Our knowledge of the past distribution of this species in Essex is somewhat confused,
owing to the difficulties of reliably distinguishing it from C. puella. H. Doubleday (1871)
reported it as 'not uncommon about the ponds by the side of the new road through the
Forest', but it did not appear on the later lists for the Forest provided by the Campions or
by Hammond. However, Syms (1929) listed it, as did Pinniger (1933): 'occurs rarely
throughout the Forest'. The species was not mentioned in Pinniger's subsequent annual
reports in the London Naturalist (1934-8), but in recent personal correspondence
Pinniger tells me it was present till the 1940s. It was reported from Wanstead Park by F.
A. Walker (1897), but his record was not referred to by either W. J. Lucas (1900b), who
certainly knew of it, or W. H. Harwood (1903). This suggests some scepticism about the
identification of the species, and it is possible this also accounts for Cynthia Longfield's
comment that the species had 'not been known anywhere in the county' since
Doubleday's list until it was seen at Foulness in 1943. I have no further details of this
1943 discovery, but it may be that the species spread out from Foulness into nearby
suitable habitat, since it was discovered in flooded pits at Hawkwell in 1976 by E. T.
Levy (S.C.M.). There is also a Suffolk record from the River Stour and associated
meadows in the vicinity of Hundon and Clare, where it was seen by M. Chinery in
1970.
During the survey period, thorough searches of the Stour and other possible sites
have produced only one reliable record of the species in our county. This was for the Old
River Lee on 10th August, 1983. B. Eversham saw 'small numbers' of adults and 'several
larval exuviae' (per. comm.), so that it seems there was a breeding colony there in 1983.
Unfortunately subsequent searches for the species at this site have so far failed to
confirm its continued presence. It does, however, occur at a number of north Kent
localities, so that re-colonisation of south-east Essex should not be ruled out.
Enallagma cyathigerum (Charpentier, 1840) Common blue Damselfly
One of the commonest and most widely distributed species of Odonata in Essex, and
in the rest of Britain. The males are best picked out from other common 'blue and black'
species (and, in particular, from Coenagrion puella, which they most closely resemble) by
the absence of black markings on segments 8 and 9, which are thus clear blue. Less
evident in the field, but a useful back-up feature is the distinctive stalked black blotch on
segment 2 of the abdomen. Females occur commonly in both green and blue forms, and
are best distinguished by the 'arrow' shaped black markings on the abdominal
segments, and by a ventral spine on segment 8 (not possessed by Coenagrion spp.).
This species appears to be tolerant of a wide range of habitats but is particularly
successful at colonising newly created ornamental lakes and ponds, including garden
ponds, reservoirs and gravel pits. Unlike C. puella they appear to require areas of open
water between water margins, or fringes of emergent vegetation. Often, E. cyathigerum is
the most abundant species at newly created sites, and frequently appears in huge
numbers. Males, especially, fly out low over open water, often well away from water
margins, sometimes settling on floating debris. Water-lily leaves, etc. whilst females are
more characteristically found among marginal vegetation or rank grasses often at some
distance from the breeding site. Pairs in tandem are commonly observed flying low over
open water. Where a fringe of emergent vegetation (such as Reed-mace) is present,
males are strongly territorial, adopting favourite 'perches' a few inches above the water
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