Courtship behavior in relation to the female sex pheromone in the parasitoid, Aphidius ervi (Hymenoptera: Braconidae).

Mating in the aphid parasitoid, Aphidius ervi, is mediated by sex pheromones. Virgin females produce pheromones that stimulate both upwind flight and elicit close-range courtship behavior by males. Field studies and laboratory bioassays demonstrated that time of day and adult age affect both the emission of, and receptivity to, the sex pheromones. In contrast, mating affected female pheromone production, but not male responsiveness.

Mity model: Tetranychus urticae, a candidate for chelicerate model organism.

Chelicerates (scorpions, horseshoe crabs, spiders, mites and ticks) are the second largest group of arthropods and are of immense importance for fundamental and applied science. They occupy a basal phylogenetic position within the phylum Arthropoda, and are of crucial significance for understanding the evolution of various arthropod lineages. Chelicerates are vectors of human diseases, such as ticks, and major agricultural pests, such as spider mites, thus this group is also of importance for both medicine and agriculture. The developmental genetics of chelicerates is poorly understood and a challenge for the future progress for many aspects of chelicerate biology is the development of a model organism for this group. Toward this end, we are developing a chelicerate genetic model: the two-spotted spider mite Tetranychus urticae. T. urticae has the smallest genome of any arthropod determined so far (75 Mbp, 60% of the size of the Drosophila genome), undergoes rapid development and is easy to maintain in the laboratory. These features make T. urticae a promising reference organism for the economically important, poorly studied and species-rich chelicerate lineage.