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Coenagrion scitulum (Rambur) Dainty damselfly
Description Like other Coenagrion species, the males of C. scitulurn are blue with black
markmgs. The black mark on segment 2 of the abdomen is 'typically' a thickstalked
U-shape, but this is subject to such variation that it is probably
incorrect to refer to it as typical. This mark may be much reduced in size to
the extent that the individual can superficially resemble a small Enallagma
cyathigerum. Females are dull blue-green with black abdominal markings. A
pointer in the direction of a captured individual being something special is the
shape of the pterostigma, which is elongated in both sexes, being nearly twice
as long as broad and unlike all other coenagrionids likely to be encountered in
Britain, in which the pterostigma is roughly square.
Breeding biology Territorial behaviour has not been recorded. Oviposition takes place in
tandem with the male, with the male sloping forward, unlike the near-vertical
posture which is usual for other Coenagrion males. The eggs are inserted into
the tissues of aquatic plants. The larvae probably take one year to develop.
Flight period The recorded flight period of C. scitulum in Britain is from late May to the end
ofJuly.
Status, distribution It has only ever been known from Essex and was first discovered near Benfleet
and history on 21 July 1946 by E B Pinniger whilst leading a London Natural History
Society meeting, in the company of Cynthia Longfeld, to look for Lestes dryas
(Pinniger 1947). The ditches in this area were stagnant, and some brackish,
and overgrown with spiked water-milfoil and sea club-rush. First a male was
found, of a species unknown to either of them, and then two females a short
distance away. These were taken by Longteld and subsequently identified as
C. scitulum. The area was searched thoroughly the following year, and C 0
Hammond found a pair on 22 May at the known locality. Later, the main
breeding site was found to be a few miles to the east, near Hadleigh, at a pond
containing common water-crowfoot. In 1951, RE Gardner counted over 250
individuals at this site. C. scitulum was last seen on 22 June 1952, again by
Gardner. Early in 1953, much of the east coast of England was disastrously
flooded, including Canvey Island and the marshes at Hadleigh. Despite many
searches, C. scitulum was never found again. A fuller account of this species'
residence in Essex is given by Benton (1988). C. scitulum has been recorded
from Guernsey and Jersey in the Channel Islands. It almost certainly bred on
Guernsey, having been recorded at Chouet on 29 June, 2 July and 28 July 1956
by J Cowley Ten males and two females, taken during the latter two visits, are
in the Natural History Museum, London. Belle (1980) could find no trace of the
species on Guernsey in 1978, and believed it to be extinct. Le Quesne found
three individuals on Jersey in 1940 and 1941, at St Peter's Reservoir and
Grands Vaux (Le Quesne 1951), but proof of breeding was not established.
European and world C. scitulum is a Mediterranean species with isolated populations in several
distribution countries of central Europe.
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