36 The Essex Naturalist The Nationally Rare (RDB3) Passaloecus clypealis seems to be very rare in Essex with only two males and a female recorded from Ferry Fields Tilbury in 1994 and 1995 (Harvey 6k Plant, 1996) and an older record from Benfleet given in Falk, 1991 and Richards, 1980. Ferry Fields is soon to be lost to industrial development and it is therefore fortunate that numerous males and females were taken in pan traps at West Thurrock PFA lagoons in August 1996 near an area of rather dry Phragmites marsh. The Nationally Scarce (Notable B) 'cuckoo' wasp Nysson trimaculatus has turned up at new sites across the county, suggesting that although scarce it may be quite widespread. There are new 1996 records by Colin Plant, Ray Ruffell and myself for Barking Levels and West Thurrock PFA lagoons in the East Thames Corridor and Alphamstone, Alsa Sand Pit, and Coneyfield Wood in North Essex. Nysson dimidiatus, a Nationally Scarce cleptoparasite of the sphecid wasp Gorytes tumidus has been recorded in the county for the first time tor nearly a century. In July and August 1996 it was taken hy Colin Plant and myself at Barking Levels and then at West Thurrock PFA lagoons in South Essex and at Alphamstone in North Essex with its host. One male was then taken at Goshams Farm in June 1996 again with its host. It seems to have been a good two years for Nysson species. A single male of the Nationally Scarce (Notable A) Alysson lunicornis was taken at Alphamstone in August 1996. Adults resemble pompilids (spider- hunting wasps) in behaviour and are very difficult to capture. They are said to be associated with patches of bare or sparsely vegetated clayey soil, especially where deep cracks provide entrances for their nests (Falk 1991). The two other recent Essex records have been in exactly this kind of situation in the bare cracked clay of an old inland sea wall bank at Fobbing Marshes and on the bare land-slipped clay at The Cliff at Burnham-on-Crouch (Harvey 6k Plant, 1996). On 19th July 1996 Roger Payne collected the small sphecid wasp Stigmus pendulus from Priory Park in Prittlewell Southend (Payne, 1997) and then Adrian Knowles took the species along the Gryme's Dyke at Colchester on three occasions in July 1997. Individuals were seen exploring old beetle holes in bark damaged patches on mature oak (pers. comm.). This record greatly extends the known British range for the species, which may be spreading. Falk (1991) lists only a single male collected at Smarden, E. Kent in August 1986 and two females taken from Wanstead Flats and Leyton Flats in South Essex collected by Mark Hanson. However Colin Plant has also collected the species at The City of London Cemetery, Wanstead and the species has turned up regularly in malaise trap material from Buckingham Palace Gardens during a co-operative venture being carried out by the LNHS and the British Museum (Natural History) to record the entire flora and fauna of the garden. Gorytes bicinctus (Notable B) seems to be widespread in the East Thames Corridor. Further records have come to light since the publication of the provisional county list (Harvey 6k Plant, 1996) for Shoebury Old Ranges (R.G.