32 The Essex Naturalist
Males of the Nationally Scarce (Nb) Chrysis helleni were taken at
Alphamstone Pits in June and July 1996 by Colin Plant and myself and another
male was taken at Glemsford Pits. Both these sites are in the interesting area
between Colchester and Sudbury in north Essex. As yet the species, a parasitoid
of the locally common sphecid wasp Tachysphex pompiliformis, has not been
found in South Essex, where the host is common at a number of sites.
One female of the Nationally Scarce (Nb) Cleptes semiauratus was taken at
West Thurrock PFA lagoons in September 1996. This chrysid wasp is a
parasitoid of the common currant-sawfly Nematus ribesii, a garden pest of
redcurrant and gooseberry. Falk (1991) states that it was formerly widespread
and locally frequent especially in gardens, but is now scarce everywhere and
seems to have declined considerably. The reasons for this are far from clear but
the use of pesticides and climatic factors are two possibilities.
Family Tiphiidae
One male and female of the Nationally Scarce (Notable B) wasp Tiphia minuta
were taken in traps at Alsa Sand Pit in June/July 1996 by Colin Plant,
apparently the first record for North Essex. The larvae are probably parasitoids
of dung beetle larvae.
Velvet ants (Family Mutillidae)
One female of the Nationally Scarce (Notable B) Small Velvet Ant
Smicromyrne rufipes was taken at Middlewick Ranges in Colchester on 21st
August 1996 by Jerry Bowdrey the first recent record for North Essex.
Family Sapygidae
One male of the Nationally Scarce (Notable B) Club-horned Sapyga Sapyga
clavicornis was taken at dead wood at the side of a spring-fed marsh at Bran End
on 1st June 1997. The species is a parasite of bees in the genera Chelostoma and
Osmia. This is the first recent record of the species away from the Thurrock area
in South Essex.
Ants (Family Formicidae)
Two rare ants were recorded at Goshams Farm between Tilbury and East Tilbury
this year. Colin Plant took a single worker of the Nationally Scarce (Notable B)
Ponera coarctata and there were numerous workers of the Nationally Rare
(RDB3) Myrmica specioides in areas with sparsely vegetated thermophilic
conditions.
Since the ant previously recorded as Stenamma westwoodi was split into two
separate species, most records in Britain have been referable to Stenamma debilis.
This has also been the situation in Essex where all records have been for
Stenamma deblis except for a single queen taken at Broom Hill, West Tilbury and
determined by the late John Felton. It is therefore of considerable interest to
report two males and two queens collected by D.A.J. Hunford at Thundersley in
October 1990 and a worker possibly of this species collected by R.G. Payne at a
copse in Southend.