62 The Essex Naturalist
Members of the genus Eumenes build delicate "pots" of clay, suspended from
plants and are referred to as the "potter wasps". Most species are supposed to
have only one generation per year, but those in genus Ancistrocerus may have
two if the spring comes early. Of the 22 British species, 16 (?17) are so far
recorded for Essex. Ecological notes are taken from Richards (1980).
Odynerus (Odynerus) melanocephalus (Gmelin in L.) - Notable A
Nests in flat soil and is not gregarious.
Listed for the Colchester area by Harwood (1884) without further detail. Scarce:
Colchester district (Nicholson 1928). Listed for North Essex by Falk (1991)
without details. We have recent records from Mill Wood Pit at Grays, a horse-
grazed grassland area with scrub to the east of Mill Wood Pit and from Broom
Hill (West Tilbury).
O. (Odynerus) spinipes L.
Nests in vertical sand faces.
Listed for the Colchester area by Harwood (1884) without further detail.
Shenfield and Colchester district (Nicholson 1928). In recent years we have
recorded this species from Mill Wood Pit, the nearby Grays Chalk Quarry,
Berwick Pond at Rainham and from Linford Sand Pit.
[O. (Spinicoxa) reniformis (Gmelin in L.)
Recorded in error. Published records in Harwood (1902) and Nicholson (1928)
relate to Odynerus (Spinicoxa) simillimus Morawitz.]
O. (Spinicoxa) simillimus Morawitz - RDB 1
Nests in either vertical or level ground; larval biology unknown but probably
provisioned with Lepidoptera or curculionid beetle larvae.
Very rare: Colchester (W H Harwood) and St Osyth (B S Harwood) (Nicholson
1928). According to Falk (1991), the following records, published as Odynerus
(Spinicoxa) reniformis (Gmelin in L.) also relate to this species: ". . . whilst
further out [of Colchester town] . . . both sexes of Odynerus reniformis, of which
we had previously taken a single specimen only" (Harwood 1902). Scarce:
Colchester district (Nicholson 1928). We know of no other Essex records.
Gymnomerus laevipes (Shuckard)
Nests in stems of bramble and elder, as well as herbs such as Arctium and
Carduus, provisioning its own larvae with those of Phytonomus (Coleoptera:
Curculionidae).
Rare: Billericay; Hale End - one, 2.vi.l918 in garden (Nicholson 1928). The
only recent record is from Dolphin Quarry, Purfleet in 1995.
Microdynerus exilis (H.-S.) - Notable B
Probably nests in small beetle holes in timber but also recorded nesting in the
ground. First recorded in Britain as recently as 19.37.
We have four Essex records available, from Mill Wood Pit, Grays in 1994 and
from Fobbing Hill in 1995, Broom Hill and Hall Hill (West Tilbury).