Offspring sex ratio shifts of the solitary parasitoid wasp, Trichopria drosophilae (Hymenoptera: Diapriidae), under local mate competition

Authors

• Jing Li
• Yu Wang
• Cheng-Jie Zhu
• Min Zhang
• Hao-Yuan Hu

DOI:

https://doi.org/10.33338/ef.71221

Abstract

Localmate competition (LMC) models predict a female-biased offspring sex ratio when a single foundress oviposits alone in a patch and an increasing proportion of sons with increasing foundress number. We tested whether the solitary pupal parasitoid, Trichopria drosophilae (Hymenoptera: Diapriidae), adjusted offspring sex ratio with foundress number when parasitizing Drosophila melanogaster pupae. Mean number of female offspring was higher than that of males, with a male proportion of 26 ± 16% when only one foundress oviposited. However, male proportion reached 58 ± 26%, 48 ± 22%, and 51 ± 19% in three-, five and seven-foundress cohorts. That the male proportion of offspring increased with foundress number is consistent with LMC models.