Mollisonia plenovenatrix preserved in dorsal view, showing the large eyes, the walking legs and the small chelicerae at the front. Alberta’s famed Burgess Shales have yielded another ground-breaking fossil find — this time the oldest known ancestor of today’s spiders and scorpions. (Jean-Bernard Caron-Royal Ontario Museum)

Mollisonia plenovenatrix preserved in dorsal view, showing the large eyes, the walking legs and the small chelicerae at the front. Alberta’s famed Burgess Shales have yielded another ground-breaking fossil find — this time the oldest known ancestor of today’s spiders and scorpions. (Jean-Bernard Caron-Royal Ontario Museum)

‘Staring at me:’ Oldest known spider ancestor found in B.C.’s Burgess Shale

‘I turned my head to the right and I see this glowing light coming from this rock’

Tiny eyes blinking at him from the rockface of the Burgess Shale near Field, B.C., drew Jean-Bernard Caron to the fossil of the oldest known ancestor of today’s spiders and scorpions.

“I was sitting there along the quarry and I turned my head to the right and I see this glowing light coming from this rock,” he said. “Two eyes, almost staring at me.”

The eyes turned out to belong to a 500-million-year-old specimen of Mollisonia plenovenatrix — so well preserved that Caron and his colleague Cedric Aria were able for the first time to definitively place the long-gone beastie at the root of a family tree that now boasts thousands of branches.

It was only thumb-sized, a scurrier of ancient sea bottoms. Still, the two paleontologists from the Royal Ontario Museum say it would have a been a fierce predator.

ALSO READ: Epic animal fossil discovery in Kootenay National Park

Large eyes spotted prey. Long limbs propelled it across the sediments. Its head was like a modern multi-tool with limbs that could sense, grasp, crush and chew.

The tiny pair of structures in front of its mouth really got Caron and Aria excited.

Those same pincers can be seen on all members of the family Chelicerata. That’s 115,000 different species, and here was their progenitor.

“I was really excited about this,” said Caron, who published his findings Wednesday in the journal Nature.

“Those fossils tell us about the origin of key innovations in animal evolution. It’s important to understand how they happen. Because when they happen, there is often an explosion of life that is the consequence.”

Intriguingly, the species was clearly some distance along its evolutionary path, well-adapted to its environment and breathing through thin gills layered like the pages of a book.

“This discovery tells us that at the time of the Cambrian they were already there,” Caron said. “They probably evolved earlier than that.”

That means there’s probably another, even older ancestor out there — maybe waiting in the same Burgess Shale of southeastern British Columbia.

Those rocks are renowned the world over for their wealth of fossils from the middle Cambrian period, a time when the Earth’s biodiversity exploded. What sets Burgess specimens apart is the clarity with which the soft parts of the animals are preserved.

“I feel like a boy in a candy store,” Caron said. “There are a lot of candies to choose from and the question is which one I’m going to pick and describe first.

“We could work for decades there and still feel we haven’t scratched the surface. There’s still a lot ground we haven’t covered.”

Look for the eyes, said Caron.

“The eyes are very reflective. It’s very striking. Many fossils that we discover in the rocks, the first thing you see are the eyes, like shiny spots in the rock.”

Bob Weber, The Canadian Press

Like us on Facebook and follow us on Twitter.

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

Kootenay-Columbia MP Rob Morrison speaks during Question Period in the House of Commons. File photo.
MP Morrison calls Keystone XL permit cancellation ‘devastating news’

Kootenay-Columbia MP reacts to the Conservative Party’s removal of a controversial Ontario MP

Interior Health reported 91 new COVID-19 cases in the region Jan. 20, 2021 and three additional deaths. (Jennifer Smith - Morning Star)
95 new COVID-19 cases in Interior Health, two deaths

Another member of Vernon’s Noric House has passed

North-West Mounted Police barracks at the top of Douglas Street hill, 1885. The man seated at the front was (Colonel Sam Steele. Revelstoke Museum and Archives photo 856)
Glimpses of Revelstoke’s past for Jan. 21

130 years ago: Kootenay Star, Jan. 24, 1891 An accident occurred at… Continue reading

Liam Harrap, reporter for the Revelstoke Review, gives a sneak peak on what’s making news in Revelstoke. (Jocelyn Doll/Revelstoke Review)
A sneak peak at the Jan. 21 news paper

Pick up your copy on news stands today

Voting is the number one, bare minimum way to have your voice heard by government. (File photo)
Jocelyn’s Jottings: Want to make change? Here are some suggestions

As a citizen you have a voice, you just have to know who to talk to

Liam Harrap, reporter for the Revelstoke Review, gives a sneak peak on what’s making news in Revelstoke. (Jocelyn Doll/Revelstoke Review)
A sneak peak at the Jan. 21 news paper

Pick up your copy on news stands today

Premier John Horgan leaves the podium following his first press conference of the year as he comments on various questions from the media in the Press Gallery at B.C. Legislature in Victoria, B.C., on Monday, January 13, 2020. THE CANADIAN PRESS/Chad Hipolito
Interprovincial travel restrictions a no-go, Horgan says after reviewing legal options

The B.C. NDP government sought legal advice as concerns of travel continue

Kevin Lee Barrett is charged with attempted murder and aggravated assault. (Facebook)
Court hears of victim’s injuries in West Kelowna attempted murder trial

Two-week-long trial continues for Kevin Barrett, accused of trying to kill mother in West Kelowna

Robert Riley Saunders. (File)
Disgraced Kelowna social worker faces another class-action lawsuit

Zackary Alphonse claims he was not informed of resources available to him upon leaving government care

A mother hold hands with her daughter while sharing about her struggles with addiction during Overdose Awareness Day. (Jesse Major/Black Press file)
Overdose and suicide support group starts in Penticton

Penticton was one of the province’s communities hardest hit by the overdose crisis in 2020

Jan. 21 marks the 21st day of the 21st year of the 21st century, according to some. (Black Press Media file photo)
The 21st day of the 21st year of the 21st century is upon us

Milestone won’t be back for another 100 years

Join Black Press Media and Do Some Good
Join Black Press Media and Do Some Good

Pay it Forward program supports local businesses in their community giving

The steel mills in the Hamilton waterfront harbour are shown in Hamilton, Ont., on Tuesday, October 23, 2018. THE CANADIAN PRESS/Nathan Denette
Dyer: Stay the course on Carbon pricing

Kristy Dyer has a background in art and physics and consulted for Silicon Valley

Gem Lake Top, at Big White Ski Resort, seen at Jan. 8. (Big White Ski Resort)
Big White cancels $7.3M in lift tickets, accommodations due to COVID-19 orders

Since November, the ski resort has been forced to make several changes

Most Read