This one was not one of the commoner species such as the familiar House Spider, but Tegenaria agrestis.
It was first recorded in Britain in 1949 and prefers disturbed brownfield habitats. It is a widespread European species and has a wide but patchy distribution across much of England but there are comparatively few records from Wales. Glamorgan records are restricted to a couple of sites to the West of VC41. It is thought to spread along railway lines, using the track-side ballast as an ideal habitat. Sure enough, the abandoned quarry south of Rhoose village is less than a hundred metres from the Aberdare to Bridgend line that services Aberthaw power station. It is quite likely to be present in other areas of suitable habitat along the railway corridor I guess.
|Tegenaria agrestis distribution|
Source: Spider Recording Scheme/British Arachnological Society (2012) Website and on-line database facility