfamily Asiloidea. A comprehensive phylogenetic analysis using parsimony and likelihood methods was undertaken using extensive taxon sampling from all families and subfamilies, and compared with outgroup taxa sampled from the related families Asilidae, Mydidae, Apioceridae and Empididae. Fifty‐nine morphological characters (adult, larval and pupal) were combined with 6.4 kb of DNA sequences for two ribosomal genes (16S and 18S ribosomal DNA) and three protein‐encoding genes [cytochrome oxidase I (COI), triose phosphate isomerase (TPI) and the CPSase region of carbamoyl‐phosphate synthase‐aspartate transcarbamoylase‐dihydroorotase (CAD)]. Results from combined analyses of morphological and molecular data for 78 taxa representing all families of the therevoid clade are presented. Specific hypotheses of the relationship between respective families and subfamilies were tested statistically using four‐cluster likelihood mapping. The therevoid clade is a well‐supported monophyletic group within Asiloidea, with Evocoidae sister to Apsilocephalidae and Therevidae sister to Scenopinidae. Temporal and zoogeographical aspects of therevoid clade evolution were investigated using Bayesian divergence time estimates and Lagrange ancestral range scenarios. The effect of inclusion of fossils as terminal taxa on phylogenetic and divergence time estimation was investigated, with morphological scoring for fossil representatives included in the analyses rather than used simply as minimum age constraints. In each analysis there was either improvement in estimation, or only marginal and localized loss in tree resolution, and with younger estimates of divergence time across the tree. The historical biogeography of the therevoid clade was examined with multiple trans‐Antarctic vicariance events between Australasia and South America evident during the Late Cretaceous to early Palaeogene. Scenopininae is newly subdivided into two tribes, Metatrichini trib.n. and Scenopinini Fallén stat.r. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:4974EBF8‐3117‐4189‐B6DE‐7D5BF9B23E53 . 相似文献
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The imposition of the stresses of climate change (higher temperatures and in many regions lower rainfall) on existing stressors, such as habitat loss and degradation, will increase pressures on native fauna already experiencing declines. We focused on assessing how the ‘Big Dry’ (severe drought, 1997–2010) in south‐eastern Australia affected populations of a small marsupial carnivore, the yellow‐footed antechinus (Antechinus flavipes), in box‐ironbark forests, which suffer a range of anthropogenic disturbances. Trapping of the mammal was conducted on 136 (0.25 ha) sites in two box‐ironbark forests in 2004, 2005 and 2011 (46 or 64 sites per year). Capture rates of all distinct individuals, males and second‐year females with suckled teats, and the number of suckled teats were positively associated with rainfall in the previous September (time of lactation and deposition of young in nests). Despite differences between forests in capture rates of all individuals, the positive effect of rainfall was evident in both forests. Populations in one forest, Chiltern, were substantially larger than other locations surveyed in 2004 and 2005, yet crashed to small numbers in 2011. This crash was most likely due to low rainfall in the preceding years including the lowest recorded annual rainfall (2006), below‐average annual rainfall (2007, 2008 and 2009) and well‐below‐average rainfall in September (2006, 2007 and 2008). The predicted drying and warming climate in south‐eastern Australia and habitat loss and degradation pose a threat to the viability of the yellow‐footed antechinus in box‐ironbark forests. An integrated approach to small‐mammal management is necessary given that the region may be facing additional losses, especially during droughts, to those already experienced since the early 1800s. Our work emphasizes the need to identify specific effects of stressors on vital demographic characteristics of species. 相似文献
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PETER H. KERR SHAUN L. WINTERTON 《Biological journal of the Linnean Society. Linnean Society of London》2008,93(1):9-13
We provide the first evidence of a small-headed fly planidium (first instar larva; Diptera: Acroceridae) associated with a whirligig mite (Acari: Acariformes: Prostigmata: Anystina: Anystidae) in Baltic amber. This fossil is surprising as parasitic nematodes are the only metazoans known to successfully attack acariform mites, and Acroceridae are believed to be host-restricted parasitoids of spiders. The fossil corroborates a previously published, but widely dismissed, paper that first reported parasitism of parasitengone mites by acrocerid planidia. The possible natural history implications of this find are discussed. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 9–13. 相似文献
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SHAUN A. FORGIE SARA L. GOODACRE MARTIN I. TAYLOR BRENT C. EMERSON 《Molecular ecology resources》2006,6(3):820-822
The Canary Island pine weevil Brachyderes rugatus (Wollaston) consists of four allopatric subspecies that are thought to have arisen from several historic colonization events within the archipelago. We have isolated and optimized seven microsatellite loci from Brachyderes rugatus calvus from Gran Canaria. Six of these loci are polymorphic within B. rugatus (11–22 alleles per locus; heterozygosity between 0.43 and 0.84). There is no evidence for heterozygote deficit within populations or for linkage disequilibrium between pairs of loci. These molecular markers are likely to prove useful tools for quantifying the genetic variability of bottlenecked island populations. 相似文献
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SHAUN L. WINTERTON NATE B. HARDY STEPHEN D. GAIMARI MARTIN HAUSER HILARY N. HILL KEVIN C. HOLSTON MICHAEL E. IRWIN CHRISTINE L. LAMBKIN MARK A. METZ FEDERICA TURCO LONGLONG YANG DAVID K. YEATES BRIAN M. WIEGMANN 《Systematic Entomology》2016,41(1):144-161
The therevoid clade represents a group of four families (Apsilocephalidae, Evocoidae, Scenopinidae and Therevidae) of lower brachyceran Diptera in the superfamily Asiloidea. The largest of these families is that of the stiletto flies (Therevidae). A large‐scale (i.e. supermatrix) phylogeny of Therevidae is presented based on DNA sequence data from seven genetic loci (16S, 18S and 28S ribosomal DNA and four protein‐encoding genes: elongation factor 1‐alpha, triose phosphate isomerase, short‐wavelength rhodopsin and the CPSase region of carbamoyl‐phosphate synthase‐aspartate transcarbamoylase‐dihydroorotase). Results are presented from Bayesian phylogenetic analyses of approximately 8.7 kb of sequence data for 204 taxa representing all subfamilies and genus groups of Therevidae. Our results strongly support the sister‐group relationship between Therevidae and Scenopinidae, with Apsilocephalidae as sister to Evocoidae. Previous estimates of stiletto fly phylogeny based on morphology or DNA sequence data, or supertree analysis, have failed to find significant support for relationships among subfamilies. We report for the first time strong support for the placement of the subfamily Phycinae as sister to the remaining Therevidae, originating during the Mid Cretaceous. As in previous studies, the sister‐group relationship between the species‐rich subfamilies Agapophytinae and Therevinae is strongly supported. Agapophytinae are recovered as monophyletic, inclusive of the Taenogera group. Therevinae comprise the bulk of the species richness in the family and appear to be a relatively recent and rapid radiation originating in the southern hemisphere (Australia + Antarctica + South America) during the Late Cretaceous. Genus groups are defined for all subfamilies based on these results. 相似文献
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SHAUN C. CUNNINGHAM J. R. THOMSON J. READ P. J. BAKER R. MAC NALLY 《Austral ecology》2010,35(3):348-356
Forest dieback is a worldwide problem that is likely to increase with climate change and increasing human demands for resources. Eucalyptus camaldulensis forests are an acute example of forest dieback, with 70% of the Victorian Murray River floodplain in some state of dieback. If we are to halt dieback in these floodplain forests, we need to understand what makes stands susceptible to dieback. Forest diebacks are often related to stand structure, with dieback more severe in senescent or high‐density stands. We determined whether certain stand structures make these forests more susceptible to dieback. We undertook an extensive survey of 176 stands across 100 000 ha of forest, covering the range of stand condition on this floodplain. Large and small trees (20‐, 40‐, 80‐ and 120‐cm diameter) showed a similar reduction in the probability of being alive with decreasing stand condition. A slight improvement in stand condition was found at higher densities and basal areas, which may reflect the higher productivity or younger age of these stands. Stand condition was moderately, positively correlated with longitude, with stand condition being higher in the east of the Murray River floodplain where flooding frequencies are currently higher. This suggests that dieback of these floodplain forests would be more effectively mitigated by increased water availability through flooding than by altering stand structure. 相似文献
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GREGORY F. B. HORROCKS SHAUN C. CUNNINGHAM DENNIS J. O'DOWD JAMES R. THOMSON RALPH MAC NALLY 《Austral ecology》2012,37(4):518-528
Understanding how species respond to differences in resource availability is critical to managing biodiversity under the increasing pressures associated with climate change and growing human populations. Over the last century, the floodplain forests of Australia's largest river system, the Murray‐Darling Basin, have been much affected by intensive harvesting of timber and firewood, and increasingly stressed by river regulation and, recently, an extended drought. Fallen timber – logs and shed branches – is known to play a key role in the ecology of several important species on these floodplains. Here, we monitored the response of the ant assemblages of a floodplain forest along the Murray River to a large‐scale (34 ha) experimental manipulation of fallen‐timber load (0 to 80 t ha?1) over 4 years. The forest was subjected to an incidental, extensive flood that enabled us to examine how two important stressors (timber removal and river regulation) affect ant assemblages. Ants showed little response to the proximity of fallen timber within plots, prior to the flood, or to different loads among plots, unlike other floodplain biota. After the flood, both ant abundance and species richness increased and species composition changed. However, this increase in species richness after flooding was less pronounced in plots with higher amounts of fallen timber. Managing river red gum forest using a mosaic of flood regimes, more representative of historical conditions, is likely to be the most effective way to maintain and enhance the diversity of ants and other biota on these important floodplains. 相似文献
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