Interaction data between ants, aphids and wasps in riparian habitats in Southern California

These data document networks of interactions among aphid-tending ants, ant-tended aphids, and aphid-attacking parasitoid wasps differ between 12 spatially paired riparian study sites with and without the introduced Argentine ant (Linepithema humile) in Southern California. To resolve challenges in species identification, we used DNA barcoding to identify aphids and screen for parasitoid wasps (developing inside their aphid hosts) from 170 aphid aggregations sampled on arroyo willow (Salix lasiolepis).