LONDON (NYTIMES) - Millions of years before the Cotswolds, in western England, became a popular vacation destination, romanticised for its ancient woodlands, honey-coloured stone villages and medieval abbeys, it was a shallow, warm sea, home to a Jurassic marine ecosystem.
More than 167 million years later, amateur palaeontologists Neville and Sally Hollingworth uncovered fossils in a limestone quarry there, the largest find of Jurassic starfish and their relatives ever to be made in Britain.
More than 1,000 scientifically significant specimens were unearthed at an undisclosed location during a three-day excavation last month, London's Natural History Museum said in a statement. The site is not being revealed for security reasons.
The find by the Hollingworths, a husband-and-wife team, includes three new species and an entire ecosystem of echinoderms - a group of animals that includes starfish, brittle stars, feather stars, sea lilies, sea cucumbers and echinoids. Fossils of such animals are extremely rare because they have fragile skeletons that are not often preserved.
The exquisite detail of the collected fossils capture the creatures' last moments before they were buried by what experts have said could have been an underwater mudslide.
Dr Neville Hollingworth, 60, is not new to fossil hunting. He discovered his first fossil - a small opalescent ammonite - in Somerset, in south-west England, when he was 12, which ignited a passion for palaeontology and led to his getting a doctorate in the subject.
"I went fossil collecting every day," he said. "A lot of my friends thought I was odd."
The Hollingworths met in 2016 at a local science festival under the skeleton of a Gorgosaurus, perhaps foreshadowing the couple's big discovery.
While many people turned to sourdough and banana bread recipes to keep occupied through three Covid-19 pandemic lockdowns in England, the couple scoured Google Earth to pinpoint the site of their next excavation.
The location the Hollingworths identified last August was a privately owned limestone quarry surrounded by Jurassic rock beds. The site had been mentioned in research papers published more than a century ago as a place where some marine fossil specimens had been found.
Lockdown restrictions, however, meant that the couple were not able to visit the quarry until November.
Dr Hollingworth was already familiar with the Cotswolds' geology - he discovered a 1.5m mammoth skull there in 2004. And, in November, after digging less than 0.6m into the quarry's clay, he said, he "instantly recognised" evidence of fossils. "If it was just left, it would be lost," he said.
His wife was more sceptical. "We found really tiny, fingernail-sized fragments of fossils," said Mrs Hollingworth, 50, who works in accounting for a construction company.
"I was going to have a cup of tea," she said, laughing. "It was all a bit boring."
But Dr Hollingworth would not be deterred. While he expected little from the excavated slabs of clay, he said, he still spent hours in his garage removing layers of sediment, grain by grain, with a micro-sandblaster. Then he caught a glimpse of a sea lily fossil.
"The whole block came alive," Mrs Hollingworth said. "I've never seen anything like it."
Describing the sea lily fossil, Dr Hollingworth said: "They've got this beautiful, ornate crown cup, and little, tiny feather-like projections sticking out of them. The minutest detail is preserved beautifully."
He promptly reached out to a senior curator at the Natural History Museum with whom he had become acquainted on previous digs. Dr Hollingworth invited the curator, Dr Tim Ewin, to visit the excavation site, enticing him by e-mail with photographs of the fossils.
"To my joy and surprise, they were beautifully preserved fossils - sea urchins, starfish and some really rare feather stars," Dr Ewin said.
"In the Natural History Museum collections, we don't have any complete specimens of those types of fossils, so I knew instantly it was important," he added.
A winter lockdown and inclement weather causing flooding at the quarry delayed the museum's excavation of the site until June. But the find's significance was swiftly recognised.
"The museum collection previously only had 25 incomplete specimens," Dr Ewin said. Now, there are about 150 complete specimens from the Cotswolds site alone.
Among the echinoderms found at the excavation site, the feather stars - marine invertebrate crinoids with feathery arms - were the rarest.
"That gives you an idea of how rich in abundance this site is," Dr Ewin added.
In January, on a beach in Wales, a four-year-old girl stumbled across a 200 million-year-old footprint from an unknown herbivorous dinosaur that lived during the Upper Triassic Period. The fossil is now on display at the National Museum Cardiff.
While the Natural History Museum has no immediate plans to put its newest treasures on display, preservation work will probably yield new information about their evolutionary histories. Experts can scan them in 3D, Dr Hollingworth said.
"That will bring a lot of new information on the evolution and the geological history of this truly iconic group," he added.