A laboratory study investigated development of teratocytes derived from the parasitoid Microctonus aethiopoides Loan in the natural host, Sitona discoideus Gyllenhal, and in three novel hosts, the introduced weed biological control agent Rhinocyllus conicus (Froehlich), and two New Zealand native species Nicaeana cervina Broun and Irenimus stolidus Broun. Weevils were exposed to parasitoids and...

Eretmocerus eremicus is the most abundant parasitoid of the Bemisia complex in North America. It can parasitize equally successfully the most common whiteflies in greenhouses, Trialeurodes vaporariorum and the Bemisia complex. The parasitoid is used in Europe for whitefly control, either alone or in combination with releases of Encarsia formosa. Life-cycle and demographic parameters of this par...

Eggs of the eucalyptus longhorned borer (Phoracantha semipunctata F.) are the typical host of the encyrtid egg parasitoid Avetianella longoi Siscaro. Both P. semipunctata and Phoracantha recurva Newman have become established in California, but A. longoi appears to differentially parasitize these congeners. Eggs of the two beetle species were tested for ovipositional and developmental suitabili...

Communities of insect herbivores are thought to be structured mainly by indirect processes mediated by shared natural enemies, such as apparent competition. In host-parasitoid interaction networks, overlap in natural enemy communities between any pair of host species depends on the realized niches of parasitoids, which ultimately depend on the foraging decisions of individuals. Optimal foraging...

In a natural community of 49 species (12 species of aphids and 37 species of their parasitoids), body lengths of 2,151 parasitoid individuals were, to an excellent approximation, related to the body lengths of their individual aphid hosts by a power law with an exponent close to 3/4. Two alternative models predict this exponent. One is based on surface area to volume relationships. The other is...

Evidence from grassland experiments suggests that a plant community's phylogenetic diversity (PD) is a strong predictor of ecosystem processes, even stronger than species richness per se This has, however, never been extended to species-rich forests and host-parasitoid interactions. We used cavity-nesting Hymenoptera and their parasitoids collected in a subtropical forest as a model system to t...

Successful parasitism of some endoparasitic wasps depends on an obligately symbiotic association with polydnaviruses. These unique viruses have a segmented genome consisting of circles of double-stranded (ds) DNA and do not replicate in the parasitized host. They are produced in the wasp's ovary and injected into the host along with the egg. Chelonus inanitus is an egg-larval parasitoid; its po...

Metamorphosing insects often have complex and poorly known life histories. In particular, what they feed on during their larval stages remains unknown for the vast majority of species, and its documentation only results from difficult and time-intensive field observations, rearing or dissections. Through the application of a DNA analysis of gut contents in adult parasitoid wasps, we were able t...

Variation of host quality affects population dynamics of parasitoids, even at the landscape scale. What causes host quality to vary and the subsequent mechanisms by which parasitoid population dynamics are affected can be complex. Here, we examine the indirect interaction of a plant pathogen with a parasitoid wasp. Under laboratory conditions, parasitoids from hosts fed fungus-infected plants w...

The inhabitants of the bush lupine in coastal California have been the subject of scientific scrutiny in recent years. Observations of a host-parasitoid interaction in the shrub's foliage, in which victims are significantly less motile than their exploiters, record stable spatial patterns in a fairly homogeneous environment. Though such pattern formation has been found in reaction-diffusion mod...