Tegenaria sp.  (AGELENIDAE)

This family includes the large house spiders, often seen running on the carpet of the living room in dwellings in the UK. They live in funnel webs, often in dark corners of rooms. There are eight species of Tegenaria listed in Reference 3, identified as resident in Britain, but many more worldwide. Since publication of the reference the family has been spit into two sub-families - Tegenaria and Eratigena. Identification has been made more complicated recently by the discovery that some species can hybridise. The identifications allocated to the micrographs should be regarded as a "best guess" and suggestions for corrections are welcome.

Head and chelicerae of Tegenaria duellica. The bottom end of the chelicerae of ?Tegenaria duellica. Note the clearly visible holes in the fangs through which venom is injected into the prey. The number and size of the visible teeth suggests that this might in fact be one of the Eratigena sp. Futher investigation into this specimen is required. Left Pedipalp (male sexual organ) of Tegenaria saeva.

Epigyne (female sexual organ) of Tegenaria duellica. Spinnerets of Tegenaria duellica. Tarsal claw of Tegenaria saeva. The central hook can be clearly seen, but there is no evidence of any serrated bristles. Instead, the hairs are more bristly than normal, possibly fulfilling a similar function. The web of this family is very messy, so perhaps the hairs alone are sufficient to grip it.