Fast life in cold water: Diamesa incallida (Chironomidae)

Development times of Diamesa incallida and its numbers of generations per vear were studied using in situ reanngs in conjunction with continuous collection of egg masses from the field The evidence suggested that the crenophilous D incallida laid eggs throughout the year and produced eight to ten generations per year, depending on water temperature (76°C to 80°C) This is the first proof for a muitivoltine Diamesinae as well as for continuous egg laying behaviour by a non–troprcal chironomid The comparatively large mature larvae (96 mm, 710 μ.g a f d weight) and the numerous generations per year indicate that D incallida is a highly productive component of crenal communities The importance of rearing chironomids over a sufficient number of generations is emphasized as a basis for the reliable interpretation of field data