The families of British spiders

DELTA Home

L. Watson and M. J. Dallwitz

Theridiosomatidae

~Araneidae.

Orb Weavers.

Morphology. The adult spiders 1.5–2.5 mm long; decidedly plump-bodied; decidedly short-legged; with eight eyes. The eyes in two horizontal rows of 4, or in an oval cluster; all clear and glassy. The maxillae about as long as broad. The palpal organs of the male of complex structure and enclosed by the specialized, hollowed tarsal segment (the cymbium). The female palps without a claw. The first two pairs of legs without the spines characteristic of Mimetidae. Metatarsus IV of the females without a calamistrum. Tarsal claws 3. Tarsus IV without a ventral ‘comb’. The abdomen conspicuously patterned dorsally (darkly, on the silvery background). The abdomen of the females without a cribellum. The reproductive openings of the females associated with an epigyne.

The adults making snare-webs; constructing orb webs (these horizontal and umbrella shaped, in damp marsh vegetation).

British representation. 1 species in Britain; in the genus Theridiosoma (T. gemmosum). Widespread (but restricted to southern England, southern Wales, and southern Ireland).

Comments. The globular abdomen of T. gemmosum is marked with silver in both sexes.


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’.

Contents