Now that the sun is shining again, we bring you the most amazing series of images taken by one of our enthusiastic supporters of The Sandstone Ridge.
We previously covered a sighting of a broad bodied chaser and an article entitled 'Such is Nature' CLICK HERE.
We now bring you a series of photographs which shows the emergence of a 4-spotted chaser from its final moult, taking it from its larval stage, as a nymph, to the adult dragonfly. This took place recently at a garden pond in Tilston. The entire process from emerging from the final moult to take-off was approximately 2.5 hours.
The life cycle of many insects is fascinating, involving very different looking creatures at different
stages of the life cycle. We are probably all familiar with many of these stages, but it is rare to see the
development process from one stage to another actually occur.
Nymphs are voracious aquatic predators that hide within vegetation or burrow into the sediment to
ambush unwary prey. From eggs, they will grow for about two years, during which time they will
undergo several moults. The 4-spotted chaser nymph is squat and robust, with short legs, as can be
seen in the photos. When they are fully developed, they leave the water, in this case by climbing a
grass stem early in the morning, to shed and emerge from this final skin as winged adults. This
process is often synchronised between individual nymphs, so that one may find several newly-
appeared and empty nymph cases attached to the stems and leaves of aquatic plants.
This newly-emerged adult dragonfly, or teneral, is soft-bodied and pale in colouration, with the wings
clearly compressed and folded.
Over the next two hours or so, the sequence of photographs shows the body extending and the wings expanding as blood is pumped through, and finally hardening in the sunshine. Clearly at this stage the dragonfly cannot fly and is vulnerable to predation. However, with the wings fully unfurled and hardened, and with its 4 wing spots now appearing, this chaser dragonfly finally took flight.
Our thanks to Nick Holmes for these superb images.
Click on each image to enlarge.