Order Coleoptera: Introduction

Abstract

Coleoptera represents one of the largest orders of aquatic invertebrates with about 18,000 species in 37 families, 30 of them occurring in the Neotropical region. These families include predominantly aquatic, not predominantly aquatic, and shore beetles, belonging to the suborders Adephaga, Myxophaga, and Polyphaga. Aquatic beetles live in almost every kind of freshwater environment, such as rivers, streams, lakes, ponds, pools, ditches, wetlands, phytotelmata, and ground waters. Many species are benthic, although there are also neuston dwellers, species living exclusively on aquatic plants and others that ?walk? on the underside of the surface film. Several species are able to swim and dive and many others stay submerged for most of their life. Aquatic beetles exhibit a variety of feeding habits. Most species are carnivorous, either predaceous or scavengers, feeding on zooplankton, other invertebrates and even small vertebrates. Several species are omnivorous, and many others are herbivorous, feeding mainly on algae, soft mud, decaying plant material, organic matter or detritus. Water beetles are diverse both ecologically and in terms of life-history, and are functionally important in most inland waters, being involved in a range of ecosystem processes such as nutrient cycling and processing. They have proven to be very useful as biological indicators and suitable for developing management criteria and selecting priority areas for aquatic conservation.