Ant-like Traits in Wingless Parasitoids Repel Attack from Wolf Spiders.

Area of Science:

• * Insect Ecology
• * Chemical Ecology
• * Predator-Prey Interactions

Background:

• * The wingless parasitoid Gelis agilis displays ant-like traits, repelling wolf spiders.
• * G. agilis secretes 6-methyl-5-hepten-2-one (sulcatone), a known ant alarm pheromone.

Purpose of the Study:

• * To investigate sulcatone production in four Gelis parasitoid species.
• * To assess spider predation susceptibility to these species using two-species choice bioassays.

Main Methods:

• * Chemical analysis for sulcatone presence in four Gelis species, Acrolyta nens, and Cotesia glomerata.
• * Two-species choice bioassays with wolf spiders presenting different parasitoid combinations.

Main Results:

• * All four tested Gelis species produced sulcatone; A. nens and C. glomerata did not.
• * Wolf spiders strongly rejected wingless Gelis species, preferring A. nens and C. glomerata.
• * Spiders showed no preference between A. nens and winged G. areator, but preferred C. glomerata over A. nens.

Conclusions:

• * Wingless Gelis species' ant-like traits likely deter spider predation.
• * Winged G. areator's resemblance to other winged species hinders spider discrimination.
• * Non-sulcatone producing cryptines may possess other anti-predatory traits, suggesting convergent evolution of defense mechanisms.