Interspecies sexual conflict : evidence of interspecies sexual mimicry in a sympatric pair of traumatically inseminating insects

Sexual conflict is widely accepted as a significant evolutionary driver, which can fuel coevolutionary arms races between the sexes and may even lead to speciation. In the traumatically inseminating plant bug genus Coridromius, mating is aggressive and fast, with males pouncing on unsuspecting females, and females thrashing, kicking and jumping in an effort to dislodge their would-be suitors. Here I report the discovery of two sister species of Coridromius living sympatrically on the same host plants in Tahiti, and present evidence of interspecies sexual mimicry, thought to be driven by reproductive interference.1 page(s

Molecular Phylogeny Of The Kosciuscola Grasshoppers Endemic To The Australian Alpine And Montane Regions

Diversity and speciation in Australia\u27s alpine biota are poorly understood. Here we present a molecular phylogeny of the Australian alpine grasshopper genus Kosciuscola (Sjösted) that currently includes five described species. These grasshoppers are of interest not only because of their alpine distribution but also for the extraordinary colour change exhibited by the species K. tristis, whose males turn turquoise when their body temperature exceeds 25°C. We reconstructed the phylogeny with two fragments of the mitochondrial genome using parsimony, maximum likelihood and Bayesian analyses and our data support the current taxonomy. Further, our data show little geographic structuring within some clades, which is puzzling since members of Kosciuscola are brachypterous. Finally, our data coupled with our observations on colouration provide evidence for a genetically distinct clade of K. tristis in the Victorian Alps. This is among the first molecular studies of an alpine invertebrate and one of a few on non-endangered, widespread Australian alpine species. More phylogenetic studies in the Australian Alps are required if we are to understand the evolution of alpine fauna and establish baseline data to monitor their response to climate change. © 2013 CSIRO

Molecular phylogeny of the Kosciuscola grasshoppers endemic to the Australian alpine and montane regions

Diversity and speciation in Australia's alpine biota are poorly understood. Here we present a molecular phylogeny of the Australian alpine grasshopper genus Kosciuscola (Sjösted) that currently includes five described species. These grasshoppers are of interest not only because of their alpine distribution but also for the extraordinary colour change exhibited by the species K. tristis, whose males turn turquoise when their body temperature exceeds 25°C. We reconstructed the phylogeny with two fragments of the mitochondrial genome using parsimony, maximum likelihood and Bayesian analyses and our data support the current taxonomy. Further, our data show little geographic structuring within some clades, which is puzzling since members of Kosciuscola are brachypterous. Finally, our data coupled with our observations on colouration provide evidence for a genetically distinct clade of K. tristis in the Victorian Alps. This is among the first molecular studies of an alpine invertebrate and one of a few on non-endangered, widespread Australian alpine species. More phylogenetic studies in the Australian Alps are required if we are to understand the evolution of alpine fauna and establish baseline data to monitor their response to climate change.10 page(s

Anacoracid sharks and calcareous nannofossil stratigraphy of the mid-Cretaceous ‘upper’ Gearle Siltstone and Haycock Marl in the lower Murchison River area, Western Australia

Extensive bulk sampling over the past 20 years and greatly improved stratigraphic control permitted a meaningful revision of previously described anacoracid sharks from the ‘upper’ Gearle Siltstone and lower Haycock Marl in the lower Murchison River area, Western Australia. Isolated teeth of anacoracids are rare in the lower three (Beds 1–3) of four stratigraphic units of the ‘upper’ Gearle Siltstone but relatively common in the uppermost layer (Bed 4) and in the lower part of the overlying Haycock Marl. On the basis of calcareous nannofossils, Beds 1 and 2 of the ‘upper’ Gearle Siltstone can be placed in the uppermost upper Albian calcareous nannofossil Subzone CC9b whereas Bed 3 can be referred to the lowermost Cenomanian CC9c Subzone. Bed 1 yielded fragments of strongly serrated anacoracid teeth as well as a single, smooth-edged tooth. The samples from Beds 2 and 3 contained a few small fragments of serrated anacoracid teeth. Bed 4 is barren of calcareous nannofossils but the presence of a dentally advanced tooth of the cosmopolitan lamniform genus Cretoxyrhina in combination with the age of the overlying Haycock Marl indicate deposition within the younger half of the Cenomanian. The unit produced teeth of two anacoracids; Squalicorax acutus sp. nov. and S. bazzii sp. nov. The basal, laminated part of the Haycock Marl is placed in the uppermost upper Cenomanian part of CC10b. It yielded Squalicorax mutabilis sp. nov. and S. aff. S. bernardezi. Exceptionally well-preserved teeth of the former species span a 5:1 size ratio range for teeth of comparable jaw position. The teeth reveal strong ontogenetic heterodonty with a large increase in the relative size of the main cusp with age and the transition from a vertical distal heel of the crown in very young juveniles to a sub-horizontal, well demarcated heel in ‘adult’ teeth. An isolated phosphatic lens in the lower part of the Haycock Marl produced calcareous nannofossils indicative of the CC10b SubZone, most likely the lowermost lower Turonian part. It contains teeth of Squalicorax mutabilis sp. nov., S. aff. S. bernardezi, and S. sp. C