The banded demoiselle (Calopteryx splendens) is among our largest equal-winged damselflies. From head to the end of the abdomen it measures about 45 mm, and the wingspan is about 6 cm. The abdomen and the thorax of the male are metallic blue, blending into metallic green. Its main characteristic is a wide dark blue band on the wings. Females are usually less conspicuous. Their body is entirely metallic green, and the wings are transparent with a slight greenish tint. The shimmering damselflies take pride in their beauty and are among the few damselfly species that court females before mating by displaying.
The banded demoiselle inhabits open and more sunlit waterways, as the larvae require more heat for development. Therefore it avoids mountainous regions, cold streams and rivers, and waterways in deep shade. It is less sensitive to the oxygen content in water and can also survive in somewhat more polluted waterways where oxygen is lower.
In warmer areas, adults already towards the end of April begin to flutter around the waterways and appear there until October; in cooler regions, the flight period is somewhat shorter.
