HOW TO BE A GOOD NON-POLLINATING FIG WASP: GALLING WASPS (Idarnes group flavicollis) DO NOT INTERFERE WITH THE FLORAL RECEPTIVITY

Abstract

Mutualistic relationships are open to exploitation by non-cooperative species that can reduce the fitness of one or both cooperating partners. In addition to their obligate agaonid pollinators, a diverse community of non-pollinating fig wasps (NPFW) also uses the figs as a resource for the development of their broods. Some species of NPFW are gall makers and compete with the pollinators for the same pool of pistillate flowers. We experimentally demonstrated that the oviposition of the galling wasp Idarnes sp. group flavicollis at the beginning of anthesis does not interfere with stigma receptivity or the fig attractiveness of Ficus citrifolia . However, in situations of high Idarnes sp. infestation, the time window during which pollinators can enter the figs is shortened approximately by half. The enlargement of the Idarnes gall compresses the ostiole bracts, leading to an early closing of the fig ostiole, although the figs are still attractive. This negative effect on fig pollination seems to be more important in severely fragmented habitats where heliophilous fig tree species such as F. citrifolia are more abundant, favoring population of NPFWs, making over-infestation more frequent.