Snake-flies, alderflies, lacewings and scorpion flies in Essex
it is almost certainly confined. The late Geoff
Pyman found examples at Blakes Wood, Little
Baddow and at Little Baddow Heath during 1993
and more recently Geoffrey Wilkinson spotted
an example on the River Can at Chignal St. James,
on 23 July 1999 (Wilkinson 1999); on a return
trip a few days later he secured a specimen for
me to confirm the identity. These are the only
Essex records known. In Britain as a whole, it is
principally found in the western half of Britain,
but is also tolerably widespread in the southern
counties from Kent to Dorset.
Habitat and ecology
The Giant Lacewing is normally associated with
fast flowing streams where its amphibious larvae are predators of the splash zone, amongst mosses.
Broad-leaved woodland features prominently at almost all British sites.
Threats
Apart from a single record from Norfolk, the Essex population is the only one between the Thames
and the Humber in eastern England. The microhabitat of a mossy splash zone alongside a relatively
fast-flowing stream containing water of low organic content, suspended solids and Biological Oxygen
Deficiency, all in association with broad-leaved woodland, is a rare feature in Essex and is susceptible
to pollution, disturbance and other factors. For this reason, the Giant Lacewing is regarded as a
Vulnerable species in Essex. There is a relatively urgent need for a thorough survey of potential new
sites and for management plans to be prepared for sites at which it is present.
Etymology
A combination of the Latin fulvus = tawny/yellowish-brown with the Greek kephalikos = head;
literally "tawny head".
Family SISYRIDAE — the sponge flies
The Sponge Flies arc small, brown lacewings that live, in the larval stage as internal parasites in
freshwater sponges. Existing records all relate to hosts in the Spongillidae — for which reason the
lacewings are referred to as Spongilla flies in the older literature. There are three British species, all
in the same genus, but only one of these is found (or indeed expected) in Essex.
Sisyra fuscata (Fabricius, 1793)
National status: Local (Common)
Predicted county status: Common/-
Distribution
Widespread but local. The distribution map probably more faithfully represents my own light-trapping
sites than the real distribution of the species; the western bias is not likely to be real. It is very likely
to be found wherever there are freshwater sponges, including in ponds, lakes, streams and rivers, but
adults come readily to light of all types and so are often found outside their expected breeding area-
Habitat and ecology
Beyond knowledge that freshwater sponges are required as hosts little is known of the biology of
this species. Elsewhere in Britain, larvae of Sisyra fuscula have been found in the sponges Spongilla
lacustris and Ephydatia fluviatilis; this represents the sum of all knowledge of host sponges of the
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