Distribution of odonates (dragonflies and damselflies) in the Indiana Dunes National Lakeshore and nearby lands

From 1993 to 1997, 60 species of Anisoptera (dragonflies) and Zygoptera (damselflies) were found in Lake and Porter Counties, Indiana, including Indiana Dunes National Lakeshore, in contrast to 34 species that were recorded historically from this region. We added 17 new species to Lake County's odonate records and 39 new species to the 5 previously recorded in Porter County. Several regionally rare species were collected: Aeshna clepsydra, Enallagma cyathigerum, and Leucorrhina frigida. Nine species listed in the historical records were missing from our collections: Hetaerina americana, Calopteryx aequabilis, Nehalennia irene, Arigomphus furcifer, Argia fumipennis violacea, Gomphus spicatus, Epitheca princeps, Libellula exusta, and Sympetrum semicinctum. These nine species have either declined in the area or they may be found in other habitats after further study. Because few odonate surveys were conducted in northwest Indiana in the past, a poor baseline exists for comparisons of temporal trends in odonate diversity.