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

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The mitochondrial genome of the 'twisted-wing parasite' Mengenilla australiensis (Insecta, Strepsiptera): a comparative study

<p>Abstract</p> <p>Background</p> <p>Strepsiptera are an unusual group of sexually dimorphic, entomophagous parasitoids whose evolutionary origins remain elusive. The lineage leading to <it>Mengenilla australiensis </it>(Family Mengenillidae) is the sister group to all remaining extant strepsipterans. It is unique in that members of this family have retained a less derived condition, where females are free-living from pupation onwards, and are structurally much less simplified. We sequenced almost the entire mitochondrial genome of <it>M. australiensis </it>as an important comparative data point to the already available genome of its distant relative <it>Xenos vesparum </it>(Family Xenidae). This study represents the first in-depth comparative mitochondrial genomic analysis of Strepsiptera.</p> <p>Results</p> <p>The partial genome of <it>M. australiensis </it>is presented as a 13421 bp fragment, across which all 13 protein-coding genes (PCGs), 2 ribosomal RNA (rRNA) genes and 18 transfer RNA (tRNA) sequences are identified. Two tRNA translocations disrupt an otherwise ancestral insect mitochondrial genome order. A+T content is measured at 84.3%, C-content is also very skewed. Compared with <it>M. australiensis</it>, codon bias in <it>X. vesparum </it>is more balanced. Interestingly, the size of the protein coding genome is truncated in both strepsipterans, especially in <it>X. vesparum </it>which, uniquely, has 4.3% fewer amino acids than the average holometabolan complement. A revised assessment of mitochondrial rRNA secondary structure based on comparative structural considerations is presented for <it>M. australiensis </it>and <it>X. vesparum</it>.</p> <p>Conclusions</p> <p>The mitochondrial genome of <it>X. vesparum </it>has undergone a series of alterations which are probably related to an extremely derived lifestyle. Although <it>M. australiensis </it>shares some of these attributes; it has retained greater signal from the hypothetical most recent common ancestor (MRCA) of Strepsiptera, inviting the possibility that a shift in the mitochondrial selective environment might be related to the specialization accompanying the evolution of a small, morphologically simplified completely host-dependent lifestyle. These results provide useful insights into the nature of the evolutionary transitions that accompanied the emergence of Strepsiptera, but we emphasize the need for adequate sampling across the order in future investigations concerning the extraordinary developmental and evolutionary origins of this group.</p

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

Expression of the Pupal Determinant broad during Metamorphic and Neotenic Development of the Strepsipteran Xenos vesparum Rossi

Derived members of the endoparasitic order Strepsiptera have acquired an extreme form of sexual dimorphism whereby males undergo metamorphosis and exist as free-living adults while females remain larviform, reaching sexual maturity within their hosts. Expression of the transcription factor, broad (br) has been shown to be required for pupal development in insects in which both sexes progress through metamorphosis. A surge of br expression appears in the last larval instar, as the epidermis begins pupal development. Here we ask if br is also up-regulated in the last larval instar of male Xenos vesparum Rossi (Stylopidae), and whether such expression is lost in neotenic larviform females. We clone three isoforms of br from X. vesparum (Xv′br), and show that they share greatest similarity to the Z1, Z3 and Z4 isoforms of other insect species. By monitoring Xv′br expression throughout development, we detect elevated levels of total br expression and the Xv′Z1, Xv′Z3, and Xv′Z4 isoforms in the last larval instar of males, but not females. By focusing on Xv′br expression in individual samples, we show that the levels of Xv′BTB and Xv′Z3 in the last larval instar of males are bimodal, with some males expressing 3X greater levels of Xv′br than fourth instar femlaes. Taken together, these data suggest that neoteny (and endoparasitism) in females of Strepsiptera Stylopidia could be linked to the suppression of pupal determination. Our work identifies a difference in metamorphic gene expression that is associated with neoteny, and thus provides insights into the relationship between metamorphic and neotenic development. © 2014 Erezyilmaz et al

The First Molecular Phylogeny of Strepsiptera (Insecta) Reveals an Early Burst of Molecular Evolution Correlated with the Transition to Endoparasitism

A comprehensive model of evolution requires an understanding of the relationship between selection at the molecular and phenotypic level. We investigate this in Strepsiptera, an order of endoparasitic insects whose evolutionary biology is poorly studied. We present the first molecular phylogeny of Strepsiptera, and use this as a framework to investigate the association between parasitism and molecular evolution. We find evidence of a significant burst in the rate of molecular evolution in the early history of Strepsiptera. The evolution of morphological traits linked to parasitism is significantly correlated with the pattern in molecular rate. The correlated burst in genotypic-phenotypic evolution precedes the main phase of strepsipteran diversification, which is characterised by the return to a low and even molecular rate, and a period of relative morphological stability. These findings suggest that the transition to endoparasitism led to relaxation of selective constraint in the strepsipteran genome. Our results indicate that a parasitic lifestyle can affect the rate of molecular evolution, although other causal life-history traits correlated with parasitism may also play an important role

Xenos Rossi 1793

Xenos Rossi 1793: 49 Schistosiphon Pierce 1908: 80 [Xenos peckii Kirby 1813]. Acroschismus Pierce 1908: 79 [A. hubbardi Pierce 1908]. Vespaexenos Pierce 1909: 133 [V. crabronis Pierce 1909]. Belonogastrechthrus Pierce: 1911: 498 [B. zavattarii 1911]. Clypoxenos Brèthes 1923: 46 [C. americanus Brèthes 1923]. Brasixenos Kogan & Oliveira 1966: 346 [B. fluminesis Kogan & Oliveira]. Genotype: Xenos vesparum RossiusPublished as part of Kathirithamby, Jeyaraney & Hughes, David P., 2006, Description and biological notes of the first species of Xenos (Strepsiptera: Stylopidae) parasitic in Polistes carnifex F. (Hymenoptera: Vespidae) in Mexico, pp. 35-45 in Zootaxa 1104 on page 38, DOI: 10.5281/zenodo.17141

Halictophagidae Perkins 1905

Family Halictophagidae Perkins 1905: 98 The family Halictophagidae was erected by Perkins (1905). Yang (1964) subdivided the family into two subfamilies: Halictophaginae and Tridactylophaginae. Kinzelbach (1970) erected a new subfamily Coriophaginae, and Kathirithamby (1989, 1992) added two more subfamilies, Dipterophaginae and Blattodeaphaginae. In 1985, Drew and Allwood erected a new family Dipterophagidae to incorporate the species Dipterophagus daci from Australia which parasitizes fruit flies (Diptera: Tephritidae). Kathirithamby (1989) argued that due to several synapormorphies shared with the family Halictophagidae that Dipterophagidae is a subfamily within this family. However, Drew and Allwood in 1996 re­elevated Dipterophagidae to family level on the basis that the male has 6 antennal segments with flabella on the 3 rd segment and the female with a bell­shaped cephalothorax. However, male D. Daci have: 3 ­segmented tarsi which lack claws; short mandibles that do not overlap; short 2 ­segmented maxilla; peaked VIIIth abdominal sternite and a hooked aedeagus. Female D. daci have: the head extended over the thorax and a large brood canal. These male and female characters are shared autopomorphic characters of the family Halictophagidae. Therefore, D. daci belongs to the family Halictophagidae. Drew & Allwood (1985) and Allwood & Drew (1996) erection of this species to a new family is incorrect. Only one subfamily Halictophaginae, and one genus Halictophagus, has been found Canada and the USA.Published as part of Kathirithamby, Jeyaraney & Taylor, Steven J., 2005, A new species of Halictophagus (Insecta: Strepsiptera: Halictophagidae) from Texas, and a checklist of Strepsiptera from the United States and Canada, pp. 1-18 in Zootaxa 1056 on page 2, DOI: 10.5281/zenodo.17010

Strepsiptera

List of Strepsiptera from Mexico Family Corioxenidae Kinzelbach 1970: 106 Subfamily Triozocerinae Kinzelbach 1970: 105 Genus Triozocera Pierce 1909: 86 Genotype: Triozocera mexicana Pierce T. mexicana Pierce 1909: 86 ɗ Triozocera texana Pierce 1911: 491 Triozocera paulistan Kogan 1958: 421 Triozocera mexicana Shepard 1979: 217 Host: Pangaeus bilineatus (Say) (Hemiptera. Cydnidae) Johnson 1973; Smith & Pitts 1974 Distribituon: Veracruz, Oaxaca T. tecpanensis Brailovsky & Márquez 1974: 106 ɗ Host: unknown Distribution: Tecpan de Galeana, Guerrero T. vernalis Kifune & Brailovsky 1987: 132 ɗ Host: unknown Distribution: Juárez, Puebla Subfamily Corioxeninae Kinzelbach 1970: 106 Genus Corioxenos Blair 1936: 116 C. acucyrtophallus Cook 2001: 397 ɗ Host: unknown Distribution: Chiapas Family Halictophagidae Perkins 1905: 98 Subfamily Halictophaginae Perkins 1905: 98 Genus Halictophagus Dale (in Curtis 1832: 433) Genotype: Halictophagus curtisi Dale H. acutus Bohart 1943: 352 ɗ, &, L 1 Host: Draeculacephala mollipes (Say), D. minerva Ball (Homoptera: Cicadellidae) Johnston & Morrison 1979 Distribution: Atzcapotzalco, D. F. H. naulti Kathirithamby & Moya­Raygoza 2000: ɗ Host: Dalbulus maidis (Delong & Wolcott) (Homoptera: Cicadellidae) Distribution: Morelos, Tlatizapán Family Elenchidae Perkins 1905: 106 Genus Elenchus Curtis 1831: 385 Genotype: Stylops walkeri Curtis (= Elenchus tenuicornis (Kirby)) E. butzei Brailvosky 1981: 374 ɗ Host: unknown Distribution: Tecolutla, Veracruz E. koebelei Pierce 1908: 81 ɗ Elenchus tenuicornis Baumert 1959: 400 Elenchus heidemanni Pierce 1918: 481 Host: Liburnia sp., Prokelisia marginata (Van Duzee), Prokelisia dolus Wilson, Sogatella kolophon (Kirkaldy) (Hemiptera: Delphacidae) Distribution: Northern District E. mexicanus (Pierce 1961: 467) ɗ, &, L 1 Sogatelenchus mexicanus Pierce 1961: 740 Host: Sogatodes (Sogata) cubana (Crawford) (Homoptera: Delphacidae) Distribution: Cotaxtla, Veracruz Family Myrmecolacidae Saunders 1872: 20 Genus Caenocholax Pierce 1909: 88 Genotype: Caenocholax fenyesi Pierce 1909 C. fenyesi Pierce 1909: 88 ɗ Host: unknown Distribution: Veracruz, Tabasco C. fenyesi waloffi Kathirithamby & Johnston 2004: ɗ, & Host: Dolichoderus bispinous Olivier #m; Macroanaxipha macilenta (Saussure) #f Distribution: Veracruz, Los Tuxtlas Genus Stichotrema Hofenedera 1910: 47 Genotype: Stichotrema dallatorreanum Hofeneder S. mexicanum Kifune & Brailovsky 1987: 135 ɗ Host: unknown Distribution: Los Tuxtlas, Veracruz Stichotrema beckeri (Oliveira & Kogan 1959) Kinzelbach 1983: 33 ɗ Caenocholax beckeri Oliveira & Kogan 1959: 224 Stichotrema trilobulata Brailovsky 1974: 169 Stichotrema beckeri Luna de Carvalho 1978: 356 Stichotrema beckeri Kinzelbach 1983: 33 (fossil amber) Caenocholax wygodzinskyi Oliveira & Kogan 1959: 225 Stichotrema trilobulatum Kifune & Brailovsky 1987: 137 Stichotrema beckeri Kinzelbach & Pohl 1994: 62 (fossil amber) Host: unknown Distribution: Galeana, Guerrero Family Stylopidae Kirby 1813 Genus Melittostylopus Kinzelbach 1971: 170 ɗ Genotype: Melittostylops hesparapium Kinzelbach Genus Xenos Rossi 1793: 49 Genotype: Xenos vesparum Rossius X. hamiltoni Kathirithamby & Hughes n. sp. ɗ Host: Polistes carnifex carnifex F. (Hymenoptera: Vespidae) Distribution: Los Tuxtlas, VeracruzPublished as part of Kathirithamby, Jeyaraney & Hughes, David P., 2006, Description and biological notes of the first species of Xenos (Strepsiptera: Stylopidae) parasitic in Polistes carnifex F. (Hymenoptera: Vespidae) in Mexico, pp. 35-45 in Zootaxa 1104 on pages 41-43, DOI: 10.5281/zenodo.17141