Four magnificent dragonflies adorn the new issue of self-adhesive definitives: “Beautiful Demoiselle” (face value: CHF 0.85), “Blue Emperor” (face value: CHF 1.00), “Large Red Damselfly” (face value: CHF 1.80) and “Banded Demoiselle” (value: CHF 2.60). Nature photographer Xaver Roser caught these insects on camera.
All the depicted dragonflies are indigenous to the Ruggeller Riet nature reserve. The biocenoses of the fens found there also include numerous endangered plant and animal species which fortunately do not include the four dragonflies shown. Dragonflies count among the most important bioindicators. They say a lot about the quality of the waters and wetlands. Their four wings, each of which operate independently and combined weigh at most one centigramme, are unique. Large dragonflies can fly at a speed of more than forty kilometres per hour without backwind, accelerate extremely quickly, stop abruptly in full flight or suddenly change direction. In contrast, the exceptional manoeuvrability of small dragonflies in tight spaces is impressive to watch.