Abstract
Paracossulus thrips (Lepidoptera, Cossidae) is one of the locally distributed and endangered species. In Europe, it is also one of the few protected moth species, through Annexes II and IV of the Council Directive 92/43/EEC, Annex II of the Bern Convention. To date, little is known about the biology and ecology of this species. Our study was conducted in Transylvania, Romania. Romania hosts some of the strongest populations of the species in the European region. As part of the study, we conducted field observations, vegetation analyses, and genetic analyses. In our paper, we show the habitat types where we encounter P. thrips in Transylvania and confirm Phlomis tuberosa as a host plant. Furthermore, a piece of important information for habitat conservation is given. In this paper, we present the eggs and larvae of P. thrips, the first DNA barcoding sequences, and four new populations of P. thrips in Romania. Our study provides baseline knowledge about the biology and ecology of P. thrips, which is important for conservation and establishing management measures.