40
The Essex Naturalist
A new site for the RDB3 ant Myrmica bessarabica (=specioides) is Ironworks
Meadow, Maldon where a single worker was collected on 31st March 1998 by
the author and 3 more workers were collected on the 7th July 1998 by Adrian
Knowles.
A more detailed review of Essex ants appears elsewhere in this volume.
Spider wasps (Family Pompilidae)
A specimen of Anoplius concinnus collected in on the 16th August 1987 at
Hanningfield Reservoir by Roger Payne but only recently identified appears to
be a New County Record. The author has recently taken a further specimen at
the Rainham Marshes silt lagoons this year.
A record of Evagetes dubius shown for Essex at TQ67 in Edwards (1997) is
incorrect. The record originates from a specimen collected and provisionally
identified by Roger Payne from Broom Hill (West Tilbury). The determination
was reassessed but unfortunately the record had apparently already entered the
system. It should be deleted from the national atlas and the species remains
unrecorded in Essex.
Solitary wasps (Family Sphecidae)
Charles Watson collected a female Crossocerus cetratus at Chrishill on the 24th
August 1997, the third county record for this local sphecid wasp. Charles has
also taken one male of the Nationally Scarce Ectemnius sexcinctus at Takeley on
the 7th June 1997. This is a rare wasp in the county but with widely distributed
records.
Adrian Knowles also collected the Nationally Scarce (Na) Crossocerus
distinguendus from his garden in Colchester on the 7th June 1998, the first record
for north-east Essex. This species is very similar to C. elongatulus, a common
small sphecid wasp preying on aphids which is frequently present in gardens.
With new localities turning up in southern England it is difficult to assess
whether Crossocerus distinguendus is increasing its range or has previously been
overlooked.
Adrian Knowles has recorded two males of the RDB3 Diodontus insiduosus at
Danbury Common on the 16th June 1998. This species has been recorded in
Essex from Wanstead Flats (Hanson, 1992) but otherwise the only other county
records are by Penny Anderson Associates for Mill Wood Pit and the Chafford
Hundred area. Most records nationally seem to be from old heathland and acid
grassland commons.
This year the author has collected single females of the RDB3 Passaloecus
clypealis at Barling Pits, Barking PFA lagoons and Rainham Marshes silt lagoons.
This rare species has been recorded nesting within the empty 'cigar-galls' of the
chloropid fly Lipara lucens on Phragmites (Falk, 1991). In Essex the wasp has
been found in situations where Phragmites is growing in relatively dry situations