said that an abundance of brown-tail larvae is bound to affect adversely other species with which it
competes.
An insect which owed its inclusion on the British list to a single occurrence in Essex until one
appeared in Kent in 1983, is a geometer of the same genus of moths with distinctly angled wings as the
tawny-barred angle (Semiothisa liturata) to which it bears some resemblance. It is S. signaria called
the dusky peacock in Skinner (1984). The insect appeared at light in an Essex Naturalists' Trust
nature reserve on Danbury Ridge in June 1970. The species has a wide distribution on the Continent
where its larvae are a serious pest on both pine and spruce. Neither of these conifer groups is
represented in the reserve but Norway spruce is plentiful in adjoining plantations. As the moth was
taken in such close proximity to one of its host trees, it was thought that it might have established itself
in the area. But it has not been seen again and we must assume that it was either a wind-blown
wanderer itself or had flown from a small local colony, founded by a migrant female, which has
quickly died out
No less remarkable was the recent discovery that two noctuids taken at Bradwell-on-Sea in 1963
and 1964 respectively were examples of the sandhill rustic (Luperina nickerlii), a rare species
previously thought to be restricted to small colonies on our western seaboard. The moths apparently
belong to the nominate subspecies, L. n. nickerlii which had not previously been recorded in Britain.
A search was made for its breeding ground and once its habits had been learnt (see systematic list) it
was found to be abundant on the drier parts of salt-marshes from Harwich to Canvey Island.
Another newly discovered species which occurs freely in Essex is the lesser common rustic
(Mesapamea secalella). It can be separated from the common rustic (M. secalis) with certainty only
by examination of the genitalia. Research in 1984 showed that it occurs in many parts of the county
though less plentifully than the common rustic.
The above are but a few examples of the many interesting larger moth species that occur, or have
occurred, in Essex. The picture is an ever-changing one as new species take up residence while others
are lost or become rare. The study of the Essex macrolepidoptera and indeed of the microlepidoptera,
so expertly presented in an earlier publication (no. 6) in this series, will provide the student with a
lifetime of learning, interest and pleasure.
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