A revision of the Crane Fly genus Nephrotoma Meigen, 1803, in North America (Diptera, Tipulidae). Part I: The Dorsalis speciesgroup

In this study a taxonomic revision of the 20 nearctic species of the dorsalis-group is given. For each taxon the following data are presented: references, type material, material examined, diagnostic features, description, detailed drawings of male and female copulatory organs, biology and distribution with distribution maps. A separate key for males and females is presented. One new species is described (oosterbroeki), one is given new status (gnata) and one species is new for the Nearctic region (ramulifera). For the 20 taxa discussed, 37 names are known in literature; four of them are new synonymies, five other synonymies (proposed by Byers, in literis) are published for the first time. The taxonomic information is summarized in a checklist.