First records of three species of long–legged flies (Diptera: Dolichopodidae) of the subfamily Medeterinae from Slovakia are presented. Systenus pallipes (von Roser, 1840) and Systenus leucurus Loew, 1859 emerged from rearing units with sediment from a water–filled tree hole of elm (Ulmus sp.), and Systenus scholtzii (Loew, 1850) from rearing units with similar sediments from birch (Betula sp.). The relevance of this approach i.e. the rearing process of immature stages from tree holes in laboratory conditions is briefly discussed.