Invertebrate survey at Gunpowder Park, the former Royal Ordnance Site in the Lee Valley
the margins of ponds and ditches. It is a species of open sunny places, where adults can normally be
seen sitting on herbage or the sunlit foliage of nearby trees (Stubbs & Drake 2001).
Syrphidae Cheilosia velutina Notable/N, Essex Red Data species
The species was netted in Areas B and C. The larval host may mine the stems of Cirsium palustre,
and adults are often found at the flowers of white umbels such as Daucus carota. It has been found
to be relatively frequent in suitable habitat in the East Thames Corridor, but the species remains
poorly known with very few confirmed records, mainly on the eastern side of Britain.
Syrphidae Heringia (Neocnemedon) vitripennis Local, Essex Red Data species
The species was found in Area B. This hoverfly is widely distributed, at least within England, but
infrequently found. It is rare in Essex. The larvae are mainly predacious on adelgid aphids and have
been found attacking the woolly aphid on firs and coccids on Lombardy Poplar. Woodland rides
and margins provide typical habitat (Stubbs & Falk 2002).
Syrphidae Volucella inanis Notable/N, Essex Red Data species, Regionally Important
The species was seen in numbers in Arca D. The larvae of this large hoverfly arc ectoparasites of
social wasp larvae, and have been found in association with Vespula germanica and Vespa crabro.
They are found in open areas in woodland and scrub and, most frequently, in suburban areas, in
parks and gardens where adults are usually seen visiting flowers, especially white umbels and
Buddleja (Ball & Morris 2000). In some years it is locally abundant in the outer suburbs of London
and the surrounding countryside. Although reports indicate that it is expanding its range to the
north, it also appears to have contracted eastwards with very few records from central-southern and
south-western counties (Stubbs & Falk 2002).
Syrphidae Volucella zonaria Notable/N, Essex Red Data species, Regionally Important
The species was seen in numbers in Area D. This, our largest and most spectacular hoverfly, seems
to be almost entirely anthropogenic in Britain. Its larvae are scavengers and predators in the nests
of social wasps (including the hornet Vespa crabro), where they probably feed on larvae and pupae.
It is usually seen visiting flowers in suburban areas where it occurs in parks and gardens. Many
recent records come from civic amenity plantings around car-parks and urban roads (Ball & Morris
2000). Until about 1940 it was regarded as a rare vagrant to the south coast of England, then,
during the 1940s, it began to become established in the London area and is now quite frequent,
especially in the outer suburbs and in northern Kent. Current evidence shows this species is expanding
its range into Suffolk and Norfolk, and north and west from London into Hertfordshire and along
the Thames valley (Stubbs & Falk 2002).
Tachinidae Cistogaster globosa RDB1, Essex Red Data species/NCR
This parasitic fly was swept off Carrot Daucus carota flowers in area B. C. globosa was allocated
RDB1 status by Shirt (1987) and Falk (1991). The most recent review (Falk & Pont in preparation)
has provisionally accorded the species RDB2 status. It is known from a few localities in Southern
England and is a distinctive species unlikely to be overlooked and probably genuinely rare. The species
parasitises hctcropteran bugs, in Europe the shieldbug Aelia (Pentatomidae), mostly A. acuminata
(Belshaw 1993), the only species of the genus found in Britain. This host species was found in areas
B and C, but not found elsewhere at the site. The egg is laid on the dorsal surface of the host's
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