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The rapid diversification of sexual traits is a common phenomenon accompanying the evolution of reproductive isolation, yet the evolutionary mechanisms driving such diversification are often unknown. Based on experimentally evolved strains of two sister species of cactophilic Drosophila, we investigated the correlated evolution of primary and secondary sexual traits to semi-natural environments enriched in secondary metabolites. We compared patterns of morphological evolution in the size and shape of male wing and genitalia of Drosophila buzzatii and Drosophila koepferae selected for different levels of alkaloid intensities for 20 generations. We found similar modes of selection operating among organs but not among species. The evolution of these traits in D. koepferae were compatible with patterns of stabilizing selection, while in D. buzzatii were characterized by directional changes. We also found that allometric variation was an important component of genital shape evolution, whereas changes in the wing morphology were less pronounced and mostly non-allometric. Overall, our data suggest that the diversification of sexual traits in this species pair is related to the evolution of dissimilar genetic architectures and reinforced by divergent ecological responses. [ABSTRACT FROM AUTHOR]

A new species of ground beetle, Trechisibus (Trechisibiodes) apukhapiensis sp. n. from the Andean Mountains of southeastern Peru is described based on specimens collected in the Apu Khapia Mountain, 4 462 m. (16° 20' 41" S, 68° 08' 57" W), Puno region. This species is externally similar to T. bohorquezae and T. orophilus, yet differs specifically from them in the male genitalia. [ABSTRACT FROM AUTHOR]

The blattid genus Protagonista Shelford, 1908, which is tentatively assigned to the subfamily Archiblattinae (= Planeticinae), is reported from China for the first time with illustrations and description of P. lugubris Shelford, 1908. It is a wood-dwelling and potentially a wood-feeding species. The male and female genitalia of Protagonista are described and illustrated for the first time. The species Protagonista pertristis Hanitsch, 1923 is revived from the synonymy of P. lugubris, and the remaining three nominal species that were also considered as synonyms of P. lugubris are now recognized as synonyms of P. pertristis. In agreement with Princis (1965), we propose that Eroblatta Shelford, 1910, a genus closely related to Protagonista, should be placed in the subfamily Archiblattinae rather than Blattinae. However, the taxonomy of Archiblattinae is problematic and awaits revision. Photos and a key to species of Protagonista and Eroblatta are provided, including photos of the holotypes of the synonymized nominal species. In addition, although Planeticinae is the senior synonym of Archiblattinae, the priority of the latter should be maintained since it is in prevailing usage based on the Article 40.2 in ICZN 4th edition. [ABSTRACT FROM AUTHOR]

A new species of Lachesilla, from the Mexican state of Chiapas, is described and illustrated, it is assigned to species group Corona on basis of the paraprocts, epiproct, and phallosome apodemes; the hypandrium and claspers do not seem to fit well into species group Corona. [ABSTRACT FROM AUTHOR]

Two species of genus Danaus Kluk (1802), Danaus chiysippus Linnaeus (1758) and Demons genutia Cramer (1779), commonly called monarchs, queens and milkweed butterflies are re-described. This re-description is based on coloration of wings, structure of mouthparts, maxillary palpi and internal male and female genitalia. The occurrence of these species of butterflies is new record from Jamshoro, Sindh, Pakistan. [ABSTRACT FROM AUTHOR]

The exaggerated weapons and ornaments of sexual selection are condition-dependent traits that often grow to exaggerated proportions. The horns of male rhinoceros beetles are extremely sensitive to the larval nutritional environment and are used by rival males in combat over access to females. In contrast to horns, other parts of the body, such as wings, eyes, and legs, scale proportionally with body size, whereas others, such as males’ external genitalia, are invariant with body size, regardless of nutrition. We document how body parts of the Asian rhinoceros beetle, Trypoxylus dichotomus, exhibit plasticity and constraint in response to nutritional condition. We discuss the implications of these results for the evolution of condition-dependent and condition-independent traits in animals. [ABSTRACT FROM AUTHOR]

Two new species of Varma Distant, 1906, V. falcata Chang & Chen, sp. n. (China: Guizhou) and V. lobata Chang & Chen, sp. n. (China: Guizhou) are described and illustrated. The female genitalia of four speices including two known species are described and illustrated for the first time. The diagnostic characters of this genus are redefined. A checklist to the species of Varma in China is given. The Keys on male and female genitalia to the Chinese species of Varma are provided. [ABSTRACT FROM AUTHOR]

Abstract: Wolbachia are obligate intracellular bacteria that cause cytoplasmic incompatibility in mosquitoes. In an incompatible cross, eggs of uninfected females fail to hatch when fertilized by sperm from infected males. We used polyacrylamide gel electrophoresis and tandem mass spectrometry to identify Wolbachia proteins in infected mosquito gonads. These included surface proteins with masses of 25 and 18 kDa and the DNA binding protein, HU beta. Using reverse transcriptase polymerase chain reaction, we showed that the HU gene is transcribed in Wolbachia-infected Culex pipiens and Aedes albopictus mosquitoes. We sequenced HU genes from four Wolbachia strains and compared deduced protein sequences with additional homologs from the databases. Among the Rickettsiales, Wolbachia HU has distinct N- and C-terminal basic/acidic amino acid motifs as well as a pair of conserved, cysteine residues. [Copyright &y& Elsevier]

Copyright of SHILAP Revista de Lepidopterologia is the property of Sociedad Hispano-Luso-Americana de Lepidopterologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sexual harassment studies in insects suggest that females can incur several kinds of costs from male harassment and mating. Here, we examined direct and indirect costs of male harassment on components of female fitness in the predominantly monandrous mosquito Aedes aegypti. To disentangle the costs of harassment versus the costs of mating, we held females at a low or high density with males whose claspers were modified to prevent insemination and compared these to females held with normal males and to those held with females or alone. A reduced longevity was observed when females were held under high-density conditions with males or females, regardless if male claspers had been modified. There was no consistent effect of harassment on female fecundity. Net reproductive rate ( R) was higher in females held at low density with normal males compared to females held with males in the other treatments, even though only a small number of females showed direct evidence of remating. Indirect costs and benefits that were not due to harassment alone were observed. Daughters of females held with normal males at high density had reduced longevity compared to daughters from females held without conspecifics. However, their fitness ( R) was higher compared to females in all other treatments. Overall, our results indicate that A. aegypti females do not suffer a fitness cost from harassment of males when kept at moderate densities, and they suggest the potential for benefits obtained from ejaculate components. [ABSTRACT FROM AUTHOR]

Animal genitalia show two striking but incompletely understood evolutionary trends: a great evolutionary divergence in the shape of genitalic structures, and characteristic structural complexity. Both features are thought to result from sexual selection, but explicit comparative tests are hampered by the fact that it is difficult to quantify both morphological complexity and divergence in shape. We undertake a comparative study of multiple nongenitalic and male genital traits in a clade of 15 water strider species to quantify complexity and shape divergence. We show that genital structures are more complex and their shape more divergent among species than nongenital traits. Further, intromittent genital traits are more complex and have evolved more divergently than nonintromittent genital traits. More importantly, shape and complexity of nonintromittent genital traits show correlated evolution with indices of premating sexual selection and intromittent genital traits with postmating sexual selection, suggesting that the evolution of different components of genital morphology are shaped independently by distinct forms of sexual selection. Our quantitative results provide direct comparative support for the hypothesis that sexual selection is associated with morphological complexity in genitalic traits and highlight the importance of quantifying morphological shape and complexity, rather than size in studies of genital evolution. [ABSTRACT FROM AUTHOR]

Abstract: The general structure of the female genital system of Zorotypus caudelli is described. The ovarioles are of the panoistic type. Due to the reduction of the envelope (tunica externa) the ovarioles are in direct contact with the hemolymph like in some other insect groups, Plecoptera included. The calices are much larger in Z. caudelli then in Zorotypus hubbardi and their epithelial cells produce large amounts of secretions, probably protecting the surface of the eggs deposited on the substrate. Eggs taken from the calyx bear a series of long fringes, which are missing in the eggs found in the ovariole, and in other zorapteran species. The long sperm of Z. caudelli and the long spermathecal duct are likely related to a sexual isolating mechanism (cryptic female choice), impeding female re-mating. The apical receptacle and the spermathecal duct - both of ectodermal origin - consist of three cell types. In addition to the cells beneath the cuticle lining the lumen, two other cell types are visible: secretory and canal cells. The cytoplasm of the former is rich in rough endoplasmic reticulum cisterns and Golgi complexes, which produce numerous discrete dense secretory bodies. These products are released into the receiving canal crossing the extracellular cavity of secretory cells, extending over a series of long microvilli. The secretion is transported towards the lumen of the apical receptacle of the spermatheca or to that of the spermathecal duct by a connecting canal formed by the canal cells. It is enriched by material produced by the slender canal cells. Before mating, the sperm cells are enveloped by a thick glycocalyx produced at the level of the male accessory glands, but it is absent when they have reached the apical receptacle, and also in the spermathecal duct lumen. It is likely removed by secretions of the spermatheca. The eggs are fertilized at the level of the common oviduct where the spermathecal duct opens. Two micropyles at the dorsal side of the equator level possibly facilitate fertilization. The presence of these two micropyles is a presumably derived feature shared with Phasmatodea. The fine structure of the female reproductive system of Z. caudelli does not allow to assess the phylogenetic position at the present stage of knowledge. The enlarged calyx and the temporary presence of long fringes on the eggs are potential autapomorphies of Z. caudelli or may indicate relationships with other Zorotypus species. [Copyright &y& Elsevier]

Copyright of SHILAP Revista de Lepidopterologia is the property of Sociedad Hispano-Luso-Americana de Lepidopterologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of SHILAP Revista de Lepidopterologia is the property of Sociedad Hispano-Luso-Americana de Lepidopterologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of SHILAP Revista de Lepidopterologia is the property of Sociedad Hispano-Luso-Americana de Lepidopterologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Longevity is a typical quantitative trait which is influenced by multiple genes. Here we explore the genetic variation in longevity of Drosophila melanogaster in both mildly heat-stressed and control flies. Quantitative trait loci (QTL) analysis for longevity was performed in a single-sex environment at 25°C with and without a mild heat-stress pre-treatment, using a previously reported set of recombinant inbred lines (RIL). QTL regions for longevity in heat-stressed flies overlapped with QTL for longevity in control flies. All longevity QTL co-localized with QTL for longevity identified in previous studies using very different sets of RIL in mixed sex environments, though the genome is nearly saturated with QTL for longevity when considering all previous studies. Heat stress decreased the number of significant QTL for longevity if compared to the control environment. Our mild heat-stress pre-treatment had a beneficial effect (hormesis) more often in shorter-lived than in longer-lived RIL. [Copyright &y& Elsevier]

The Drosophila melanogaster species complex consists of four species: D. melanogaster, D. simulans, D. sechellia and D. mauritiana. To identify these closely related species, researchers often examine the male genitalia, especially species-specific shapes of the posterior process, as the most reliable and easily observable character. However, compared to genetic aspects, the evolutionary significance of the posterior process and other genital parts remains largely unexplained. By comparing genital coupling among these species, we revealed that the posterior processes, which are hidden under the female abdominal tergite VII when genital coupling is established, mesh with different parts of the intersegmental membrane between the tergite VIII and the oviscapts and that this membrane region broadens in a species-specific manner. Furthermore, in D. simulans and D. sechellia, this membrane region is likely to incur wounds from the sharply pointed tip of the posterior process. On the basis of the use and functions of these and other genital parts, we discuss possible evolutionary forces underlying the diversification of genitalia in this group. [ABSTRACT FROM AUTHOR]

Undescribed spermathecae of nine species of Asilidae: Asilinae are illustrated: Anarmostus iopterus (Wiedemann), Dicropaltum rubicundus (Hine), Epipamponeurus americanus Becker, Leinendera rubra Carrera, Lestophonax mallophoroides Hull, Negasilus mesae Tucker, Prolatiforceps anonymus (Williston), Stenasilus tenuis (Wiedemann), and Threnia carbonaria (Wiedemann). Dissections and nomenclature follow Artigas (1971) and Theodor (1976). Specimens used were from the insect collections of the Museo de Zoología, Universidad de Concepción, Chile; Museu de Zoología, Universidade de Sao Paulo, Brazil; and Musée National d´ Histoire Naturelle, Paris, France. Differences and similarities between species are discussed. [ABSTRACT FROM AUTHOR]

Abstract: The photoperiodic response is crucial for many insects to adapt to seasonal changes in temperate regions. It was recently shown that the circadian clock genes period (per) and cycle (cyc) are involved in the photoperiodic regulation of reproductive diapause in the bean bug Riptortus pedestris females. Here, we investigated the involvement of per and cyc both in the circadian rhythm of cuticle deposition and in the photoperiodic diapause of R. pedestris males using RNA interference (RNAi). RNAi of per and cyc disrupted the cuticle deposition rhythm and resulted in distinct cuticle layers. RNAi of per induced development of the male reproductive organs even under diapause-inducing short-day conditions, whereas RNAi of cyc suppressed development of the reproductive organs even under diapause-averting long-day conditions. Thus, the present study suggests that the circadian clock operated by per and cyc governs photoperiodism of males as that of females. [Copyright &y& Elsevier]

Abstract: The cost of sexual interactions, usually expressed as a reduction of life-span, is a fundamental but poorly understood aspect of life. According to a widely accepted view, a rise in the “pro-aging” juvenile hormone (JH) might contribute to the decrease of life span caused by sexual interactions. We tested this hypothesis using the linden bug Pyrrhocoris apterus by removing the corpus allatum (CA), the source of JH. If JH is causally involved in the cost of sexual interactions, then the absence of CA (JH) should decrease the negative effect of sexual interactions on survival. As expected, ablating the CA significantly prolonged life-span of both virgin females and virgin males. Mated insects of both sexes lived significantly shorter than virgins. However, contrary to prediction, the decrease of life span by sexual interactions was similar in control and CA-ablated males, and was even enhanced in CA-ablated females. Another unexpected finding was that males paired with CA-ablated females lived almost as long as virgin males and significantly longer than did males paired with control females, although ablating the female CA did not cause any decrease in mating activity. On the other hand, females paired with CA-ablated males lived only slightly longer than did females paired with control males. These results highlight several important points. (1) In both genders, the negative effect of sexual interactions on insect''s survival is not mediated by the insect''s own CA. (2) The male CA has only minor effect on female survival, while (3) the female CA (JH) is principally responsible for the sex-induced reduction in the male survival. [Copyright &y& Elsevier]

Polymerase chain reaction (PCR)-based methods are increasingly used to elucidate tick biology. However, DNA extracted from ticks may provide poor PCR templates as a result of PCR inhibition by mammalian blood or contamination by male DNA (in fertilized females). In this study, the effects of removing the bloodmeal and reproductive organs were evaluated through paired DNA extractions in engorged and non-engorged Dermacentor variabilis (Say) (Acari: Ixodidae), prior to PCR amplification at 12 microsatellites. The first extraction utilized only mouthparts and legs ('mouthpart' samples) and the second utilized tick bodies ('body' samples). The results indicated that contamination by male DNA was an unlikely source of genotyping error in mouthpart and body samples. Engorged females showed higher levels of PCR inhibition in body vs. mouthpart samples, with a 29% decrease in amplification success rates per PCR and a 10-fold increase in levels of missing genotypes in body samples. By contrast, non-engorged females showed little difference in amplification success rates or numbers of missing genotypes in body vs. mouthpart samples. We discuss analytical concerns related to this systematic bias in PCR problems and recommend the removal of the bloodmeal and reproductive organs prior to DNA extraction, especially in engorged female ticks. [ABSTRACT FROM AUTHOR]

The article presents a study which examines structural aspects of leg-to-gonopod metamorphosis in male helminthomorph millipedes (Diplopoda). Histology methods and confocal laser scanning microscopy were used to study external and internal changes caused by non-systemic metamorphosis for development of gonopod apodemes and extrinsic muscles. The study shows that internal changes in the seventh trunk ring, leads to the dorsal displacement of the ventral nerve cord and the digestive tract.

Two new species of the genus Telephata Meyrick which has been known to be monotypic, T. melanista, sp. nov. and T. ferruginula, sp. nov., are described from Papua New Guinea. A known species from the island, Lecithocera nitens Daikonoff, is transferred to this genus; Telephata nitens (Diakonoff), comb. nov. Keys to the species of Telephata, based on external and genital characters are given, along with illustrations of adults, wing venations, and male genitalia. [ABSTRACT FROM AUTHOR]

Silphinae (Coleoptera: Silphidae) is an abundant decomposer that plays important roles in the ecosystem. However, there is little information about the life history of this taxon. We found sperm displacement behavior in carrion beetle Silpha perforata. Copulating males bit the female's antenna strongly and inserted the penis into the partner's genital organ more than once. We found a white substance on the tip of penis during copulation. We examined whether this white substance is a previous male's spermatophore, which was removed from the mating partner. When females were dissected just after mating, the same substance that often presents on the penis of mating males was found in the bursa copulatrix of females, although the bursa copulatrix of virgin females was empty. Male behavior during copulation with females of different mating history was also observed to confirm that the removal of spermatophores was observed only in copulation with females that have the spermatophores of previous males. Consequently, we estimated that S. perforata males removed spermatophores of previous males from mating partners. In addition, we dissected the males frozen during copulation, and inspected the penis morphology. This observation revealed that the apical part of the penis was usually hidden in the basal part of penis, but expanded and appeared during insertion. This apical part had many spines, which play an important role in sperm displacement and sexual conflict in some species. These results indicate that there is the sperm competition in S. perforata. This is the first report on sperm competition in Silphinae. [ABSTRACT FROM AUTHOR]

The article discusses a study comparing the acrosome fomation in the testicular lobes of the species belonging to the subfamilies Discocephalinae and Pentatominae. It is discussed that the behavior of periodic acid Schiff (PAS) positive granules to mirgrate to one of the extremities of the spermatid was similar in all species. It further demonstrates the differences in the behavior of granules in Antiteuchus tripterus, Euschistus heros and Platycarenus umbractulatus.

The article discusses a study on two species of pirate bugs, Orius insidiosus and Orius pumilio. It is discussed that male and female genitalia, deoxyribonucleic acid (DNA) sequences and the result of their mating were observed to understand the relationship between these species. The study revealed 91 percent homology in the 18S ribosomal sequences while few or no eggs results from interspecific mating which conclude that O. insidiosus and O. pumilio are two separate species.

Abstract: In some insect species, certain substances in the seminal fluid of males induce egg production and laying in females. We determined the effects of male-derived substances on female oviposition behaviour in two Callosobruchus species, C. chinensis and C. maculatus. Aqueous extracts of the accessory gland; testis; and seminal vesicle, including the ejaculatory duct, were prepared. The injection of these extracts into abdomen of females induced oviposition in both species. Oviposition was induced by the testis and seminal vesicle extracts in C. chinensis and by the accessory gland extracts in C. maculatus. The extracts were separated into three fractions by ultrafiltration: fractions I, molecular weight (MW) <3kDa; fraction II, 3–14kDa; and fraction III, >14kDa. Fraction III induced oviposition in both species. These results suggest that in these two species, the substances that induce oviposition have similar MW but are present in different organs. Oviposition was induced by high-MW (>14kDa) substances in the testis and seminal vesicle in C. chinensis, and by high-MW substances in accessory gland in C. maculatus. Here, we have discussed the relationship between oviposition and the abovementioned male-derived substances. [ABSTRACT FROM AUTHOR]

Abstract: Vitellogenin (Vg) and lipophorin (Lp) are lipoproteins which play important roles in female reproductive physiology of insects. Both are actively taken up by growing oocytes and especially Vg and its receptor are considered as female-specifically expressed. The finding that the fat body of in honey bee (Apis mellifera) drones synthesizes Vg and is present in hemolymph has long been viewed as a curiosity. The recent paradigm change concerning the role played by Vg in honey bee life history, especially social division of labor, has now led us to investigate whether a physiological constellation similar to that seen in female reproduction may also be represented in the male sex. By means of Western blot analysis we could show that both Vg and Lp are present in the reproductive tract of adult drones, including the accessory (mucus) glands, but apparently are not secreted. Furthermore, we analyzed the transcript levels of the genes encoding these proteins (vg and lp), as well as their putative receptors (Amvgr and Amlpr) in fat body and accessory glands. Whereas lp, vg and Amlpr transcript levels decreased with age in both tissues, Amvgr mRNA levels increased with age in fat body. To our knowledge this is the first report that vitellogenin and its receptor are co-expressed in the reproductive system of a male insect. We interpret these findings as a cross-sexual transfer of a social physiological trait, associated with the rewiring of the juvenile hormone/vitellogenin circuitry that occurred in the female sex of honey bees. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the effects of injecting male-derived extracts on congeneric female receptivity in two species of Callosobruchus beetle, C. chinensis and C. maculatus. We also examined the influence of interspecific mating on female remating behaviour in these two species. Male-derived extracts reduced congeneric female receptivity in both species. As quick-acting components, extracts of C. chinensis male seminal vesicles reduced the receptivity of C. maculatus females, whereas extracts of C. maculatus male testes reduced the receptivity of C. chinensis females. As slow-acting components, extracts of male accessory glands of other species reduced the receptivity of both C. maculatus and chinensis females. After interspecific mating, the sperm of C. maculatus males were transferred to the reproductive organs of C. chinensis females, thereby reducing their receptivity. In contrast, no C. chinensis sperm were transferred to the reproductive organs of C. maculatus females; accordingly, the latter''s receptivity was not reduced. Furthermore, the survival rate of C. chinensis females decreased markedly after interspecific mating. These results raise the possibility that under circumstances where populations of these two species share the same habitat, reproductive interference would occur only in the interactions between C. maculatus males and C. chinensis females. [Copyright &y& Elsevier]

Cephalopsyche, a new genus of caddisfly (Trichoptera, Odontoceridae), is described from Vietnam. Two new species are placed in the genus: C. gorgona sp. n. and C. neboissi sp. n. Th e adult male and female of each species exhibit distinct sexual dimorphism, especially in head morphology. In males, there are hinged, chamber-like structures on the vertex of the head, containing filamentous, columnar tissue when exposed. Descriptions and illustrations of both species are provided. [ABSTRACT FROM AUTHOR]

Abstract: This study represents the first characterization of male reproductive tracts and ultrastructural description of sperm of Cryptinae species. In Lymeon dieloceri and Pachysomoides sp., the male reproductive tract is formed by a pair of testis, two deferent ducts, two accessory glands and one ejaculatory duct. The spermatozoa are similar to those described for other Hymenoptera, with: (1) the acrosome formed by the acrosomal vesicle covering the perforatorium, which has its base inserted in a cavity located in the nucleus point; (2) a thin nucleus with electron-dense chromatin; (3) an electron-dense centriolar adjunct located between the nucleus and one of the two mitochondrial derivatives; (4) an axoneme with a 9+9+2 microtubule arrangement; (5) two long mitochondrial derivatives with peripheral cristae and; (6) two accessory bodies located between the two mitochondrial derivatives and the axoneme. These ichneumonids present structural characteristics similar to other parasitic wasps, such as presence of a single follicle per testis, layer of extracellular material enveloping the acrosome and accessory microtubules ending before others in final portion of the flagellum. However, male reproductive system and the spermatozoa presented morphological characteristics that allowed their differentiation, such as oval shapes accessory glands and the symmetric mitochondrial derivatives in L. dieloceri compared to the spherical accessory glands and asymmetrical derivatives observed in Pachysomoides sp. Taken together, data presented here demonstrates that diversity of morphological characteristic from the male reproductive tract and spermatozoa in Hymenoptera might provide a character system that can be used, in association with other systems, to resolve various uncertainties about the evolutionary relationships of this insect group. [Copyright &y& Elsevier]

The reproductive division of labour is a key feature of eusociality in ants, where queen and worker castes show dramatic differences in the development of their reproductive organs. To understand the developmental and genetic basis underlying this division of labour, we performed a molecular analysis of ovary function and germ cell development in queens and workers. We show that the processes of ovarian development in queens have been highly conserved relative to the fruitfly Drosophila melanogaster. We also identify specific steps during oogenesis and embryogenesis in which ovarian and germ cell development have been evolutionarily modified in the workers. These modifications, which we call ‘reproductive constraints’, are often assumed to represent neutral degenerations that are a consequence of social evolutionary forces. Based on our developmental and functional analysis of these constraints, however, we propose and discuss the alternative hypothesis that reproductive constraints represent adaptive proximate mechanisms or traits for maintaining social harmony in ants. We apply a multi-level selection framework to help understand the role of these constraints in ant social evolution. A complete understanding of how cooperation, conflict and developmental systems evolve in social groups requires a ‘socio-evo-devo’ approach that integrates social evolutionary and developmental biology. [ABSTRACT FROM AUTHOR]

Although females of the horned beetle, Trypoxylus dichotomus septentrionalis, have only small horns they often fight over access to feeding sites by head-butting each other. In addition, they sometimes show intrasexual mounting. In this study 82 females of different sizes were used to determine the relationship between fighting and mounting. Large females more often won fights and so gained access to food than small females. In contrast, small females more often mounted large females and then gained access to food than large females. These results suggest that female mounting may function as a tactic for reducing intrasexual fighting between small and large females. [ABSTRACT FROM AUTHOR]

The housefly, Musca domestica, is an excellent model system to study the diversification of the pathway that specifies the sexual fate. A number of different mechanisms have been described in the housefly, which reflects in part the broad diversity of sex-determining strategies used in insects. In this study we present the molecular identification and characterization of F, which acts as the master switch in the housefly pathway. We provide evidence that F corresponds to the transformer ortholog in Musca (Mdtra), which, as a result of alternative processing, expresses functional products only in individuals committed to the female fate. We demonstrate that, once activated, a self-sustaining feedback loop will maintain the female-promoting functions of Mdtra. Absence of Mdtra transcripts in eggs of Arrhenogenic (Ag) mutant females suggests that maternally deployed Mdtra activity initiates this self-sustaining loop in the zygote. When an M factor is paternally transmitted to the zygote, the establishment of the loop is prevented at an early stage before cellularization and splicing of Mdtra shifts irreversibly to the male nonproductive mode. On the basis of the analysis of two mutant alleles we can explain the different sex-determining systems in the housefly largely as deviations at the level of Mdtra regulation. This plasticity in the housefly pathway may provide a suitable framework to understand the evolution of sex-determining mechanisms in other insect species. For instance, while sex determination in a close relative, the tsetse fly Glossina morsitans, differs at the level of the instructive signal, we find that its tra ortholog, Gmtra, is regulated in a mode similar to that of Mdtra. [ABSTRACT FROM AUTHOR]

Abstract: A possible explanation for one of the most general trends in animal evolution – rapid divergent evolution of animal genitalia – is that male genitalia are used as courtship devices that influence cryptic female choice. But experimental demonstrations of stimulatory effects of male genitalia on female reproductive processes have generally been lacking. Previous studies of female reproductive physiology in the tsetse fly Glossina morsitans suggested that stimulation during copulation triggers ovulation and resistance to remating. In this study we altered the form of two male genital structures that squeeze the female''s abdomen rhythmically in G. morsitans centralis and induced, as predicted, cryptic female choice against the male: sperm storage decreased, while female remating increased. Further experiments in which we altered the female sensory abilities at the site contacted by these male structures during copulation, and severely altered or eliminated the stimuli the male received from this portion of his genitalia, suggested that the effects of genital alteration on sperm storage were due to changes in tactile stimuli received by the female, rather than altered male behavior. These data support the hypothesis that sexual selection by cryptic female choice has been responsible for the rapid divergent evolution of male genitalia in Glossina; limitations of this support are discussed. It appears that a complex combination of stimuli trigger female ovulation, sperm storage, and remating, and different stimuli affect different processes in G. morsitans, and that the same processes are controlled differently in G. pallidipes. This puzzling diversity in female triggering mechanisms may be due to the action of sexual selection. [Copyright &y& Elsevier]

The species belonging to the genus Metahelotella Kirejtshuk are revised. Six species are recognized, including two described herein, M. schawalleri sp. nov. from Vietnam and M. sprecherae sp. nov. from China (Shaanxi Province). Helotafulvitarsis Ritsema and H. difficilis Ritsema are placed as junior synonyms of M. semifulva Ritsema. Lectotypes are designated for H. fulvitarsis Ritsema, H. difficilis Ritsema, and H. immaculata Ritsema. A key and diagnosis of the species belonging to the genus Metahelotella Kirejtshuk are provided. Figures of protibiae, genitalia, internal sacs, eighth abdominal tergites, and fifth abdominal ventrites are given for all species. [ABSTRACT FROM AUTHOR]

The article presents a study which describes the characteristics of a new identified specie Zelandobius edensis, which was found in headwaters of the Rangitata River catchment in South Canterbury, New Zealand. The measurement and description of the specie was assessed by magnification dissecting microscope. An overview of the features of the specie including its genitalia are presented. Moreover, it discusses the difference of Zelandobius endensis with other species under the Zelandobius genus.

Background: Insect ovarioles are classified into two categories: panoistic and meroistic, the later having apparently evolved from an ancestral panoistic type. Molecular data on oogenesis is practically restricted to meroistic ovaries. If we aim at studying the evolutionary transition from panoistic to meroistic, data on panoistic ovaries should be gathered. To this end, we planned the construction of a Suppression Subtractive Hybridization (SSH) library to identify genes involved in panoistic choriogenesis, using the cockroach Blattella germanica as model. Results: We constructed a post-vitellogenic ovary library by SSH to isolate genes involved in choriogenesis in B. germanica. The tester library was prepared with an ovary pool from 6- to 7-day-old females, whereas the driver library was prepared with an ovary pool from 3- to 4-day-old females. From the SSH library, we obtained 258 high quality sequences which clustered into 34 unique sequences grouped in 19 contigs and 15 singlets. The sequences were compared against non-redundant NCBI databases using BLAST. We found that 44% of the unique sequences had homologous sequences in known genes of other organisms, whereas 56% had no significant similarity to any of the databases entries. A Gene Ontology analysis was carried out, classifying the 34 sequences into different functional categories. Seven of these gene sequences, representative of different categories and processes, were chosen to perform expression studies during the first gonadotrophic cycle by real-time PCR. Results showed that they were mainly expressed during post-vitellogenesis, which validates the SSH technique. In two of them corresponding to novel genes, we demonstrated that they are specifically expressed in the cytoplasm of follicular cells in basal oocytes at the time of choriogenesis. Conclusion: The SSH approach has proven to be useful in identifying ovarian genes expressed after vitellogenesis in B. germanica. For most of the genes, functions related to choriogenesis are postulated. The relatively high percentage of novel genes obtained and the practical absence of chorion genes typical of meroistic ovaries suggest that mechanisms regulating chorion formation in panoistic ovaries are significantly different from those of meroistic ones. [ABSTRACT FROM AUTHOR]

The European honeybee, Apis mellifera, has been introduced to all continents and their products like honey, propolis, royal jelly and beeswax are well known. However, its contribution is not restricted to such direct products but extends into a much wider area. For example, the economic value of seed production by pollination exceeds the above-mentioned bee products. The application of F1 hybrid is increased to as much as 70% of commercial crops and flowers in Japan and honeybees are important pollinators in the F1 seed production. Incorporation into the large-scale biodiesel fuel production system by culturing rape and sunflower seeds etc. is relied on because it is good to construct possible zero-emission systems that reduce carbon dioxide and increase the rich by-products like honey and royal jelly. Bees’ higher brain function and sophisticated social system of the colony opens new perspectives as a model system. Their individual ability to recognize even abstract concepts is comparable to that of higher primates. Rats or mice have no such ability. High performance learning ability of bees associated with proboscis extension reflex can be used to detect drugs at the airport. Function of the colony, on the other hand, is an excellent model for social physiology or a self-organization system. After the whole genome of A. mellifera was read in 2006 by the world consortium, consisting of more than 90 institutions from all over the world, many molecular biologists are coming into bee world. Nobody has yet succeeded in the challenge to make transgenic honeybee, so far, because of the difficulty in controlling the reproductive system headed by the queen. However, if someone succeeded in a breakthrough we will have stingless honeybees and a disease-resistant strain in the future. [ABSTRACT FROM AUTHOR]

Female genitalia of insects are formed by several structures whose functions are poorly understood. The signa are sclerotized structures located on the inner wall of the corpus bursa of females of many Lepidoptera species, In this paper, we first describe seven hypotheses concerning the function of signa and derive several predictions from them. Then, we test several of these hypotheses with studies of four butterfly species (Callophrvs xami Reakirt, Eueides isabella Cramer, E. lineata Salvin & Godman, and Heliconius ismenius Doubleday) and conclude that in these species signa are mainly used for breaking the envelope of spermatophores. These results are in agreement with the idea that signa ,are a product of sexual coevolution. [ABSTRACT FROM AUTHOR]

Male structures for clasping females during precopula interactions and mating (“claspers”) have evolved in many groups of arthropods. Several hypotheses regarding the function of claspers have been proposed. We describe how males of the true bug Stenomacra marginella (Heteroptera: Largidae) move their genital claspers during sexual interactions, and present the results of experiments in which we tested whether claspers are necessary to achieve intromission. When one and both claspers were partially amputated, the probability of successful intromission decreased from 62 to 0% and from 57 to 3%, respectively. Behavioral observations indicate that the claspers open the valves that cover the female genital opening. We consider the possibility that claspers in S. marginella may have multiple functions. [ABSTRACT FROM AUTHOR]

The oviposition process of the red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), is described as a succession of four events forming one egg-laying cycle. Each time an egg is laid, the vulva opens and the sting is fully extended. When the vulva closes, the egg is forced to the base of the sting, whereupon the sting is usually retracted across the egg. This phenomenon has been consistently observed for queens from monogynous and polygynous S. invicta colonies. Zero to four eggs can be laid for each opening of the vulva. Multiple egg deposition is more frequent for monogyne queens, and it generally follows an oviposition cycle in which no egg is laid. The egg-laying cycles were evenly distributed during the observation periods, regardless of the total number of eggs laid, thereby suggesting that oviposition is a continuous process in S. invicta. [ABSTRACT FROM AUTHOR]

In two previous articles, we reported that the male genitalia of six species of Parabrochymena and 14 species of Brochymena were distinct, particularly the shape and length of the vesica, thus supporting the establishment of Parabrochymena. Here, we present genitalic and nongenitalic information on four of the remaining five species of these two genera. Because of the results of these analyses, and in combination with similar analyses of species described earlier, we have transferred three of the four species [i.e., Parabrochymena enigmatica (Ruckes), Parabrochymena inbio Larivère, and Parabrochymena poeyi (Guérin-MéNeville)] to Brochymenta. Also, we have provided descriptions of Brochymena and Parabrochymena and the New World tribe (Halyini), which includes only these genera. [ABSTRACT FROM AUTHOR]

Primary reproductives of the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), complete their first reproductive cycle in ≈60 d after nest formation. During this period, the pairs mate several times. The spherical, aflagellate sperm, after transfer by the male, are stored in the female's spermatheca. Sperm numbers in the spermatheca increase significantly between day 20 and 40, and thereafter they show a steep decline, indicating that the pairs may not be mating after day 40. The spermatheca is bean shaped with an extremely narrow duct. The thick wall of the spermatheca consists mainly of type 3 cells made up of secretory and duct cells. Cuticle-lined ducts are interspersed throughout these cells. Finger-like extensions of the cuticle-lined interior wall project into the spermathecal lumen. The secretory cells presumably provide nutrition for the sperm during their long storage. Eleven anaerobic and six aerobic species of bacteria were cultured and identified from the spermatheca. The role of these bacteria is unknown. [ABSTRACT FROM AUTHOR]

Anthocoris antevolens White (Hemiptera: Heteroptera: Anthocoridae) is a widespread predatory bug in North America that exhibits substantial geographic variation in coloration, body measurements, size and shape of the male genitalia, pubescence, and sexual behavior. Earlier behavioral studies with three populations (including two populations that are sympatric in central Washington) showed that there was limited or no successful mating between insects from nonlike populations, despite vigorous mating attempts by males. The current study shows that males from those three populations diverge also in size and shape of claspers, length of the phallus, body measurements, and pubescence. Divergence extends to the two sympatric populations. Analysis of mitochondrial DNA shows that phenotypic divergence is associated with genetic divergence. Results reported here, in combination with the earlier published mating trials, support statements made elsewhere by us that A. antevolens is actually a complex of an unknown number of externally similar species. [ABSTRACT FROM AUTHOR]

Male genital morphology in insects and arachnids is characterized by static hypoallometry and low intrapopulational levels of phenotypic variation relative to other male traits. The one-size-fits-all model of genital evolution attributes these patterns to stabilizing sexual selection. This model relies on the assumption that the observed patterns of variation and allometry reflect the form of sexual selection acting these traits. We test this by examining the patterns of scaling and trait variation for a set of genitalic and somatic morphological traits in male water striders (Aquarius remigis). This suite of traits is of particular interest because previous work has shown that the genitalic traits are under strong directional selection whereas the somatic traits are under either weak directional or stabilizing selection. Because the selection regime for these traits is known, we can, for the first time, test the purported relationship between trait variation, scaling, and the form of sexual selection. We show that the patterns of variation and scaling of these traits differ sharply from those predicted for traits experiencing strong directional sexual selection. Specifically, the male genital structures show static hypoallometry and low intrapopulational levels of phenotypic variation relative to other male traits, in spite of consistent, strong, directional sexual selection. These scaling relationships and levels of variation are typical of genital traits in other insect species, where they have been presumed to reflect stabilizing sexual selection. Our data clearly refute the assumption of the one-size-fits-all hypothesis that hypoallometric scaling of genitalic traits implies stabilizing selection. We discuss the implications of this finding and propose future directions for improving our current understanding of genital evolution in arthropods. [ABSTRACT FROM AUTHOR]

The insecticidal activity of a cockroach gel bait containing a chitin synthesis inhibitor, noviflumuron, was evaluated using laboratory and field strains of the German cockroach, Blattella germanica (L.). Noviflumuron gel bait (0.01-5mg g-1) caused ⩾90% nymphal mortality to laboratory and field strains of B. germanica in choice tests after 11 and 19 days of continuous exposure respectively. In 1m × 1m bioassay arenas, laboratory strain B. germanica population levels exposed to 5mgg-1 noviflumuron bait or 0.1 mgg-1 fipronil gel bait were significantly lower than untreated population levels after 3 weeks and 1 week of exposure respectively. Various novifiumuron bait exposure periods (2, 4 and 7 weeks) caused similar population reductions, with a mean of 99.3 (±0.3)% at 7 weeks. Fipronil gel bait caused 100% population reduction at 2 weeks post-exposure. The control population increased 89.0% at 7 weeks. In a simulated kitchen experiment with mixed stage laboratory populations, cockroach trap catches decreased 96.8 (±2.0)% at 8 weeks in the 0.5mgg-1 noviflumuron bait treatment. The trap catches in the control increased 506.5 (±493.7)% during the same period. Trap catch reduction by 0.1 mgg-1 fipronil gel bait reached 100% at 4weeks. Novifiumuron bait caused significantly lower nymph/total ratios to B. germanica populations in bioassay arenas from 2 weeks after exposure, demonstrating its effectiveness as a control agent for B. germanica with a pattern of activity similar to that expected from a chitin synthesis inhibitor. [ABSTRACT FROM AUTHOR]

Flea beetles of alligator weed, Alternanthera philoxeroides (Martius) Grisebach (Amaranthaceae), were collected in Argentina, Uruguay, Paraguay, and Brazil. Species in the genera Disonycha Chevrolat, Agasicles Jacoby, and Systena Chevrolat were frequently found on this weed. Systena nitentula Bechyné 1954 was the most abundant within Systena. This species is reported for the first time from Argentina at north of 30° S. The male is described and holotype female is redescribed adding new diagnostic characters: mouthparts, hind wings, metendosternite, and male and female genitalia. S. nitentula is recognized by the combined characters of piceous elytra with J-shaped vittae, a small spermatheca pump, and internal median lobe sac with five sclerotized plates. Differences in color patterns between S. nitentula, S. tenuis Bechyné, and S. s-littera L. also are considered. S. nintentula presents three instars that can be separated through head width. New biological data based on laboratory rearing and field observations shows that S. nintentula could be a monophagous species strongly associated to the alligator weed growing in terrestrial conditions. This information promotes S. nintentula as a potential biocontrol agent of this invasive weed. [ABSTRACT FROM AUTHOR]

The new deltocephaline leafhopper genus Oxycephalotettix is described and illustrated based one species, Oxycephalotettix tiputini sp. nov., from Ecuador, and is placed in Athysanini. The genus bears a superficial resemblance to Luheria Osborn (Luheriini), especially in the coloration of the forewing. Based on the examination of type material, Luheria constricta Osborn is herein considered a senior synonym of Tenucephalus hamatus DeLong, new synonymy. The female genitalia of L. constricta are illustrated for the first time, and the known range of this species is expanded to include Bolivia, northern Argentina, and northeastern Brazil. [ABSTRACT FROM AUTHOR]