Abstract:

In the fig-fig wasp reciprocal mutualism, understanding mechanisms of coexistence between pollinating wasps and non-pollinating wasps is an important and relevant topic. Niche partitioning has widely been considered as the most important mechanism in the coexistence of pollinating and non-pollinating wasps. In this study, we experimentally examined the diet of five species of non-pollinators and the relationship among fig wasps in Ficus racemosain Xishuangbanna, southern China, from Dec. 2006 to Jun. 2007. Platyneura testacea and P. mayri are gall-makers, but oviposit sequentially, utilizing different female flowers at different developmental stages; Apocryptasp., A. westwoodi and P. agraensis are parasitoids of P. testacea, P. mayri and Ceratosolen fusciceps respectively, presenting species-specific relationships with the hosted species. Species correlation coefficients differed greatly among seasons and conditions, suggesting that the use of correlation analysis to deduce or identify relationships between species in previous studies may be of limited value. Pollinators were the dominant species at our study sites. In these conditions, non-pollinating wasps exist at relatively low population density, and therefore may have a weak impact on the stability of the mutualism, potentially enabling the non-pollinating wasps coexist with the mutualism between figs and fig wasps.

Key words: mutualism, fig, non-pollinator fig wasps, diet, niche separation, Xishuangbanna