from twenty-four 10 km. squares in Essex since 1980. This expansion of O. cancellatum's
range in Essex is paralleled in surveys from elsewhere in Britain (for example, S.
Holland, 1983).
Sympetrum danae (Sulzer, 1776) Black Darter
This rather small darter dragonfly may be extinct as a breeding species in Essex, but
could easily have been overlooked. The mature males are more-or-less completely
black, and not easily confused with any other species. Females and immature males,
which are predominantly yellow could be confused with females of the two commoner
Sympetrum species. The best field-character for distinguishing the female of 5. danae is
its possession of a black triangular marking on the dorsal surface of the thorax. The
species has a patchy distribution throughout the British Isles, but is locally common
where its habitat, peat bogs and wet heathland, exists.
In a note to the Entomologist, dated September 16th, 1841. Henry Doubleday
speculated on the peculiar appearances and disappearances of three members of the
genus Sympetrum (H. Doubleday. 1841). These included 5. scotium (= danae) which, he
said 'has appeared in profusion', and at a spot previously hunted for years without any
being seen. According to Doubleday's later (1871) Epping list 5. danae was then
'common in certain years among the old gravel pits'. The Campion brothers did not see
the species in the Forest until 1906. when they found it at two separate sites there, one a
pond 'partly filled' with Horsetail. E. E. Syms (1929) also listed it, and according to
Pinniger (1933) it was 'always present in the Forest, though numbers fluctuate
considerably from year to year'. In fact. Pinniger's London Naturalist report for 1933
(Pinniger. 1934). mentioned that only one specimen of S. danae was seen that year.
Hammond's notes show that he did not see the species in the Forest until 1926, and
even then 'it never became common". After a long gap, there are further reports of the
species in Hammond's notebooks for 1944 and 1945. Pinniger. Syms and Ward (1950)
gave two separate reports of S. danae. One, from Syms, says it was 'in some numbers' at
one pond in the Forest. The other, from Ward, says that it was seen at one pond on the
fourth visit to the site hunting for it. It is not clear whether the two reports refer to the
same pond. Longfield (1949b) said it was known from the Forest 'before 1845 and has
been found there ever since, but is never common".
There are no Essex records for S. danae outside Epping Forest, where it seems to have
persisted in fluctuating (but generally very low) numbers and very few sites until the end
of the 1940s. It is not clear that the species was systematically searched for between 1950
and the 1970s. The more intensive surveying of the Forest which has taken place since
1979 produced no evidence of its continued existence, either in Epping Forest, or
elsewhere in Essex until a solitary male of the species was observed in Epping Forest by
A. McGeeney on the 16th August. 1987 (B.R.C.). It is as yet unclear whether this
individual was a 'wanderer' from a breeding site outside Essex, the result of an
unreported re-introduction, or whether, indeed, it is evidence of the continued presence
of a small breeding population in the Forest. Potentially suitable habitat for the species
continues to exist in the vicinity of Sunshine and Deershelter Plains.
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