Diversity of the Bibionomorpha and Tipulomorpha (Diptera) from dead ash and aspen wood in the forests of Lithuania

The aim of this study was to investigate the biodiversity of nematoceran flies associated with dead wood in a forest ecosystem. Although wood is a primary habitat for a vast amount of Diptera species, no effort has previously been made to study saproxylic flies in Lithuania. During this research, emergence traps were used on aspen (Populus tremula) and ash (Fraxinus excelsior) trees in Dūkštų Ąžuolynas forest and Būda Botanical-Zoological Reserve during the period 2014–2019. In total, 672 individuals of the Bibionomorpha and Tipulomorpha collected from fallen tree trunks were identified to species. Seventy-four species represented nine families, with the Sciaridae, Anisopodidae and Mycetophilidae being most abundant. The Sciaridae family has barely studied in Lithuania and its diversity is still poorly known. During the research 23 nematoceran species, of which 19 belonging to the Sciaridae family, are first reported from Lithuania. Key words: nematoceran, saproxylic species, emergence traps.