A pyramidal trap with combined bait is described and illustrated. The trap inserted above sapping stump of European walnut (Juglans regia) in a site in Central Bohemia near Uhlířské Janovice in 2010 yielded a rich spectrum of flies (Diptera). Records of 24 species most interesting from the faunistic, biological and nature conservancy point of view are given with comments upon their distribution and biology but a number of other captured species are also mentioned. Besides species developing in or attracted as adults to sap runs [e.g. Syrphidae: Ceriana conopsoides (Linnaeus, 1758), Aulacigastridae: three Aulacigaster spp., various Drosophilidae], other important components were formed by saproxylic [Xylomyidae: Solva marginata (Meigen, 1820), some Stratiomyidae, many Lonchaeidae, Milichiidae: Milichia ludens (Wahlberg, 1847), some Muscidae], mycophagous (some Asteiidae, Sphaeroceridae, Drosophilidae), necrophagous (some Sepsidae, Acartophtalmidae, Milichiidae, Sphaeroceridae) and saprophagous (some Sepsidae, Carnidae, Milichiidae, Sphaeroceridae) species, both latter attracted to meat-bait used in the trap. Aulacigaster falcata Papp, 1998 is the first record from Bohemia.
