Male. Taken at Standlake Common, Oxon., on July 14th 2024. (© David Hastings)
(1/640th sec at f11. Click image for larger version)
Male. Taken at Chimney Meadows, Oxon., on June 2nd 2022. (© David Hastings)
(1/800th sec at f11. Click image for larger version)
Teneral female (f. rufescens). Taken at Whelford Pools, Gloucs, on June 16th 2023. (© David Hastings)
(1/640th sec at f11. Click image for larger version)
Teneral female (f. violacaea). Taken at Whelford Pools, Gloucs, on May 18th 2013. (© David Hastings)
(1/100th sec at f11. Click image for larger version)
Teneral female (f. typica). Taken at Whitecross Green Wood, Oxon., on June 12th 2023. (© David Hastings)
(1/640th sec at f13. Click image for larger version)
Mating wheel. Taken at Whitecross Green Wood, Oxon., on June 7th 2021. (© David Hastings)
(1/500th sec at f11. Click image for larger version)

Description

Wingspan: 28 - 42 mm; Body length: 30 - 34 mm

The Blue-tailed Damselfly is one of the commonest British species. Mature males always have a blue spot on S8, blue ante-humeral stripes on the thorax and blue eyes. The immature male has a greenish thorax. Females vary with at least 5 different colour forms. The thoracic markings and the tail spot are violet in the immature form "violacea", but salmon pink thorax and blue spot in the form "rufescens". When mature the female may be blue (like the male) in the form "typica", olive green thorax and brown spot in the form "infuscans", or pale brown thorax and brown spot in the form "infuscans-obseleta".

This species can be found almost anywhere in the British Isles, with the exception of the Scottish Highlands.

It can be found in a wide range of habitats, including brackish and polluted waters, although it avoids acidic and fast flowing waters.

Eggs are laid into submerged plants and debris, without males in attendance. Adults emerge after one year on the south and two in the north. The main flight period is May to August.

Males are terrotorial. Most adults remain close to water, often congregating in large numbers in bankside vegetation. Although not a strong flier, adults readily disperse to new locations.

A common and widespread species.

Earliest UK sighting: 25th April ; Latest UK sighting: 12th September

Sightings