Meet the giant 8-million-year-old fossil crab named Karl

Compared with nine million years, sixteen years is a drop in the ocean.

But that's how long Karl Raubenheimer has been waiting to have a fossil he found to be officially recognised.

The species has just been named after him – the Pseudocarcinus karlraubenheimeri.

“So that’s pretty cool, it's named after me, the species," he smiled.

"It’s a very long name, sorry, but that’s my name.”

It was 2008 when Raubenheimer discovered the remains of a giant crab inside a rock on a beach in North Taranaki, while on a fossil-hunting field trip with his science teacher.

“I was going along the beach. When I found the rock, I knew something was in it. But I called Mr Buchanan-Brown over. I could see his excitement — he was more excited than I'd ever seen him. And jealous, so that was good.

"I knew I’d found something special."

His old science teacher recalled the moment.

"We'd been on the beach for about an hour, hour and a half, and hadn't found much, a few bits and pieces. Then I found this fairly large boulder, put it up on its edge, thought I'd probably get around to it later, and went and had a smoko.

"Then Karl found it and said, ‘We've got to crack this one’. We cracked it open and there was this enormous crab inside it."

It may be one of the biggest crabs ever to have lived, likely weighing around 12kg — more than the average car tyre — and sporting a menacing 30cm long claw.

“This crab is phenomenal, it's one of the biggest crabs in the world if not the biggest. It's a special crab,” said Raubenheimer.

The fossil is estimated to be around 8.8 million years old. “It could be older; it could be about 11 or 9 [million], somewhere around there. It’s close enough, within a mil.”

To have his find officially recognised has been a long process. First, Raubenheimer had to find other specimens to ensure it wasn’t a random deformity.

"It took me another ten years to find nine other species. I have ten of these in total," he said.

Raubenheimer worked closely with an international crab expert, Barry van Bakel.

“He’s in Germany, he’s the crab guy. He’s done a lot of work on this. You can’t send the whole rock over.

"We sent him some moulds and some photos. He’d be messaging me at 3am saying, ‘Can you measure the tip of the claw?’ I was like, ‘Yeah, sweet’. Or, ‘Can you count the different bumps on the head’. We’d go back and forth."

The findings not only had to be verified but cross-referenced with all other registered finds.

“Barry’s work had to be peer-reviewed. It goes back and forth with amendments. He’d submit the paper and then it gets peer-reviewed.”

Finally, 16 years later the find has been officially recognised.

“I woke up to my phone showing hundreds of calls and messages. It’s cool. It’s very exciting.”

The biggest pieces of Raubenheimer’s fossil are at Te Papa.

“The two best types have to go to the museum so people can see it.”

He’s kept a smaller piece to add to his enormous fossil collection, which includes penguin and seal bones.

“The coolest thing about fossils is that it’s a window into the past, you get to see things you couldn't imagine," he said.

“They can tell us about global warming, speciation, what life was like post-ice-age. We can learn about climates and also about geology. It can tell us where and when earthquakes were happening.”

His old science teacher held no bitterness over his ill-timed cigarette break that day.

“That was back when I used to smoke. I thought I’d stop for a quick roll-up. In hindsight, I wish I hadn’t!" said John Buchanan-Brown, who has himself had plenty of success with fossil hunting, including the discovery of a new species of petrel.

“As horribly jealous as I am about the whole thing. I think it's brilliant. I'm very proud of him and proud of his achievement. It's a hell of a thing to do," he admitted.

“The work he's done over decades, finding other specimens, getting them to the right authorities at Te Papa and abroad, getting the specimens cleaned up and prepared.

"It’s an awful lot of work. He should be very proud of himself. It’s not just new to New Zealand but to the world. And that’s special."

When Raubenheimer's not digging, he’s gigging, as a musician in The Blistered Fingers.

“We’ve tried to write songs about fossils but it gets too much. I think you could do it if they [the audience] knew a little about fossils, but then you go too deep and everyone goes, 'Nah, that doesn’t work'.”

But Raubenheimer's real passion is palaeontology.

“I was 10 when Jurassic Park came out — that pretty much changed my life.”

Raubenheimer wouldn’t say exactly where he found his record-breaking specimen, other than it’s somewhere in North Taranaki. “I'll keep the beach secret until we've done more work on it.”

He may have discovered the biggest crab the world's ever seen, but he's now aiming even bigger.

“I will find a dinosaur one day.”