A rapid bioassessment tool for the evaluation of the water quality of transitional waters

► Chironomids are reliable indicators of water and habitat quality. ► In the present study we develop a water quality index (EQAT) based on the chironomid pupal exuviae assemblages. ► The index was significantly correlated with trophic variables and the TRIX index. ► This is cost-effective tool for assessing water quality, something that was lacking in transitional waters.