Summary details for Tuberta maerens (O.P.-Cambridge, 1863)

Distribution

Old records for this species exist from Bloxworth, Dorset in 1862 and 1879, and from Bagley Woods, Berkshire. In the 1980s, the spider was recorded from Wytham Woods and Little Wittenham Wood in Berkshire; Brasenose Wood, Oxford; Horton Common, Dorset; Chobham Common, Surrey and Savernake Forest, Wiltshire. In Europe it has been recorded from Italy, France, Germany, Austria and Hungary.

Habitat and ecology

Hambler (1995) has shown that T. maerens appears to be highly specialised to particular microhabitats. It seems to favour fissured bark on tree trunks where it spins a small, fragile funnel web. An open broad-leaved woodland habitat, where tree trunks are relatively warm and dry, offers suitable microclimatic conditions for the spider. It has also been found, once, on Scots pine and there have been a few records of the spider being found under bark on oak and pine. The single specimen from Horton Common was in a pitfall trap on heathland, but close to the boundary where there were old oaks. Females are adult throughout the year and males from July to October.

Status

The species has only been recorded from one 10-km square post-1992. Known from eight locations prior to 1992 but from only two since that date (Hambler, 1995). Though rare and local, work by Hambler (1995) on the habitat of Tuberta maerens suggests it may be commoner than its present status rating suggests.

Threats

The planting of conifers at Bagley Wood will almost certainly have reduced the amount of suitable habitat for this spider. It is not clear whether the introduction of short rotation coppice at Brasenose Wood has adversely affected the species at this site.

Management and conservation

Evans and Hambler (1995) suggest that coppice on a twelve year rotation is probably of greatest benefit to T. maerens, although the highest population of the spider found during their research was found on permanently exposed trees on the woodland paths. Text based on Dawson, I.K., Harvey, P.R., Merrett, P. & Russell-Smith, A.R. (in prep.).