Are aquatic and semiaquatic true bugs (Hemiptera: Nepomorpha; Gerromorpha) distinct aquatic communities? A case study in homogeneous habitats

We investigated the environmental factors influencing Nepomorpha and Gerromorpha in lentic, highly vegetated habitats from the Danube Delta. We collected 7032 individuals from 12 species from 23 habitats over 6 months. Separate multivariate analyses were conducted on the entire species dataset and separately on aquatic and semiaquatic species. Statistical analyses showed that aquatic and semiaquatic true bugs are influenced by different sets of environmental variables. Hydromorphological factors are most important in influencing communities of aquatic species, whereas aquatic plant species most strongly influence communities of semiaquatic species. Thus, including closely related taxa in a wider, more general analysis might lead to biased and/or distorted conclusions, and detailed analysis of the different related taxa is recommended to establish whether they do not represent distinct communities.