Search results for "HETEROPTERA"
showing 10 items of 170 documents
Vitellogenesis inhibition in Oncopeltus fasciatus females (Heteroptera: Lygaeidae) exposed to cadmium
2005
Abstract Newly moulted females of the insect Oncopeltus fasciatus were exposed to cadmium (Cd) dissolved in the drinking water (50–400 mg l −1 Cd) for 5 days. Cd exposure delayed ovarian maturation and inhibited egg production. Exposure to Cd, moreover, decreased hemolymph levels of the two major vitellogenin polypeptides of O. fasciatus , VG1 and VG2, in a concentration-dependent way, probably by a reduction in their synthesis. The ovarian levels of VG1 and VG2 were also decreased in Cd-exposed females. It was next investigated whether Cd effects might be a consequence of the endocrine disruption of vitellogenin synthesis, which is controlled by juvenile hormone (JH). JH replacement therap…
Ovicidal Activity of Maternally Applied Ecdysteroids in the Large Milkweed Bug (Heteroptera: Lygaeidae)
1982
Exogenous ecdysteroids (ecdysone, 20-hydroxyecdysone and makisterone A) administered to reproducing females of Oncopelus fasciatus (Dallas) reduced egg hatch drastically. The ovicidal activity apparently stemmed from ecdysteroids—unchanged hormone or metabolites—transferred from mother into oocyte. Different stages of embryogenesis were affected. Makisterone A, the predominant ecdysteroid in normal embryos, is by far the most effective ecdysteroid.
Inter and intra-guild interactions in egg parasitoid species of the soybean stink bug complex
2002
Abstract – The objective of this research was to evaluate the parasitism behavior of Telenomus podisiAshmead, Trissolcus basalis (Wollaston) e Trissolcus urichi Crawford (Hymenoptera: Scelionidae) oneggs of Nezara viridula L., Euschistus heros F., Piezodorus guildinii Westwood and Acrosternumaseadum Rolston (Heteroptera: Pentatomidae), in no choice and multiple choice experiments. For allparasitoid species, the results demonstrated the existence of a main host species that maximizes thereproductive success. The competitive interactions among the parasitoid species were investigated inexperiments of sequential and simultaneous release of different combinations of parasitoid pairs on thehosts…
Macroscytus raunoi, a new burrower bug species from Papua New Guinea (Hemiptera: Heteroptera: Cydnidae: Cydninae)
2016
Abstract Macroscytus raunoi, a new species of the genus Macroscytus Fieber, 1860, is described from the Morobe Province on the northern coast of Papua New Guinea. The new species is similar in its morphological characters to Australian M. arnhemicus J. A. Lis, 1999. Differences in morphology and male genitalia which enable separation of both species are provided.
Taxonomic review of the
2017
Abstract Two new species of the genus Fulvius Stål are described from the Philippines and Papua New Guinea. A taxonomic review of representatives of the F.bifenestratus species group, illustrations of the male genitalia, a color habitus image of each species, and a key to species of the group are provided.
Geotomus granulosus, a peculiar sehirine-like new species of the subfamily Cydninae (Hemiptera: Heteroptera: Cydnidae) from Burundi
2022
Geotomus granulosus sp. n. is described from Burundi, and is the third burrower bug species recorded hitherto from this country. This burrower bug resembles species of two Sehirinae genera, i.e. Ochetostethus Fieber, 1860 and Ochetostethomorpha Schumacher, 1913, in its dorsal body habitus. However, all its crucial diagnostic characters (the body chaetotaxy, the shape of evaporatoria and the peritreme, the meso- and metathoracic wings venation, and the shape of spermatheca) demonstrate it represents the genus Geotomus Mulsant et Rey, 1866 (subfamily Cydninae, tribe Geotomini sensu lato).
Role of volatile and contact pheromones in the mating behaviour of Bagrada hilaris (Heteroptera: Pentatomidae)
2008
Volatiles and contact pheromones involved in the mating behaviour of the Painted bug, Bagrada hilaris Burmeister (Het- eroptera: Pentatomidae), were investigated in behavioural and chemical experiments. Vertical open Y-shaped olfactometer bioassays showed that odour from males attract females but not males, while that from females did not attract either gender. Adult females were also attracted by hexane extracts of volatile compounds collected from males. In open arena bioassays, males displayed the characteristic steps of courtship behaviour in the presence of virgin females. Such courtship behaviour was displayed in the presence of females killed by freezing, but not in the presence of f…
The ovipositing female of Ooencyrtus telenomicida relies on physiological mechanisms to mediate intrinsic competition with Trissolcus basalis
2012
Ongoing studies by our group showed that the outcome of the intrinsic competition between two solitary egg parasitoids, Trissolcus basalis (Wollaston) (Hymenoptera: Scelionidae) and Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae), is dominated by O. telenomicida. In this article we investigated the role played by the ovipositing O. telenomicida female in the suppression of a T. basalis competitor. Laboratory experiments were conducted by allowing an O. telenomicida female to puncture the eggs of Nezara viridula (L.) (Heteroptera: Pentatomidae) with her ovipositor (= no oviposition) or to parasitize them. The results show that O. telenomicida relies on some physiological mechan…
Partially disarticulated new Miocene burrower bug (Hemiptera: Heteroptera: Cydnidae) from Cerová (Slovakia) documents occasional preservation of terr…
2015
The state of preservation of the bug Sehirus carpathiensis J.A. Lis, Vršanský & Schlögl, sp. n. (Hemiptera: Heteroptera: Cydnidae) from the Lakšárska Nová Ves Formation at Cerová (Slovakia) supports extremely rapid sinking and burial in upper bathyal Early Miocene sediments. The specimen originated from land at most a few kilometers away, but transport via a river can be excluded as the head and wings are still attached. Its most likely source based on fossil flora and the habitat of several living representatives of the genus is a riparian habitat in an adjacent area of land. Phylogenetically the new species is closely related to both Oligocene and living representatives of the genus, thus…
Diversity in warning coloration: selective paradox or the norm?
2019
Aposematic theory has historically predicted that predators should select for warning signals to converge on a single form, as a result of frequency-dependent learning. However, widespread variation in warning signals is observed across closely related species, populations and, most problematically for evolutionary biologists, among individuals in the same population. Recent research has yielded an increased awareness of this diversity, challenging the paradigm of signal monomorphy in aposematic animals. Here we provide a comprehensive synthesis of these disparate lines of investigation, identifying within them three broad classes of explanation for variation in aposematic warning signals: …