Unfortunately it is necessary to examine the spiders with a microscope to determine which of the two
species has been found. Atea triguttatus is a beautiful Araneid spider found on trees and bushes. It
has an almost triangular abdomen and pink brown colour that seems to glow.
The larger Araneid Gibbaranea gibbosa has two characteristic humps on the front of its abdomen
and is usually brown with greenish sides. Cyclosa conica is another curious Araneid with silvery
markings and an abdomen extended into a single tubercle. It makes an orb web that usually has a
stabilimentum. a conspicuous band of silk above and below the centre of the web. The spider spins
the remains of its meals into this band so that when it sits between the two halves it is almost impossible
to see. There are various ideas about the function of the stabilimentum (Shear, 1986). Silk represents
a considerable commitment of protein to a spider which it can ill afford to have go to waste and many
spiders will ingest and recycle their web at the end of its useful life. The stabilimentum may warn
birds of the web's presence so that they will not fly into the web and destroy it. It has also been
suggested that the stabilimentum is a strengthening structure or provides camouflage to the spider.
Some species of linyphiid spider are commonly found in foliage for example Hypomma cornutum,
Entelecara acuminata and Gongylidium rufipes. The males of Hypomma and Entelecara both have
elevated heads and in Hypomma it is also bilobed. Although a very widespread species the Hypomma
does not seem to have yet been recorded from the Forest. The male of the very rare Trematocephalus
cristatus (Fig. 2-2) has an extraordinary lobe that comes forward to meet the front of the head, leaving
a hole right the way through! This species was found new to Essex in 1989 on oak in woodland near
Colliers Hatch. This is not far from the northern parts of the Forest and the species could well occur
within its area.
A completely different habitat is the woodland leaf litter layer. Even in the height of summer when
the surface layer of dead leaves may be dry, down in the litter the humidity will be maintained. In the
middle of winter when the surface is frozen, underneath the temperature may be considerably warmer
and the invertebrates still active. Many linyphiid species are found in this habitat and indeed many
mature and are sexually active through the late autumn, winter and early spring period. Spiders that
are found in the foliage in early summer are also found as immatures overwintering in the leaf litter
layer and amongst the dead leaves that accumulate against the base of the trees and in hollows or
ditches.
In spring and early summer the wolf spider Pardosa lugubris can be seen running about in
considerable numbers on the leaf litter, especially in the more open areas at the edge of clearings. The
male is a very handsome spider, a characteristic white band of hairs down the middle of its carapace
contrasting with the black hairs over the rest of its body. The female is much more subdued with its
brown colours matching the background of dead leaves.
Cicurina cicur is a very local agelenid spider that has been found under rotten logs in the Forest.
Elsewhere in Essex I have taken the species in grassland as well as woodland habitats. At the moment
its distribution in the county looks interesting with records restricted to the south-west region but this
may turn out to be due to under-recording particularly since the species is mature in the late
autumn/early winter period.
Like the agelenids the tiny species of Hahnia make a sheet web and run about on its top surface.
Their spinners are arranged in a transverse row that makes them instantly recognisable (Fig. 2-5) -
although some species are so small that you might well need a lens to see this. Both the pale H. helveola
and the smaller dark H. montana seem to be widespread in the Forest leaf litter.
The Theridiid Pholcomma gibbum (Fig. 2-6) is quite common in the leaf litter, but also in litter at
the base of grass and heather. The tiny spider has a very characteristic eye pattern rather like that of
Pholcus, the 'Daddy-Long-Legs' spider and its globular abdomen contrasts with the much smaller
cephalothorax. The male has a scutum, a sclerotized plate, on the dorsal and ventral surfaces of its
abdomen.
Tapinocyba species are tiny linyphiid spiders. I have found T praecox to be numerous in the leaf
litter under ancient Beech pollards near Sunshine Plain. This is an unusual habitat for the species
which is usually to be found in grassland. The very local T. insecta is found in leaf litter but has not
been recorded in the Forest. The rather ant like Microneta viaria was thought to be quite a rare spider
when first recorded in the Forest by Frank P. Smith. It is very common in the leaf litter here and is
now known to be a widespread species generally.
There are a number of Lepthyphantes species found in leaf litter. L. flavipes and L. zimmermanni
are common in the Forest together with the ubiquitous L. tenuis and much less common L. tenebricola.
L. minutus seems to prefer drier places and is usually found in piles of brushwood or under rotten logs
on the ground and at the base of tree trunks or in the brush that sometimes grows out of the side of
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