Marietta - the Odes
Image from iNaturalist
Washington County, Ohio, (Marietta is the County seat) has 62 species (https://www.inaturalist.org/observations?captive=any&place_id=1697&project_id=9978&verifiable=any&view=species)
98 species are located in roughly a 40 mile radius from Marietta (https://www.inaturalist.org/observations?lat=39.47697354283054&lng=-81.45734027803965&place_id=any&radius=84.13721559886031&subview=table&taxon_id=47792&view=species&iconic_taxa=Insecta).
Narrowing the search to June, there are 73 species (https://www.inaturalist.org/observations?lat=39.47697354283054&lng=-81.45734027803965&month=6&place_id=any&radius=84.13721559886031&subview=table&taxon_id=47792&view=species&iconic_taxa=Insecta).
The meeting will be in late June; at this time some of my favorite species which should be found include Phanogomphis exilis, Arigomphus villosipes, Libellula incesta, Dromogomphus spinosus, Leucorrhinia intacta, Progompus obscurus, Hetaerina americana, Celithemis fasciata, Anax longipes, Macromia illinoiensis, Hagenius brevistylus, Gomphurus fraternus, Epiaeschna heros, Phanogomphus lividus, Ladona deplanata, Nehalennia irene, Cordulegaster obliqua, Didymops transvera, Gomphurus vastus, Nehalennia gracilis, Rhioaeschna mutata, and Stylogomphus albistylus. These are listed from most to least abundant in the listing; species in bold can be expected to be seen on one of the main field trip locations, the Little Muskingum River (and adjacent ponds/wetlands).