1. Generalist natural enemies are usually not considered as being capable of causing population cycles in forest insects, but they may influence the population dynamics of their prey in the low density cycle phase when specialist enemies are largely absent. 2. In the present field study, the total response of the generalist invertebrate predator community to experimentally established pupal den...

This paper reports the first occurrence of the parasitoid Spalangia endius collected in pupae of Zaprionus indianus using traps with fruit bait. The experiment was carried out at the University of Lavras in Lavras, Minas Gerais, Brazil, from November to December, 2001. A total of 4 Spalangia endius specimens were obtained from 105 Zaprionus indianus pupae. The overall prevalence of parasitism w...

Recent honey bee colony losses, particularly during the winter, have been shown to be associated with the presence of both ectoparasitic mites and Deformed Wing Virus (DWV). Whilst the role of Varroa destructor mites as a viral vector is well established, the role of Tropilaelaps mercedesae mites in viral transmission has not been fully investigated. In this study, we tested the effects that V....

This study was conducted to determine sex differentiation of laboratory reared Elm nymphalid (Nymphalis polychloros Linnaeus, 1758) by examining the morphological structure of pupal stage. Laboratory colony of elm nymphalid, reared on pear leaves, was used to set up experiments. It was performed with 5 replications having 8 pupae for each replication. Dorsal, ventral and lateral parts of extern...

Diapause is an important escape mechanism from seasonal stress in many insects. A certain minimum amount of time in diapause is generally needed in order for it to terminate. The mechanisms of time-keeping in diapause are poorly understood, but it can be hypothesized that a well-developed neural system is required. However, because neural tissue is metabolically costly to maintain, there might ...

Using the Burr-Lane-Nims2 microvoltmeter, Burr and Hovland' have shown that there is a gradual increase in the electrical potential of chick embryos during incubation. With an instrument which differs slightly from that of Burr, and by placing the electrodes farther from the growing embryo, Romanoff and Cottrell4 obtained comparable results. In 1932 Burr formulated the theory that "the pattern ...

The first occurrence of the parasitoid Pachycrepoideus vindemiae on pupae of Ophyra aenescens, a fly of medical-sanitary importance, is reported. A swine carcass was used as bait to collect the insects. In the study, 302 pupae of Ophyra aenescens (Wiedemann) (Diptera: Muscidae) were obtained, 6 (1.98%) of them yielded the parasitoid Pachycrepoideus vindemiae (Hymenoptera: Pteromalidae

Three new species of the genus Parorthocladius Thienemann, P. lazovskiensis sp. nov., P. plolabius sp. nov., and P. tyurkini sp. nov. from the Russian Far East are described and figured. Descriptions of pupae and larvae of one indeterminate species, Parorthocladius sp. 1, are also presented. Keys to determination of adult males, pupae and fourth instar larvae of Far-Eastern species Parorthoclad...

The previously unknown pupa of Heterostomus curvipalpis Bigot is described. The morphology of the pupa of Heterostomus is compared with the pupae of Xylophagomorpha, Tabanomorpha and Stratiomyomorpha families, based on five characters, and its phylogenetic position is discussed. Currently placed in Xylophagidae, we conclude that the pupa of Heterostomus shares most characters with the pupae of ...