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Family : Gnaphosidae
New Genus : EDA
New Species : Gnaphosidae EDA sp EDA
♀5.5mm
EDA LOGYARD 18-11-2014 TUE 9:45AM
Family: Gnaphosidae (Ground Spiders)
Biology: The Gnaphosidae is the seventh
largest spider family of the world encompassing ca. 2000 species in
8 subfamilies and 114 genera. They range in size from small to large
(2-18 mm body size). The species are free-living found mailnly at
ground level in open habitats but some species are house spiders,
for example Scotophaeus blackwalli in the northern parts of its
distributional range. They build a tubular retreat, from which they
leave at night to hunt prey. The female guard her papery egg sack
hidden in small holes under logs, stones, etc. Most species are
active at night, however spiders of the somewhat atypical genus
Micaria are diurnal hunters running rapidly about in bright
sunshine.
Characters of family: The gnaphosids are
rather stout ecribellate spiders with a flattened and elongate
abdomen.
Carapace:
The carapace is ovoid and rather low being smoothly convex
and with a distinct fovea (a small depression 凹) at behind.
The head is not sharply
set off from the thoracic region. Gnaphosids are fairly easily
recognized by their cylindrical and parallel spinners, the anterior
pair being slightly longer, and more heavily sclerotized than the
posterior pair. The anterior spinners are separated from each other
by approximately one spinner diameter with some exceptions, e.g.
Micaria in which genus anterior spinners are closer.
Eyes:
8 eyes in 2 rows. The posterior medial
eyes are not round, but oval, triangularly reduced to slits.
All eyes are with a silvery sheen except for the anterior medials,
which are dark.
The curvature of the posterior row of eyes and the position and
shape of cheliceral lamina and teeth are important characters when
keying gnaphosids to genus level under the stereomicroscope.
The Mouth Parts:
The sternum is ovoid, pointed posteriorly 向後.
The
chelicerae are robust, and the fang are short.
The Maxillae (endites) are
provided with a serrula (row or cluster of tiny teeth on the front
margin).
Labium.
Gnaphosids are also characterized by having 2 tarsal claws,
claw tufts, and scopulae.
Legs:
Legs are NOT stout. This is unusual compared with other
species in the same family which usually have stout legs as a ground
walking spiders.
and in some species there
are small brushes of more and less stiff hairs present distally on
metatarsus IV.
Palp:
Female palp is furnished with small spines and a
finely toothed claw.
The abdomen is often provided with dense
coverage of short sleek hairs giving the abdomen a mousy-like
appearance. Sometimes erect, curved setae are present, particularly
at the anterior edge (see for example images of Gnaphosa lucifuga).
Many species are uniformly coloured in greyish-brown or blackish
colours. However, abdomens of some species have striking white
patterns of spots or lines while abdomens of others are iridescent.
Most males have a scutum at the anterior end. The spiracle is
situated close to the spinners. Gnaphosids are entelegyne spiders
often having rather large epigynes with sclerotized structures. They
are somewhat variable and closely related species may be difficult
to identify. Male palps are usually provided with a large tibial
apophysis and the shape of this is important when identifying the
species.
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