The families of British spiders
Morphology. The adult spiders 3.5–18 mm long; of medium build; decidedly short-legged, or with legs of medium length (but rarely reaching twice the body length); with eight eyes. The eyes ostensibly in three rows of 4+2+2, the anterior row of four more or less recurved (4+2+2: configured as an anterior, somewhat recurved row of four small eyes, and behind it four equal-sized, larger ones forming a trapezium). The palpal organs of the male of complex structure and enclosed by the specialized, hollowed tarsal segment (the cymbium). The trochanters of all the legs notched. Metatarsus IV of the females without a calamistrum. Tarsal claws 3. Tarsus IV without a ventral comb. The abdomen conspicuously patterned dorsally. The abdomen of the females without a cribellum. The reproductive openings of the females associated with an epigyne.
The adults constructing a terrestrial retreat in the form of a silk tube (in some species), or constructing neither a terrestrial silken retreat nor an underwater diving-bell (although some - e.g., Pirata and Arctosa species living in wet places - build burrows or silken retreats that are regularly inundated, or open at or only just above the surface of the water); not making snare-webs; actively pursuing their prey (mostly ground runners). The females carrying egg sacs attached to their spinnerets (and carrying the young for several days after the eggs have hatched).
British representation. 36 species in Britain; in the genera Alopecosa, Arctosa, Aulonia, Hygrolycosa, Pardosa, Pirata, Tricca, Trochosa, and Xerolycosa.
Illustrations. • Trochosa ruricola and T. terricola. • Alopecosa barbipes and A. pulverulenta. • Arctosa cinerea, Arctosa perita. • Arctosa leopardus. • Pardosa amentata. • Pardosa saltans and Pardosa agricola. • Pardosa palustris. • Pirata hygrophilus, P. latitans, and P. piraticus.
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’.