Biology of two European Tenthredo species (Hymenoptera, Tenthredinidae) feeding on Gentiana

Abstract

Very few sawflies using Gentianaceae as larval host plants have been recorded. We identified larvae collected in Austria on Gentiana asclepiadea L. as Tenthredo atra Linnaeus, 1758 and T. propinqua Klug, 1817. If its current taxonomic circumscription as a single species is accepted, T. atra is a highly polyphagous species, whereas T. propinqua may be more specialised: Gentiana asclepiadea is its first recorded host. We sequenced plant DNA from the head of one T. propinqua larva, which confirmed that it had been feeding on this plant. This is the first recorded use of G. asclepiadea by sawfly larvae. Larvae are illustrated, and identification characters are described.