Mayflies (Ephemeroptera) of the great plains. I: Nebraska

A total of 13 families, 39 genera, and 81 species of Ephemeroptera are repo rted from the state of Nebraska, including the first published state record s for two families, 13 genera, and 38 species. Also provided are 335 new co unty records for 65 of the species. Mayflies are now known from 60 of the 9 3 Nebraska counties and from all drainage areas represented in the state. M ost species of the Nebraska fauna are relatively common in North America. N otable exceptions include Apobaetis lakota to McCafferty, Brachycercus edmu ndsi Soldan, B. nasutus Soldan, Cercobrachys serpentis Soldan, Leptophlebia gravastella (Eaton), and Paraleptophlebia gregalis (Eaton). Much of the ma yfly fauna is psammophilous, being typical of sand-bottomed streams, which are predominate throughout much of the state. The generally mixed North Ame rican geographic affinities of the Nebraska fauna are tabulated, and severa l species significantly demonstrate their eastern, western, or northern ran ge limits in this north-central plains state.