are mainly dependent on the water plants. The larvae need the stems and leaves, especially in areas with stronger currents to hold on. Hence it is extremely rare to find them in barren locations, flat expiring banks, or areas with a smooth stone floor. They also live in small natural lakes or ponds characteristic for limestones bedrock. They live in quieter areas between alluvial leaves or on exposed roots of the vegetation. They can be found on submerged plants such as waterweed (Elodea sp.), floods for water crowfoot (Ranunculus fluitans) or other plants, submerged from a few centimetres to several decimetres. Compared with the larvae of the banded demoiselle the larvae of the blue-wing demoiselle prefer quieter areas of the water, since slower flow causes a more effective absorption of oxygen under water. Only in very rare cases the larvae are present in stagnant water. The substrate of the river has only a very minor importance, because the larvae reside mainly in the vegetation. An important factor for the occurrence of blue-wing demoiselles is the oxygen in the water. The larvae is much more sensitive to oxygen deficiency than the larvae of the banded demoiselle, hence it needs a sufficient oxygen saturation of the water. Waters with high levels of sediment and sludge, which is consumed by bacterial decomposition of oxygen are, accordingly not as a habitat for the larvae. This sensitivity qualifies it in water chemistry as a bioindicator for the assessment of water quality. Thus they will be an indication of value in the saprobic assigned of 1.9, which represents a low to moderately polluted waters type (β-mesosaprob) and a water quality class from I to II does. Another key factor for the occurrence of the larvae of the blue-wing demoiselle is the temperature of the water. This species prefers unlike the banded demoiselle, mainly the cooler and shadier areas of the water. The optimal temperature is a summer average 13 to 18 °C. At temperatures above 22 °C were often injuries of larvae observed and also a reduced hatch ability of eggs. The main reason is the oxygen content under higher temperatures. Individual populations may get used to permanently higher temperatures. Adult habitat The habitat that the adults occupy, corresponds to the nearby larval habitat. Unlike the adults of the banded demoiselle you meet those of the beautiful demoiselle but also in forest clearings, but very rarely