The families of British spiders
Morphology. The adult spiders 4–15 mm long; of medium build, or decidedly plump-bodied; decidedly short-legged, or with legs of medium length (about as long to about 2.5 times as long as the body); with eight eyes. The eyes in two horizontal rows of 4; all clear and glassy (light in colour). The palpal organs of the male of complex structure and enclosed by the specialized, hollowed tarsal segment (the cymbium). Metatarsus IV of the females with a dorsal series of curved bristles (the calamistrum, which is reduced in the males); the bristles in two rows. Tarsal claws 3. The abdomen conspicuously patterned dorsally. The abdomen of the females furnished with a plate-like cribellum anterior to the spinnerets (this being reduced in the males).
The adults making snare-webs; constructing tangled webs (these fuzzy, with a circular retreat, in walls or tree bark).
British representation. 3 species in Britain; in the genus Amaurobius.
Illustrations. • Amaurobius fenestralis, with dissections. • Amaurobius fenestralis and A. similis. • Amaurobius ferox. • Amaurobius ferox.
To view the illustrations with detailed captions, go to the interactive key. This also offers full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, and distributions of character states within any set of taxa.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2003 onwards. The families of British spiders. Version: 4th January 2012. http://delta-intkey.com’.