Gnaphosa modestior - Danish Spiders

Gnaphosa modestior

≤ 1900

1901-1979

1980-2005

2006 ≤

Size: Female ? mm; male ? mm.

Genus: Gnaphosa Latreille, 1804. Characters of genus: Most species with dark brown cephalothorax. The abdomes is either dark brown, greyish-black or black, thickly covered with grey hairs. The genus is characterized by having the posterior row of eyes recurved.

Family: Gnaphosidae Pocock, 1898 (Ground Spiders). Characters of family: The gnaphosids are rather stout ecribellate spiders with a flattened and elongate abdomen. The carapace is ovoid and rather low being smoothly convex and with a distinct fovea in most species. 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. They have 8 eyes in 2 rows. The posterior medial eyes are often not round, but oval, triangular or reduced to slits. All eyes are with a silvery sheen except for the anterior medials, which are dark. The sternum is ovoid, pointed posteriorly. The chelicerae are robust, and the fang furrows are provided with teeth. The retromargin may have a sclerotized lamina (flat, keel-like plate) in place of teeth. This lamina is serrated in some genera. 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 endites usually have an oblique or transverse depression. They are provided with a serrula (row or cluster of tiny teeth on the front margin). Gnaphosids are also characterized by having 2 tarsal claws, claw tufts, and scopulae. Legs are stout and in some species there are small brushes of more and less stiff hairs present distally on metatarsus IV. 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.