Abstract

Insects are virtually ignored in ecological studies of littoral marine environments in Chile. Although they are known to feed on decaying organic matter, recent data suggest a more active role in community processes, but the available information is extremely scarce. With the aim to determine insect taxa occurring at the littoral zone of Concepción, Chile (ca. 36°40? S), and their potential ecological importance in that system, we conducted an exploratory study in four localities: Caleta Tumbes, Cocholgüe, mouth (saline) of the Bío-Bío river, and Punta de Parra. At each locality, we assessed the diversity of insects in the high, mid and low intertidal zones, recording the habitat or type of substratum to which they were associated. We found 24 insect species, both native and introduced, distributed in four orders and 18 families, including midges, rover beetles, and crane flies. Some of the species were considered casual records. Diversity was higher in the mid intertidal zone, particularly in the rocky intertidal fringe where macroalgae are more abundant. We also detected recurrent associations between insects and the most common intertidal algal species (in situ or washed ashore, live or decaying), apparently used as habitat or food, suggesting a key role in the recycling and exchange of nutrients between intertidal and subtidal systems. Some terrestrial predatory insects seemed to forage consistently on patches of insects associated to decaying algae, generating lateral interaction chains with the intertidal system. We discuss the community membership of insects and the research perspectives arising from this study.