The Black-tailed Skimmer is from the Family Libellulidae. It has a total length between 44 and 50 mm, a similar species is Orthetrum albistylum. The wings are clear and the pterostigma (cell in the outer wing) is black and the abdomen is broad and flattened in both sexes. Males have a bluish abdomen with yellow sides. Young males look similar to females but they change colour during maturation. Females have a bright yellow abdomen with longitudinal black bands. Young males and females can be told apart from their eyes, females’ eyes are darker. The abdomen turns darker during growth. The nymphs are aquatic, short, stocky and slightly flattened (1).
After mating the female will lay her eggs in a suitable place for the nymphs hatch. The nymphs moult several times as they grow. Mature nymphs crawl out of the water and after a while they emerge from the nymphal skin with unexpanded wings. After emerging wings expand as they dry (1). The flight season is from the end of April to the beginning of September, and is most abundant from June to August (2).
They are an active species. Males are often seen sheering fast and low above water or perching on open ground beside it (2), they can be very territorial (1).
They like large standing and slow-flowing waters, usually open and often with un-vegetated margins, e.g. lakes, sandpits and canals (2).
They can be found in all over Europe except the most northern parts, extending towards Kashmir and Mongolia. The Black-tailed Skimmer is one of the most common dragonfly species around Europe (2).
Description written by Aino Helakallio (2009)
(1) McGavin. G. (2004) Insects and Spiders, DK, London
(2) Dijkstra. K.D. (2006) Field Guide to the Dragonflies of Britain and Europe, British Wildlife Publishing, Dorset