[Sex ratio adjustment of a non-pollinating fig wasp species on Ficus semicordata in Xishuangbanna].

Through controlling the number of ovipositing foundresses inside a fig,and combining with the observation of ovipositing behavior and mating behavior,this paper studied the sex ratio of Apocryptophagus sp.,a species of non-pollinating fig wasps hosted on Ficus semicordata in Xishuangbanna. The results showed that female Apocryptophagus sp. started to visit the fig on the 3rd day after pollinator Ceratosolen gravelyi oviposited. Apocryptaphagus sp. oviposited on the outside of the fig,and the ovipositing lasted for 2 days. Male Apocryptophagus sp. emerged at the same time with pollinators. The males opened a small hole on the wall of gall where the females developed,and mated with the females. Mated females emerged from their development fig,and left for a new receptive fig. The sex ratio of Apocryptaphagus sp. was in agreement with local mate competition theory,i.e.,it was female-biased. Meanwhile,the total number of offspring increased with increasing foundress number. In contrast,the average number of offspring per foundress decreased. At individual level,when a female laid eggs inside a fig,the sex ratio of offspring correlated negatively with the number of offspring.