‘White-knuckled wolf spider’ thought lost is rediscovered on Isle of Wight

A tiny spider thought to have vanished for ever from the UK has been rediscovered on a remote area of a nature reserve accessible only by boat.

The Aulonia albimana, a member of the wolf spider family with orange legs, was found on the Isle of Wight in a spot grazed by a flock of Hebridean sheep.

It previously had no common name but has been called the white-knuckled wolf spider because of the distinctive pale “knuckles” on its palps (the small leg-like appendages either side of the mouth) and the last-minute drama involved in finding it.

It was rediscovered more than a mile from its former colony at the National Trust’s Newtown national nature reserve by the entomologists Mark Telfer and Graeme Lyons. Telfer, who led the survey, said: “This is one of those unforgettable discoveries. To find a species thought lost for 40 years is thrilling.”

Lyons said they had just four hours at the site before their boat was due to pick them up. “I found the first one with just nine minutes to go, and the second one in the last minute,” he said. “I’ve seen 559 species of spider in the British Isles and this one was by far the most exciting find.”

Wolf spiders – of which there are about 38 species in the UK – take their name from their agile hunting skills, which involve chasing prey along the ground and then pouncing like a wolf.

However, the hunting techniques of the diminutive Aulonia albimana – adults’ body length typically measures 3.8-4.4mm – remain something of a mystery, as the species also spins a flimsy web. The spider was last recorded in the UK in 1985.

The site where they were found had become overgrown but was restored by the National Trust with the Hebridean sheep, which chew through vegetation to maintain short, open turf, creating exactly the kind of patchy, sunlit ground the spider favours.

Graeme Lyons and Mark Telfer found the spider at Newton national nature reserve. Photograph: Graeme Lyons

Helen Smith, the conservation officer for the British Arachnological Society, said: “The remarkable discovery of this dapper little spider on the Isle of Wight is one of Britain’s lost species rediscoveries of the century.

“With repeated failure to find it at its former sites, where its open habitat has been lost, it seemed increasingly likely that it had joined the country’s sad list of extinct species.”

The next task is to establish the full extent of the population and determine the conditions it needs to expand its range and secure its future.

Paul Davies, the countryside manager for the National Trust on the Isle of Wight, said: “We’ve been managing this rare limestone grassland for years to encourage a rich diversity of wildlife. To see that work paying off with the return of a species this rare is incredibly rewarding.”