First records about oxygen consumption by Chironomus sancticaroli (Diptera: Chironomidae): an analysis using microsensors

The Chironomidae family is one of the most abundant insect groups in freshwater environments. This group is one of the main organisms of benthic fauna due to sediment and vegetation colonization, with high morphological and physiological adaptations. The importance of chironomid responses to changes in the aquatic environment could allow them to be used to monitor streams, lakes, and ponds. Despite the great ecological importance and the high number of studies, little is known about oxygen consumption by insect larvae in aquatic systems. This fact may be related to the difficulty of measuring these limnological variables in small organisms like Chironomidae larvae, and the need for refined equipment. A microsensor is a small electrochemical electrode used in laboratories for chemical species detection. Its small dimension offers advantages, such as the small sample volume required. In this study we evaluated for the first time the dissolved oxygen consumption in the Chironomus sancticaroli Strixino et Strixino, 1981 larvae using microsensors. The results of the experiments showed that there was a high oxygen consumption by C. sancticaroli larvae under laboratory conditions. The technology of microsensors applied in the study of the aquatic invertebrates seems to be important for obtaining detailed information on the biology of these organisms.