These photos supplement pages 67-73 of the Guide to Aquatic Invertebrates of the Upper Midwest. Information on the biology of Coenagrionidae can be found on page 70. The gills of Coenagrionidae can sometimes be missing, so use the other characters and general body shape for identification. The main difference between Coenagrionidae and Lestidae is the width of the labium. Coenagrionidae have a wide labium (below). Lestidae have a narrow labium; click to compare with Lestidae.