Lentic beetles of the Missouri Prairie Region: Habitat and regional associations, with keys to the hydradephaga

Approximately 12,000 specimens of adult aquatic Coleoptera representing 9 families and over 100 species were collected from 105 anthropogenic ponds within the Missouri Prairie Region in August-September 1998, March-April 1999, and June 1999. Within ponds, habitats comprising monospecific stands of aquatic macrophytes, including emergent vegetation, were identified, from which the coleopteran fauna was collected. Taxonomic keys and annotated lists for 55 species of Hydradephaga collected from ponds, including likely pond inhabitants, are presented. Within the Hydradephaga, 20 species were new Missouri state records. Inter-pond and inter-habitat analyses were performed to elucidate aquatic coleopteran community structure and habitat associations. Species richness of aquatic Coleoptera differed significantly among habitats in August-September 1998 and June 1999, but not in March-April 1999. Generally, emergent vegetation supported beetle communities with higher richness than did submerged vegetation. Results from analyses of large-scale factors indicated that beetle species richness in most ecoregionalization schemes did not differ among subregions.