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Status and distribution
Cordulegaster boltonii (Donovan) Golden-ringed dragonfly
Description C. boltonil is a large hawker dragonfly with a very striking appearance, having
a black and yellow body and green eyes. The abdomen of males widens
towards the posterior end giving it a club-shape similar to the much smaller
Gomphus vulgatissimus, but the pattern of yellow markings is quite different. C.
boltonii owes its vernacular name to the series of paired yellow.markings on
the dorsal surface of the abdomen which extend to the sides and give the
appearance of rings. Female coloration is similar to the male.
Habitat C. boltonii breeds in boggy runnels and moderate- to fast-flowing rivulets,
streams and rivers with a silt, gravel or stony bed, usually in western and
upland areas but also on lowland heaths.
Breeding biology Males patrol long lengths of stream flying very low, usually less than 50 cm
from the surface and much lower than Aeshna juncea which can occupy similar
habitat. They are very aggressive but do not defend particular territories.
After a lengthy copulation away from water, the female, unaccompanied by the
male, hovers by the edge of the stream and thrusts her abdomen down in a
stabbing motion pushing her eggs into sediment with her long ovipositor. In
fast-flowing stony streams, quiet backwaters are selected where silt has been
deposited. The larvae usually take more than two years to develop, and have
been known to take four or five years. They live partially concealed in the silt
with just their eyes and the end of their abdomen protruding and they prey on
passing organisms. In boggy runnels, the larvae may also be found in peaty
detritus along with larvae of Orthetrum coerulescens.
Flight periods C. boltonii is on the wing from early June to early September. It may be seen
with Calopteryx virgo and Pyrrhosoma nymphula on streams, and with the
latter species and 0. coerulescens near bogs.
In Britain, C. boltonii is widespread in western and upland districts from
Cornwall to the extreme north of Scotland, and on the southern lowland heaths
of Dorset, the New Forest, Surrey/Hampshire border and Ashdown Forest in
Sussex. It is absent from much of central and eastern England. In Ireland,
despite an abundance of apparently suitable habitat, C. boltonii has not been
recorded authentically. Sélys-Longchamps (1846) listed C. boltonii as Irish
from 'Northern Lakes', on the basis of information gained from the eminent
Irish entomologist, Haliday, during the former's visit to Ireland in 1845. A
specimen, apparently taken by Haliday in Ireland, is in the National Museum,
Dublin (King & Halbert 1910). On 24 August 1986, an individual of the genus
Cordulegasterwas observed closely, while settled, by R Thorpe, at Firkeel in
Co Cork, at the mouth of Bantry Bay. As this would represent beyond doubt an
addition to the Irish List, absolute proof of specific identity is necessary, and,
as a result, the record has not been mapped in this Atlas.
European and world C. boltonli is found widely in Europe from Portugal to southern Scandinavia
distribution and east to Russia. It is rare or absent in lowland areas bordering the North
Sea, and absent from the eastern Mediterranean. There are several European
subspecies.
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