Snake-flies, alderflies, lacewings and scorpion flies in Essex
records of S. lutaria and S. fuliginosa occurring together, but this is very rare. Small ponds are also
utilised. Emergent, or at least closely over-hanging, vegetation is a requirement for both egg laying
and for emergence of the adults. Trees or bushes are adjacent to all known Essex breeding sites.
Threats
Removal of emergent and marginal vegetation, scrub clearance on river banks and subtle changes in
water chemistry as a consequence agro-chemical run-off are all considered likely to limit the success
of a nationally common species that is already unexpectedly local in Essex.
Etymology
From the Latin lutum = mud, a reference to the silt-requirements of the larvae.
Sialis fuliginosa Pictet, 1836
National status: Local (Local) Predicted county status: Rare/Unknown
Distribution
The sole claim of this species to Essex status rests
in a female collected by Peter Harvey at Tilty on
22 June 1996, which I identified by examination
of the subgenital segment.
Habitat and ecology
All British breeding records relate to flowing
water, and in almost all cases the flow is fast,
although torrents appear unsuitable. There are.
however, some records from slow rivers, but
unlike S. lutaria, a flow of some sort seems to
be a requirement. The pH of the water seems to
matter little, and the only common factor seems
to be clear water with little or no silt.
Threats
It is desirable to establish whether or not the insect is present elsewhere in the county. If it is not, then
steps may need to be taken to safeguard its known site.
Etymology
From the Latin fuligin, the stem of fuligo = soot, a reference to the supposedly darker wings.
Order NEUROPTERA
The original Linnaean order 'Neuroptera' (Greek neuron = nerve and pteron = wing), included
many groups such as caddis flies (Trichoptera) and dragonflies (Odonata), which were subsequently
considered to be valid orders in their own right. During the twentieth century, Raphidioptera and
Megaloptera have also been separated from the Linnaean order, on the basis that they have biting,
rather than suctorial, mouth-parts. The present-day Neuroptera is the grouping that was formerly
regarded as sub-order Planipennia.
Six families of true lacewings arc found in the British Isles and, of these, five are found in Essex.
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Essex Naturalist (New Series) 17 (2000)