Flower flies (Diptera: Syrphidae) in Pampean agroecosystems: a study case

Agroecosystems produce profound alterations on the structure and functioning of the original environment, mainly due to the reduction of biodiversity. Flower flies (Diptera: Syrphidae) are potentially useful organisms for the diverse ecosystem services they provide. We studied syrphids collected in a Pampean agroecosystem to assess richness, abundance, host plants, and the ecosystem services they could offer. Flower flies were represented by three subfamilies, eight tribes, 17 genera, and 26 species/morphospecies. Adults of these flies visited flowers of 44 species of wild and/or cultivated plants and exhibited a generalist interaction pattern. Larvae of the most abundant species were predators (mainly soft-bodied Hemiptera) and/or decomposers/aquatic filters. Only one species was pollinivorous. Our results, together with the scarce published bibliography, suggest that the syrphid communities of the highly modified Pampean region are composed of a few very abundant species and many rare or low representative species.