Having paid a number of visits to Thursley Common in the past couple of weeks to look for Brilliant Emeralds emerging, I have found a few areas where I managed to find a number of their exuviae. Despite not being able to actually find the dragonfly emerging on the days I was there, the film crew that I have been working with closely, made a visit to one of the areas a day later and managed to film a Brilliant Emerald emerging. What a result and worth the effort to help them hopefully film this quite rare sight. I decided on my return home that I would photograph the exuviae to show off some of the features needed to identify them. They are a nationally rare dragonfly and so to have their exuviae in my collection is very satisfying. The most obvious feature that I check for is the presence of a large dorsal spine on S9. This is very small or absent in the Downy Emerald. Two rows of black spots are also seen on the sides of the abdomen which the Downy lacks. The long spider type legs are also a feature of both Emeralds.
Side view
Top view showing dark spots running down the side of the abdomen
Brilliant stuff Marc, and to have a camera and know what you're talking about is essential. One up on me on both counts here Marc.
ReplyDeleteRespect....Pete.