homehome Home chatchat Notifications


Large-mouth fish roamed the Cretaceous Seas

They may have had huge mouths, but they fed on plankton - an international team of researchers has found evidence of two new plankton-eating fossil fish species.

Mihai Andrei
February 9, 2016 @ 7:01 pm

share Share

They may have had huge mouths, but they fed on plankton – an international team of researchers has found evidence of two new plankton-eating fossil fish species. The two species lived in the Cretaceous period, about 92 million years ago.

CREDIT: ROBERT NICHOLLS IMAGE

No great extinction or burst of diversity separated the Cretaceous from the Jurassic Period that had preceded it. In some ways, things went on as they had. Dinosaurs great and small still roamed the Earth, pterosaurs and early birds flapped their wings, and marine reptiles hunted ammonites and belemnites in the seas. But not all large marine creatures hunted. Kenshu Shimada, a paleobiologist at DePaul University described two new species from the Rhinconichthys, one from England and one from North America.

Rhinconichthys was thought to be very rare, but considering that another fossil from Japan was also re-described, it seems this wasn’t so much the case.

“I was in a team that named Rhinconichthys in 2010, which was based on a single species from England, but we had no idea back then that the genus was so diverse and so globally distributed,” said Shimada.

Rhinconichthys was estimated to be more than 6.5 feet and fed on plankton. It was one of the largest bony fish to ever roam the Earth. Its most distinctive characteristic was the large mouth and its unusual structure. A pair of bones called hyomandibulae formed a massive oar-shaped lever to protrude and swing the jaws open extra wide, like a parachute, in order to receive more plankton-rich water into its mouth. This type of feeding still exists today, in manta rays and whales.

“Based on our new study, we now have three different species of Rhinconichthys from three separate regions of the globe, each represented by a single skull,” Shimada noted. “This tells just how little we still know about the biodiversity of organisms through the Earth’s history. It’s really mindboggling.”

Journal Reference: Highly specialized suspension-feeding bony fish Rhinconichthys (Actinopterygii: Pachycormiformes) from the mid-Cretaceous of the United States, England and Japan.

share Share

A Woman Asked ChatGPT for a Palm Reading and It Flagged a Mole That Might Be Cancer

A viral TikTok recounts the story of a young woman who turned to ChatGPT for love advice but received an unsolicited medical advice instead.

This School Was Built from Sugarcane Waste. It Might Change Construction Forever

Bricks made from sugarcane waste have constructed a school in India — and are building new vision for construction.

Japan Plans to Beam Solar Power from Space to Earth

The Sun never sets in space — and Japan has found a way to harness this unlimited energy.

Everyone else’s opinion is secretly changing yours (and that's huge for disinformation)

Public opinion may be swaying you a lot more than you think.

Magic Mushroom Use Is Soaring in the U.S. With More Americans Turning to Psilocybin Than Cocaine or Meth

Use is up across all age groups, with rising poison calls and shifting perceptions

Plastics that melt in the ocean offer new hope for cleaner seas

One day we can say goodbye to microplastics.

A Forgotten Civilization in Peru Buried Its War Dead Like Heroes and Now We’re Finally Learning Who They Were

Battle-wounded skeletons and ancient textiles offer new clues about the lesser-known Chuquibamba.

Giant Planet Was Just Caught Falling Into Its Star and It Changes What We Thought About Planetary Death

A rare cosmic crime reveals a planet’s slow-motion death spiral into its star.

These Male Octopuses Paralyze Mates During Sex to Avoid Being Eaten Alive

Male blue-lined octopuses paralyze their mates to survive the perils of reproduction.

These 400,000-Year-Old Mammoth Tusks Carved by Early Humans May Be the Oldest Evidence of Prehistoric Intelligence

Ancient tusk fragments hint at early social learning 400,000 years ago