A revision of the Palearctic species of the shore-fly genus Discomyza Meigen (Diptera: Ephydridae)

The four Palearctic species of the shore-fly genus Discomyza Meigen are revised, including the description of an undescribed species. The undescribed species, D. baechlii, is found at higher elevations mainly in Austria and Switzerland (type locality: Graubunden: Ausserferrera-Cresta (1300-1670 m; 46 degrees 28'N, 9 degrees 31'E). Three species, D. baechlii, D. incurva, and D. maritima, form a monophyletic species group; the fourth species, D. maculipennis, has only been found in Japan in the Palearctic region and is undoubtedly an introduction from the Oriental region. Lectotypes are designated for: Discomyza amabilis Kertesz, Discomyza pelagica Frauenfeld and Psilopa incurva Fallen.