Southern Hawker (Aeshna cyanea) | Species | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Male. Taken at Radley Lakes, Oxon., on August 22nd 2020. (1/250th sec at f13. Click image for larger version. © David Hastings) Male side view. Taken at Farmoor, Oxon., on August 17th 2019. (1/200th sec at f13. Click image for larger version. © David Hastings) Male, blue form. Taken at Whitecross Green Wood, Oxon, on August 12th 2011. (1/80th sec at f13. Click image for larger version. © David Hastings) Female. Taken at Farmoor, Oxon., on September 12th 2020. (1/500th sec at f13. Click image for larger version. © David Hastings) Female side view. Taken at Farmoor, Oxon., on September 12th 2020. (1/500th sec at f13. Click image for larger version. © David Hastings) Female, blue form. Taken at Fence Wood, Berks, on June 26th 2021. (1/400th sec at f11. Click image for larger version. © David Hastings) DescriptionWingspan: 86 - 106 mm; Body length: 67 - 76 mm A large, inquisitive dragonfly, usually seen individually. Unlike other hawkers, the spots on segments 8-10 are joined. The ante-humeral stripes are broad and strongly coloured. The costa is dark and there is an elongated triangular mark on S2. The male has a pronounced 'waist' between S3 and S4, which is missing in the female. The male is brightly marked on a dark background, usually apple green except for S8-10, which are pale blue. There is an all-blue form of the male. The female is brown with bright green markings, although there is a rare 'androchrone' form where the spots are blue instead of green. Immatures of both sexes are brown with pale yellow markings, and brown eyes. It is commonest south of a line between the Humber and Ribble estuaries, but has recently been spreading north into Scotland. It is absent from Ireland. Its breeding habitat is well-vegetated neutral or alkaline standing waters, sometimes shaded by trees. Unlilke other dragonflies it can tolerate small stangant ponds. Eggs are laid into rotting vegetation, often above the water line. They hatch the following spring and the larvae take two or three years to develop. Adults can be seen any time from May to November. The peak flight period is July to September. Adults mature well away from water, often around tree canopies in woodland glades. Mature males defend territories aggressively. Common in the south, local elsewhere. Sightings
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