The families of British spiders


L. Watson and M. J. Dallwitz


Pirate Spiders.

Morphology. The adult spiders 2.4–4 mm long; decidedly plump-bodied; decidedly short-legged, or with legs of medium length, or decidedly long-legged (from about i.5 to three times the body length); with eight eyes. The eyes in two horizontal rows of 4; all clear and glassy. The palpal organs of the male of complex structure and enclosed by the specialized, hollowed tarsal segment (the cymbium). The first two pairs of legs having the tibia and metatarsus armed with long spines, these forwardly-curved towards their tips and increasing in length acropetally along the row, between which are single rows of shorter curved spines. Metatarsus IV of the females without a calamistrum. Tarsal claws 3. The abdomen conspicuously patterned dorsally; exhibiting red or pink colour, but neither predominantly bright red and black nor predominantly bright red and yellow (variegated black, red and white - the red colouring in Blackwall's illustrations appears to be exaggerated). The abdomen of the females without a cribellum. The reproductive openings of the females associated with an epigyne.

The adults making snare-webs (temporary only), or not making snare-webs (specialising in entering the webs of other spiders, and mimicking their prey in order to capture and devour them).

British representation. 4 species in Britain; in the genus Ero.

Illustrations. • Ero sp..

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.’.