of the tall grass stems and heather. The spider waits in a retreat to one side of the orb web at the end
of one of the supporting silk lines.
Nearly half the species of spider found in Britain are linyphiid or 'money' spiders. The males of
many of these spiders are remarkable for their various extraordinary and curious elevated heads with
pits and grooves (e.g. Figs. 1 -3 to 1 -5). The female in some species is known to use the pits and grooves
to help grip her mate and in at least one related species it has been shown that the female draws blood
from the male during copulation! This would seem to be a method of appeasing the predatory instincts
of the female so that the male can survive to mate again.
The tiny Peponocranium ludicrum males with their 'ludicrously' extended heads (Fig. 1-4) are
numerous on Sunshine Plain in early summer at the base of grass tussocks and in the litter under the
heather. Later in the summer the females seem to move up into bushes, probably to lay and guard their
egg sacs.
A number of Walckenaeria species occur in the areas of wet heathland. Walckenaeria furcillata (Fig.
1-3), a species rare in Essex, is recorded from Deershelter Plain and Walckenaeria vigilax, W.
atrotibialis, W unicornis and W. acuminata (Fig. 1-5) are probably all widespread in the heathland
and grassland habitats of the Forest.
The very common linyphiid spider Pocadicnemis juncea is numerous in grassland areas but the
closely related P. pumila sensu stricta seems to be confined in Essex to areas of relic heathland in the
Forest area and some woodland rides on the boulder clay in the north-west of the county.
Lepthyphantes mengei seems to be fairly numerous in heathland areas in the Forest. It is another
species generally believed to be common but which in Essex appears to be rather local.
Woodland Habitats
Many woodland spiders inhabit the foliage and branches of trees as subadults and adults. These
spiders are usually found in the woodland edge habitat of clearings or rides, but this may be because
this is where arachnologists can reach the branches of the trees. There is much scope for ecological
work to be done on the spider fauna to be found in the tops of trees!
Spiders are predators and they are predators that are not usually particularly fastidious about the
exact nature of their prey. This would suggest that they would not show much preference for particular
species of tree. However there often seem to be greater numbers of spiders to be found in the lower
branches of Oak than other trees like Beech and Hornbeam. I suppose that this could be related to the
availability of prey, or the nature of spacial areas available for webs, or the protection offered by
different leaf shapes and sizes.
Foliage is home to species like Anyphaena accentuata the 'buzzing spider' a hunter that can move
and pounce rapidly. The male vibrates his abdomen against the leaf surface as part of his courtship to
the female producing a clearly audible buzzing sound (Bristowe, 1958). In the autumn, winter and
spring the immatures are found in the leaf litter and around the bases of trunks where leaves
accumulate.
Philodromus praedatus is a crab spider found, for example, on the oaks at the side of Sunshine
Plain. This species was formerly known from only a very few specimens taken in both Britain and
Europe. Recent years have shown the spider to be much more widespread than previously thought
and it has now been newly recorded from the Netherlands (Peeters and Meyer, 1986), Belgium (Segers,
1987) and Sweden (Jonsson, 1990) as well as from many new localities in Britain. Philodromus
spiders, especially females of the aureolus group, are notoriously variable and difficult to determine
especially in the field and the species must have been widely overlooked in the past. At the moment
it looks as though the species is nearly always found on large Oak trees whereas P. aureolus is more
often associated with scrub Oaks and Pines and P. cespitum with scrub such as Hawthorn and Gorse.
Ballus depressus is a squat little jumping spider that is found in the foliage of trees and bushes. Like
other jumping spiders the adult male is a very different looking spider to the female. In courtship the
male sways from side to side and draws in his swollen front legs (Bristowe, 1958).
A number of Theridiid spiders are common in foliage. Theridion pallens is a tiny pale spider with
darker markings that in very common especially on Oak trees. The female makes a curious spiky
eggsac on the underside of a leaf (Fig. 2-1). T. tinctum is a spider believed not to make a web itself
but to raid the webs of other species and to prey on the owner rather in the manner of the pirate spider
Ero.
Both the bright green Araneid spiders Araniella cucurbitina and A. opistographa are found in the
Forest where they make their small orb webs across just one or sometimes several leaves.
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