Venomics of antlions and aphid lions
Neuropteran larvae are fierce predators that use venom to attack and feed on arthropod prey. Antlions (Myrmeleontidae) are adapted to dry, sandy habitats, where they use pitfall traps and venom to catch and subdue large arthropods. In contrast, aphid lions – the larvae of green lacewings (Chrysopidae) – primarily hunt for smaller prey such as aphids. The venom systems of both families are poorly understood. We therefore investigated the tissue origin, composition and ecological role of venom in the European antlion Euroleon nostras and green lacewing Chrysoperla carnea. We found that antlion venom has potent insecticidal activity, indicating its use for the rapid immobilization of large prey, whereas aphid lion venom is nontoxic, reflecting its use to feed on smaller, non-defensive prey. Histological and proteotranscriptomic analysis revealed that antlion venom is produced in three distinct glands that secrete different proteins, indicating the functional compartmentalization of venom compounds. The antlion venom system also contains no bacteria, providing strong evidence that all venom compounds are of insect origin rather than the products of bacterial symbionts as previously suggested. Our study provides a detailed analysis of neuropteran venom systems and new insights into venom biochemistry and functions that may underpin the adaptation of antlions to their unique ecological niche.