Cortejo y cópula en la broca de la semilla de guanábana Bephratelloides pomorum (Hymenoptera: Eurytomidae)

Adults of soursop seed borer Bephratelloides pOlllorum (Hymenoplera: Eurytomidae) were collected from fruits in Maceió, State of Alagoas, Brazil. The courtship and copulatíon behaviours of B. pomorum were described under 27.6 ± O.loC, R.H. of 77 .50 ± 0.8%. A virgin couple of B. pomorum was placed daily in a glass cage for observing lhe courtship and coplllation behaviour during a period of 12 days. This procedllre was repealed ten times by using grollps of 10 to 12 virgin couples per replicate. The observations fol' each replicate wel'e ended after lhe first copulation. In general, males emerged first and newly emerged females elicited male courtship and mating behaviours. The behavioural patterns of males consisted of well-defined sequences such as approaching to female, wing fanning, regulatory body movements, copulation. rubbing aedeago on female abdome, antennae and mOllthparts grooming

Sexy Mouth Odour? Male Oral Gland Pheromone in the Grain Beetle ParasitoidLariophagus distinguendus(Förster) (Hymenoptera: Pteromalidae)

Throughout the animal kingdom, sexual pheromones are used for the attraction of mates and as courtship signals but also enable sexual isolation between species. In the parasitic waspLariophagus distinguendus, male courtship behaviour consisting of wing fanning, antennal stroking of the female antenna, and head nodding stimulates female receptivity leading to copulation. RecentlyL. distinguenduswas reported to consist of two different lineages, which are sexually isolated because males fail to elicit receptivity in foreign females. It is unclear, however, which part of the courtship behaviour triggers female receptivity and therefore could be a mechanism causing sexual isolation. Here we show that inL. distinguendusa nonvolatile male oral pheromone is essential to release the female receptivity signal. In contrast, male wing fanning and antennal contact play a minor role. Additionally, the composition of the oral pheromone depends on the developmental host and females learn the composition upon emergence from the host substrate. These results will enable more detailed work on oral sexual pheromones to answer the question of how they are involved in the speciation process ofL. distinguendusand other parasitoid species, for a better understanding of the huge biodiversity in this group.

Evidence for divergence in cuticular hydrocarbon sex pheromone between California and Mississippi (United States of America) populations of bark beetle parasitoid Roptrocerus xylophagorum (Hymenoptera: Pteromalidae)

Roptrocerus xylophagorum (Ratzeburg) (Hymenoptera: Pteromalidae) is a common Holarctic parasitoid of the larvae and pupae of bark beetles (Coleoptera: Curculionidae: Scotytinae). In no-choice laboratory bioassays, we found that male wasps derived either from northern California or southwestern Mississippi, United States of America more frequently displayed sexual behaviours (including mounting, wing fanning, and copulation attempts) to glass bulb decoys treated with hexane cuticular washes of females derived from the same parasitoid population rather than the distant population. This result suggests that the composition of the cuticular hydrocarbon sex pheromone has diverged between eastern and western populations and is consistent with previous data indicating that R. xylophagorum may consist of more than one species.

The courtship song of fanning males in the fruit fly parasitoid Psyttalia concolor (Szépligeti) (Hymenoptera: Braconidae)

In this paper we describe acoustically the wing-fanning behaviour showed by the male of the braconid Psyttalia concolor towards females and other conspecific males. Psyttalia concolor is a synovigenic koinobiont larval–pupal endoparasitoid of many Tephritidae, used in olive crops to control the olive fruit fly, Bactrocera oleae. In this braconid male wing fanning produces a courtship song characterised by sequences of homogenous pulses with harmonic structure and a fundamental frequency of about 180 Hz. Song parameters can vary according to the behavioural context. Statistically significant differences, both in terms of pulse frequency and duration, characterise fanning towards females in comparison with male–male approaches. Moreover, the pulse duration is associated with the fanning song displayed before a successful courtship. Our observations allowed us to define the airborne component of the sound and to definitely confirm the exclusive role of the wings in signal production within sexual communication in P. concolor.