A second update to the checklist of Finnish long-legged flies (Diptera: Dolichopodidae), with a re-evaluation of the status of Hydrophorus callosoma Frey, 1915

Eighteen species of long-legged flies (Dolichopodidae) are reported as new to Finland. A further species, Microphorella praecox (Loew), is confirmed as a Finnish species. The status of Hydrophorus callosoma Frey, 1915 is re-evaluated and a lectotype is designated for the species. H. albosignatus Ringdahl, 1919 is found to be a junior synonym of H. callosoma (syn. n.). Characters for identifying both sexes of H. callosoma and H. altivagus Aldrich are presented and illustrated with high-quality photographs.