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Lifetime reproductive success in female insects is often egg- or time-limited. For instance in pro-ovigenic species, when oviposition sites are abundant, females may quickly become devoid of eggs. Conversely, in the absence of suitable oviposition sites, females may die before laying all of their eggs. In pollinating fig wasps (Hymenoptera: Agaonidae), each species has an obligate mutualism with its host fig tree species [Ficus spp. (Moraceae)]. These pro-ovigenic wasps oviposit in individual ovaries within the inflorescences of monoecious Ficus (syconia, or ‘figs’), which contain many flowers. Each female flower can thus become a seed or be converted into a wasp gall. The mystery is that the wasps never oviposit in all fig ovaries, even when a fig contains enough wasp females with enough eggs to do so. The failure of all wasps to translate all of their eggs into offspring clearly contributes to mutualism persistence, but the underlying causal mechanisms are unclear. We found in an undescribed Brazilian Pegoscapus wasp population that the lifetime reproductive success of lone foundresses was relatively unaffected by constraints on oviposition. The number of offspring produced by lone foundresses experimentally introduced into receptive figs was generally lower than the numbers of eggs carried, despite the fact that the wasps were able to lay all or most of their eggs. Because we excluded any effects of intraspecific competitors and parasitic non-pollinating wasps, our data suggest that some pollinators produce few offspring because some of their eggs or larvae are unviable or are victims of plant defences

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A new genus of a Neotropical gall inducing tetrastichine eulophid on Araceae is described and confirmed using Ultraconserved Elements (UCE) phylogenomic data. Arastichus Gates, Hanson, Jansen-González & Zhang, gen. nov., includes two new species and one species transferred from Aprostocetus Westwood: A. capipunctata Gates, Hanson, Jansen-González & Zhang, sp. nov., A. gallicola (Ferrière), comb. nov., and A. gibernau, Gates, Hanson, Jansen-González & Zhang, sp. nov.

The association between ontogenetic processes in plants and phytophagous insects is not traditionally considered in studies of insect-plant interactions. Angiosperm seeds impose important constraints on seed predators; the structural complexity of seeds and the progressive accumulation of resources throughout their development limit the time windows when resources can be retrieved by the predator. Some holometabolous insects deposit their eggs inside immature seeds, with the immature stages of both insect and plant cohabiting in a space with limited but potential resources. We studied the larval development of Megastigmus transvaalensis (Hussey, 1956) (Chalcidoidea: Megastigmidae) and Bephratelloides pomorum (F., 1804) (Chalcidoidea: Eurytomidae) and the seed development of their respective hosts, Schinus terebinthifolia (Raddi, 1820) (Anacardiaceae) and Annona crassiflora (Mart., 1841) (Annonaceae). Our results show that both M. transvaalensis and B. pomorum oviposit in immature fruits, whose protective tissues surrounding the seeds are softer. The first larval instar interferes little with the development of the seed, allowing both seed and plant embryo to continue growing. When the infested seed reaches the size of a mature, non-infested seed, the larva grows rapidly and consumes most of it. M. transvaalensis induces minor modifications in the endosperm cells, while B. pomorum does not induce any visual modifications. The strategy of allowing seed/plant embryo to continue growing shows similarities to the endoparasitic koinobiont strategy followed by some chalcid parasitoids, which keep their host alive while feeding upon it. Future studies should be expanded to other chalcid seed predators in order to understand the evolution of convergent patterns among seed-feeding insects and its evolution in relation to parasitoid strategies inside the group