Problematic fossils from the Upper Cretaceous of western Bulgaria might be the first record of Mesozoic insects in the country

Recent work at the Upper Cretaceous vertebrate locality near the town of Tran, western Bulgaria, brought to light a diverse assemblage of plant mesofossils and other microfossils of uncertain systematic affinities. Here we briefly report on 18 problematic specimens that share a striking morphological similarity to the Late Cretaceous Knoblochia cretacea, an ichnotaxon thought to be an insect egg. This material appears to represent the first record of Mesozoic insects from Bulgaria.