Keeled Skimmer (Orthetrum coerulescens)
Species
Keeled Skimmer (Orthetrum coerulescens). Male. Taken at Dry Sandford Pit, Oxon., on June 15th 2018. Approx 3x lifesize.
Male. Taken at Dry Sandford Pit, Oxon., on June 15th 2018.
(1/320th sec at f14. Approx 2x lifesize. Click image for larger version. © David Hastings)
Keeled Skimmer (Orthetrum coerulescens). Male side view. Taken at Persec, France on June 28th 2010. Approx 3.75x lifesize.
Male side view. Taken at Persec, France on June 28th 2010.
(1/250th sec at f11. Approx 2.25x lifesize. Click image for larger version. © David Hastings)
Keeled Skimmer (Orthetrum coerulescens). Female. Taken at Dry Sandford Pit, Oxon., on June 11th 2018. Approx 3x lifesize.
Female. Taken at Dry Sandford Pit, Oxon., on June 11th 2018.
(1/320th sec at f13. Approx 2x lifesize. Click image for larger version. © David Hastings)
Keeled Skimmer (Orthetrum coerulescens). Female side view. Taken at Dry Sandford Pit, Oxon., on July 12th 2018. Approx 3x lifesize.
Female side view. Taken at Dry Sandford Pit, Oxon., on July 12th 2018.
(1/160th sec at f14. Approx 2x lifesize. Click image for larger version. © David Hastings)
Keeled Skimmers (Orthetrum coerulescens). Mating wheel. Taken at Crockford Stream, Hants, on July 15th 2011. Approx 2.5x lifesize.
Mating wheel. Taken at Crockford Stream, Hants, on July 15th 2011.
(1/800th sec at f11. Approx 1.5x lifesize. Click image for larger version. © David Hastings)

Description

Wing span: 56 - 66 mm; Body length: 36 - 45 mm

The Keeled Skimmer is a rather small dragonfly with a slim abdomen, which has a pronounced dorsal keel. The wings have a straw yellow costa and yellow or brown pterostigma. At rest, the wings are often held well forward. The thorax has pale yellow ante-humeral stripes which fade with age in the male. Males have blue-grey eyes and a brown face. Females have a pale, yellowish-brown abdomen with a medial black line.

It is scarce and local in the British Isles, being found mainly in southern and south-west England, western Wales, western Scotland and western Ireland.

This species is closely associated with acidic wet heathland sites.

Eggs are laid on the wing. The small hairy larvae live in bottom debris and take at least two years to mature. The main flight period is June to August.

Males have relatively small territories which they defend from low perches. Flights are fast and erratic, with frequent brief spells of hovering. Mating occurs on the ground and can last for 30 minutes or more. Immatures can often be found well away from suitable habitat.

A scarce and local species. It can be abundant at good sites.

Sightings

12-Jul-2018 : Parsonage Moor, Oxon (15m,4f)
12-Jul-2018 : Dry Sandford Pit, Oxon (3m,3f)
12-Jul-2018 : Cothill Fen, Oxon (4m,1f)
26-Jun-2018 : Corney Fell, Cumbria (1f)
25-Jun-2018 : Eskdale, Cumbria (2f)
24-Jun-2018 : Irton Fell, Cumbria (2m,1f)
24-Jun-2018 : Wasdale, Cumbria (13m,1f)
23-Jun-2018 : Meathop Moss, Cumbria (1f)
15-Jun-2018 : Dry Sandford Pit, Oxon (3m,2f)
11-Jun-2018 : Dry Sandford Pit, Oxon (1 ten)

06-Aug-2017 : Dry Sandford Pit, Oxon (1m)
14-Jun-2017 : Dry Sandford Pit, Oxon (1f)
03-Jun-2017 : Dry Sandford Pit, Oxon (4ten)

07-Aug-2016 : Cothill Fen, Oxon (10m,1f)
09-Jul-2016 : Dry Sandford Pit, Oxon (1f)
28-Jun-2016 : Dry Sandford Pit, Oxon (2)
02-Jun-2016 : New Copse Inclosure, Hants (1)

08-Aug-2015 : Dry Sandford Pit, Oxon (1)
12-Jul-2015 : Parsonage Moor, Oxon (1f)
12-Jul-2015 : Cothill Fen, Oxon (1m,1f)
02-Jul-2015 : Dry Sandford Pit, Oxon (1m,3f)
06-Jun-2015 : Dry Sandford Pit, Oxon (3 ten)

24-Aug-2014 : Parsonage Moor, Oxon (1f)
24-Aug-2014 : Cothill Fen, Oxon (3m,1f)
28-Jun-2014 : Dry Sandford Pit, Oxon (1)
25-Jun-2014 : Rupite Hot Springs, Bulgaria
24-Jun-2014 : nr Novo Hodzhovo, Bulgaria
18-Jun-2014 : nr Mirkovo, Bulgaria
14-Jun-2014 : Dry Sandford Pit, Oxon (1m)
08-Jun-2014 : Parsonage Moor, Oxon (1 ten)