Review of the Lepidoptera of Essex for the year 2002
J.B., Geen, GR., Goodey, B., Goodey, M.A., Hall, J., Hanson, M.W., Harley, B., Harris, S., Harvey
N., Harvey, P., Heywood, M, Higgott, J., Huggins, C, Jeffries, T., King, D.S., Langmaid, J.R.,
Law, G, Long, M., Maisey, A.C., Mann, J., Marsh. R., Murphey, G, Newbery, L, Owen, D.,
Parmenter, P., Pateman, B., Perry, D., Plant, CW., Pyke, P., Rose, l.C, Shardlow, M., Sharp, K.,
Slater, G., Smart, D., Smith, P., Smith, P.J., Snowdon, G, Spence, J., Swaync, G, Waring, P., Wamcr,
D., Watkins, G. Wenlock, W.. Wilkinson, S.. Williams, J.
Essex dragonfly report for 2002
TED BENTON & JOHN DOBSON*
13 Priory Street, Colchester CO1 2PY
*148 Main Road, Danbury, Chelmsford CM3 4DT
The current (2001 onwards) survey of the county's dragonflies has been well-supported and we now
have some 4,500 records on file. Already coverage is comparable with that reported in Benton
(1988), and first impressions are that all species then present continue to maintain their former
presence in the county. Species such as Calopteryx virgo and Cordulia aenea, which seem always to
have had a very restricted distribution in Essex, have held their own, but show no evidence of
expansion.
Three localised species, Lestes dryas, Brachytron pratense, and Platycnemis pennipes, have all
been reported from new sites during the current survey. It is difficult to be sure how far this represents
genuine expansion, and how far it is a result of increased recording activity in the areas concerned.
However, in the case of'B. pratense, it seems most likely that the species is strengthening its presence
in the county, with reports from coastal and estuarine marshes (its former strongholds) as well as
inland sites. It now has a more extensive distribution along the Chelmer/Blackwater, continues to be
well-established on the Cornmill Stream/Old River Lea in the west, and has an apparently isolated
breeding site at Markshall, near Coggeshall. This species may well be under-recorded, and we would
particularly welcome reports of new sightings. In appearance it is quite similar to the more widespread
'hawkers' Aeshna cyanea and A. mixta (particularly the latter), but is smaller, and flies much earlier
- from mid-May through June.
Platycnemis pennipes is another species which, as we reported last year (Benton & Dobson 2002),
also seems to have expanded its range in the county since the 1980s. Previously recorded from the
Chelmer/Blackwater Navigation, Sandon Brook, Cornmill Stream/Old River Lea and the Roding, it
is now known also to be well-established along the Stour, the higher reaches of the Blackwater, the
Rivers Wid, Chelmer and Ter. Lestes dryas continues to hold its own in the coastal marshes, and in
suitable ditches, pools and fleets along the Thames and Crouch estuaries. Particularly late adults of
this species were observed during a visit to Foulness on 24/08/02.
Further records were obtained during the season of the two recent colonists of the county: Erythromma
viridulum and Libellula fulva. The former remains widespread in the county, and we have received
reports of sightings in several more localities. On 25/07/02, the authors observed a small number of
males on a small patch of water-lily leaves on the lake at Thorpe Hall, Thorpe-le-Soken. Elsewhere,
Rigid Hornwort Ceratophyllum demersum reached the water surface, and here were more male E.
60
Essex Naturalist (New Series) 19 (2003)