Lichen chemistry and selective grazing by the coleopteran Lasioderma serricorne

Part of the Lichenological Herbarium of the University of Trieste (TSB) was infested by Lasioderma serricorne, a polyphagus coleopteran. 1440 samples of 50 lichen species with different chemistry (Parmelia s.lat., Physcia s.lat.) were analyzed in order to assess whether the lichen diet of the insect was species- and especially lichen-chemistry-selective. Multivariate analysis indicates a significant negative correlation between the presence of some lichen substances and grazing phenomena. Atranorin, calcium oxalate, fumarprotocetraric acid, gyrophoric acid, lecanoric acid, skyrin, usnic acid and zeorin play an antiherbivorous role.