The common darter is a dragonfly of the family 'Libellulidae' native to Eurasia. It is one of the most common dragonflies in Europe, occurring in a wide variety of water bodies, though with a preference for breeding in still water such as ponds and lakes. In the south of its range adults are on the wing all year round.

Females have light yellow thorax and abdomen. Males turn red as they mature. Females darken with age, becoming a dark chocolate brown, and sometimes develop a blue colouration to the bottom of the abdomen. The wings also develop a brown tinge with age. In all cases the legs have a cream or yellow stripe on a black background - this is a diagnostic feature of this species.

This small dragonfly is seen in a wide variety of habitats, including lakes, ponds, canals and slow-flowing rivers. They are ambush predators, waiting on a prominent perch - such as a leaf or the top of a gate, until prey fly past, whereupon they will fly after it. They are territorial on breeding waters, often attempting to chase much bigger dragonflies away such as southern hawkers.

More Info: en.wikipedia.org