The Essex Naturalist
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Essex. The species is a parasitoid of small wood-nesting sphecid wasps such as
Passaloecus and Pemphredon (Falk 1991). Another ruby-tailed wasp new to the
county is Hedychridium roseum taken at Tiptree Heath by Adrian Knowles on
the 14th July 1998. The species is a parasitoid of the Astata boops, a sphecid
wasp which is very rare in Essex. Recent work (Archer & Allen, in Edwards,
1998) suggests that both the Hedychridium and the Astata should have their
status revised (to Nationally Scarce Nb) and the distribution map in Edwards
(op. cit.) shows that Hedychridium roseum is mainly confined to the heathlands
of Dorset, Hampshire, West Sussex and Surrey.
A third ruby-tailed wasp taken by the author this year at Barking PFA
lagoons is yet another new county record. The Nationally Scarce (Na) Cleptes
nitidulus, together with the ant-mimic jumping spider Synageles venator at the
Barking PFA lagoons represent quite remarkable and important discoveries.
Cleptes nitidulus is a parasitoid of sawfly cocoons with post-1970 records confined
to eight widely scattered localities (Falk, 1991). Morgan (1984) states that
Cleptes nitidulus is often found in stable dune localities with Salix spp. and
Synageles venator is also normally associated with dune systems. The area of old
(PFA) lagoons at Barking lie over former grazing marsh there are some quite
remarkable dune-like formations resulting from weathered and compacted PFA
as well as remnant grazing marsh dykes, marshy areas of Phragmites and sedge,
banks of sparsely vegetated PFA and areas of scrub and ruderal flower-rich
vegetation.
Velvet ants (Family Mutillidae)
One male of the Nationally Scarce (Nb) Small Velvet Ant Smicromyme rufipes
was taken at Colne Point on the 20th June 1998 by Adrian Knowles. The
Nationally Scarce (Nb) Large Velvet Ant Mutilla europaea was recorded by
Roger Payne at Two Tree Island on the 1st September 1997 and a single male
was seen by the author on Cerastium flowers behind the sea wall at Barling on
the 17th June 1998.
Ants (Family Formicidae)
Essex holds important populations of the Nationally Scarce (Na) Lasius
brunneus. Adrian Knowles has collected the species during 1998 at Warley Park
Golf club on the 11th May and the author has recorded the ant several new
localities this year. At Chestnut Wood, Hanningfield on the 9th May 1998
workers were running along cut pine logs lining a new ride; at Bundish Spring
on the 4th July 1998 workers were found on the bark of an old oak trunk at the
edge of a field in a hedge; at Hoddens Wood near Brentwood on the 3rd July
1998 workers were running on the surface of a very large old rotten beech trunk
and several workers were seen on the 5th July 1998 on the trunk of a very old
apple tree in the garden of a public house in Blackmore!