New records of sawflies (Hymenoptera, Symphyta) feeding on leaves of birch (Betula sp.) in Slovakia

New data on the distribution of 11 Symphyta species phyllophagous on birch trees ( Betula L.) are presented. Dineura virididorsata (Retzius, 1783), Heterarthrus nemoratus (Fallén, 1808), Nematinus caledonicus (Cameron, 1882), Pamphilius varius (Audinet-Serville, 1823), and Pristiphora alpestris (Konow, 1903) are reported from Slovakia for the first time. The little-known Allantus cingillum (Klug, 1814), Euura ampla (Konow, 1895), E. leionota (Benson, 1933), Profenusa thomsoni (Konow, 1886), Trichiosoma lucorum (Linnaeus, 1758), and T. vitellina (Linnaeus, 1761) were found in Slovakia, either after many decades or for the second time.