Taxonomy, development and morphology of the immature stages of Cicadellidae (Homptera)

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A revised key to the living and fossil families of Strepsiptera, with the description of a new family, Cretostylopidae

A new family, Cretostylopidae Kathirithamby and Engel, is erected to accommodate the mid-Cretaceous species Cretostylops engeli Grimaldi and Kathirithamby. Based on this as well as various other recent works pertaining to the higher classification of Strepsiptera, a revised key is provide to the living and fossil families

First host record and description of female Halictophagus calcaratus Pasteels (Strepsiptera: Insecta) from South Africa

The strepsipteran, Halictophagus calcaratus, was described from South Africa by Pasteels in 1958, but no host record/s or females were included. Here we record that H. calcaratus parasitizes the cicadellid, Molopopterus theae Theron 1978, an important pest of the commercially produced shrub, Aspalathus linearis (Fabaceae), from which ‘Rooibos’ tea is produced. We provide a redescription of the male and a description of the female and the male cephalotheca. A checklist of South African Strepsiptera is included

Social wasps desert the colony and aggregate outside if parasitized: parasite manipulation?

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Transcriptomics of an extended phenotype: Parasite manipulation of wasp social behaviour shifts expression of caste-related genes

Parasites can manipulate host behaviour to increase their own transmission and fitness, but the genomic mechanisms by which parasites manipulate hosts are not well understood. We investigated the relationship between the social paper wasp, Polistes dominula, and its parasite, Xenos vesparum (Insecta: Strepsiptera) to understand the effects of an obligate endoparasitoid on its host’s brain transcriptome. Previous research suggests that X. vesparum shifts aspects of host social caste-related behaviour and physiology in ways that benefit the parasitoid. We hypothesized that X. vesparum-infested (stylopized) females would show a shift in caste-related brain gene expression. Specifically, we predicted stylopized females, who would normally be workers, would show gene expression patterns resembling pre-overwintering queens (gynes), reflecting gyne-like changes in behaviour. We used RNA-sequencing data to characterize patterns of brain gene expression in stylopized females, and compared these to those of unstylopized workers and gynes. In support of our hypothesis, we found that stylopized females, despite sharing numerous physiological and life history characteristics with members of the worker caste, show gyne-shifted brain expression patterns. These data suggest the parasitoid affects its host by exploiting phenotypic plasticity related to social caste, thus shifting naturally occurring social behaviour in a way that is beneficial to the parasitoid

Differential expression of the adult specifier E93 in the strepsipteran Xenos vesparum Rossi suggests a role in female neoteny

Holometaboly is a key evolutionary innovation that has facilitated the spectacular radiation of insects. Despite the undeniable advantage of complete metamorphosis, the female of some holometabolous species have lost the typical holometabolous development through neoteny. In Xenos vesparum Rossi (Strepsiptera: Stylopidae), a derived species of the holometabolous endoparasitic order Strepsiptera, neotenic females reach sexual maturity without the pupal and the imaginal stages, thus retaining their larval morphology (with the exception of the anterior part of the body or cephalothorax), while males undergo normal pupal-based metamorphosis. Expression of the “adult-specifier” E93 factor has been shown to be required for proper metamorphosis in holometabolous insects. Here, we investigated the involvement of E93 in female neoteny by cloning XvE93. Interestingly, while we detected a clear up-regulation of XvE93 expression in pupal and adult stages of males, persistent low levels of XvE93 were detected in X. vesparum females. However, a specific up-regulation of XvE93 was observed in the cephalothorax of late 4th female instar larva, which correlates with the occurrence of neotenic-specific features in the anterior part of the female body. Moreover, the same expression dynamic in the cephalothorax and abdomen was also observed for other two critical metamorphic regulators, the anti-metamorphic XvKr-h1 and the pupal specifier XvBr-C. The specific up-regulation of XvE93 and XvBr-C in the female cephalothorax seems to be the result of an increase in 20-hydroxyecdysone (20E) signaling in this region for we detected higher expression levels of the 20E-dependent nuclear receptors XvHR3 and XvE75 in the cephalothorax. Overall, our results detect a sex-specific expression pattern of critical metamorphic genes in X. vesparum, suggesting that neoteny in Strepsiptera results from the modification of the normal expression of E93, Br-C and Kr-h1 genes

9-Genes Reinforce the Phylogeny of Holometabola and Yield Alternate Views on the Phylogenetic Placement of Strepsiptera

Background: The extraordinary morphology, reproductive and developmental biology, and behavioral ecology of twisted wing parasites (order Strepsiptera) have puzzled biologists for centuries. Even today, the phylogenetic position of these enigmatic “insects from outer space” [1] remains uncertain and contentious. Recent authors have argued for the placement of Strepsiptera within or as a close relative of beetles (order Coleoptera), as sister group of flies (order Diptera), or even outside of Holometabola.Methodology/Principal Findings Here, we combine data from several recent studies with new data (for a total of 9 nuclear genes and ∼13 kb of aligned data for 34 taxa), to help clarify the phylogenetic placement of Strepsiptera. Our results unequivocally support the monophyly of Neuropteroidea ( = Neuropterida + Coleoptera) + Strepsiptera, but recover Strepsiptera either derived from within polyphagan beetles (order Coleoptera), or in a position sister to Neuropterida. All other supra-ordinal- and ordinal-level relationships recovered with strong nodal support were consistent with most other recent studies. Conclusions/Significance: These results, coupled with the recent proposed placement of Strepsiptera sister to Coleoptera, suggest that while the phylogenetic neighborhood of Strepsiptera has been identified, unequivocal placement to a specific branch within Neuropteroidea will require additional study.Organismic and Evolutionary Biolog