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NEYEDC improve and inform environmental decision making, conservation, land management and sustainable development in North and East Yorkshire through the collation, management, analysis and dissemination of biodiversity information.

The Natural History of Yorkshire in 100 Species

Explore the rich and diverse natural history of our region through the stories of 100 species, told by the people who know them best.

#9 Russet Funnelweb Spider by Dr Geoff Oxford

Meet Dr Geoff Oxford, Honorary Fellow at the University of York!

Geoff Oxford is currently an Honorary Fellow in the Department of Biology, University of York, where he taught genetics and evolution for nearly 40 years. He has been interested in spiders for almost half a century and is an active Council member of the British Arachnological Society, for whom he has served as both President and Hon. Secretary. He is an author of the 2017 photographic field guide, Britain’s Spiders. You can find the British Arachnological Society on twitter at @britishspiders, and find our more about the Society and their work on their website.

An ‘Elvington enigma’, Geoff’s chosen species is the Russet Funnelweb Spider Tegenaria ferruginea. The Russet Funnelweb Spider is related to the much more familiar large house spiders (Eratigena species) we all see running across floors in late summer. Its closest relative, however, is the Cardinal Spider Tegenaria parietina, an extremely long-legged species confined to the southern counties of England. The Russet Funnelweb Spider is a large species with male body lengths 9-11 mm, and those of females 11-14 mm. The most noticeable characteristics of the spider is the overall reddish coloration - especially the russet stripe down the middle of the abdomen - and the beautifully marked, banded legs. Visually, it is a stunning species.

Female Russet Funnelweb Spider, showing their incredible markings.

It builds a typical funnel web using deep, silk-lined crevices in Yews and other trees as its retreat, and spreads a prey-catching sheet of silk out and over adjacent twigs and branches. In 1998, a thriving population of this spider was found in Holy Trinity churchyard in Elvington by Geoff, some 10km southeast of York. Amazingly, this was not only a first record for this species in Britain, but remains its only known location in the entirety of the UK – a true Yorkshire speciality.

At the time, in 1998, Geoff was out surveying the distribution of the common large house spiders Eratigena saeva, E. duellica and their hybrids in Yorkshire, including in the churchyard in Elvington. On stimulating a web (in those days by throwing in an angler’s maggot!), much to his amazement, a reddish, banded leg appeared. It was definitely not one of the species sought on the survey, whose legs are uniformly coloured. It was also too bright and too far north to be a Cardinal Spider…so what was it? To answer the question, one or two specimens were enticed out, raised to maturity, and formally identified. This led to the amazing discovery of Tegenaria ferruginea, a first for the UK.

If the life cycle of the spider is like that of closely related species, it matures in late summer. After mating, the male dies and the female overwinters with stored sperm. In spring, when temperatures and invertebrate prey both increase, the female lays a succession of egg sacs in or near her retreat. The young that emerge will spend the next winter as half-grown juveniles, maturing the next year. What little we know if its phenology in Elvington fits with this pattern.

The origin of this population is an enigma. However, the airfield at Elvington (now home to the Yorkshire Air Museum) was an RAF Bomber Command station during the Second World War. In 1944, two French squadrons were posted there and it is possible that the incoming aircrews inadvertently introduced the spider, which is widespread in France. If so, why they ended up in the churchyard is anyone’s guess!

Monitoring

Elvington church and churchyard, the only known site for this species in the UK.

While the Elvington population is the only one known in Britain, the species is widespread in continental Europe and globally is not endangered. The Yorkshire population was mapped on its discovery in 1998, when it extended out from the churchyard to encompass adjacent hedge and fence bottoms. A second survey in June 2018 confirmed the species’ continued presence but, interestingly, no evidence of it spreading over time to beyond this small area. There is no formal monitoring in place for this species specifically, however the British Arachnological Society have a spider recording scheme that welcomes records of spiders and harvestmen in the UK.

Further information and acknowledgements

NEYEDC would like to thank Geoff for his time and expertise in helping to create this blog, and for providing the wonderful photos of this species. If you’d be interested in contributing a piece for the series, contact Lucy at lucy.baldwin@neyedc.co.uk. To find out more about biological recording, see the Naturalists page on our website.

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