THE RESPONSE OF LARVAL GROWTH RATE TO TEMPERATURE IN THREE SPECIES OF COENAGRIONID DRAGONFLIES WITH SOME COMMENTS ON<i>LESTES DISJUNCTUS</i>(ODONATA: COENAGRIONIDAE, LESTIDAE)

Abstract

Abstract Larval growth rate has the same temperature coefficient in three species of coenagrionids, but Argia vivida and Amphiagrion abbreviatum, which frequently live in geothermally heated water, grow fastest at 29.0–30.0°C compared with 23.4°C for Coenagrion resolutum, which lives in cooler water. Survival below 15°C in the laboratory was much better in C. resolutum. These characteristics are reflected in the distributions of the three species, C. resolutum ranging much further north in North America than the other two species, but not penetrating as far south. By contrast, the temperature coefficient for Lestes disjunctus is higher than that of the coenagrionids, and this is related to a different life history. In the coenagrionids, one or more winters are spent in the larval stage. In L. disjunctus, winter is spent in the egg stage, and larval growth must be completed quickly.