This is a mid season dragonfly, appearing from mid / late May and can be seen on the wing through to mid / late August.
This is one of the four blue bodied dragonflies found in the United Kingdom. It could be easily confused with the Scarse Chaser; however they rarely appear at the same site together and the Scarse Chaser has black tips to its wings. The Keeled Skimmer is somewhat smaller and lacks the black tail segments, whilst the much sturdier Broad Bodied Chaser has a wider abdomen.
The Black Tailed Skimmer is generally a stillwater species and is usually one of the first dragonflies to colonise newly dug gravel pits. It's also found on canals and slow flowing rivers.
The immature male and the female are similar in appearance in that they are of a yellow / straw colour with two irregular stripes running along their abdomen. Close examination of their anal appendages will determine the sex, the females being widely spaced apart.
The female dulls as it matures while the males abdomen turns a fine shade of blue with black segments on its tip. Both sexes have clear wings and the costa's are yellow.