from yesterday, the Dragonfly emergence...and the "exuvia"...
Dragonflies undergo incomplete metamorphosis; unlike other winged insects, such as butterflies, dragonflies do not have a pupal stage and transition straight from a larva to an adult. This transition, the final larval moult, takes place out of water. This metamorphosis is triggered by day length and temperature, and is synchronised in some species, such as Emperor Dragonfly, which is why I find so many at once at my pond, where yesterday's and todays pics were taken.
Larvae climb up emergent vegetation, although some may walk several metres over dry land before finding somewhere suitable to emerge. After finding a secure support, they redistribute their body fluids, pushing the thorax, head, legs and wings out of the larval skin. There is then a pause of about 30 minutes to allow their legs to harden enough for the next stage, when the abdomen is withdrawn. The wings, and then the abdomen, are expanded and start to harden. This process leaves behind a cast skin, called an exuvia.
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