Ars Technica - Yes, this prehistoric fish actually had a buzzsaw of spiraling teeth
Annalee Newitz decided to write something about one weird prehistoric animals. If this was a cartoon, I’d imagine myself using this little fishy’s mouth to cut logs, like something out of the Flintstones. I’d bet that no one imagined they would ever find something like Helicoprion before it was discovered.
LOOK INTO MY TEETH AND DESPAIR. Ray TrollNicknamed the “buzzsaw shark,” this 270 million-year-old creature is actually an extinct relative of the ratfish called a Helicoprion. Its bizarre tooth arrangement has confused scientists for over a century, but one artist finally got it right.
Ray Troll, whose art show about Hilicoprion has been touring the US for the past three years, has been on the front lines of scientific research about one of the strangest fossils ever found. When geologist Alexander Petrovich Karpinsky discovered the creature’s tooth whorl in 1899, at first he thought it was a kind of ammonite because the teeth looked so much like the ammonite’s spiral shell.
Paleo expert Brian Switek writes that it took Karpinsky a little while to realize that it was actually part of a larger animal. Over the next century, many different paleontologists offered explanations for what it might be, including a defensive formation on Helicoprion’s nose, a ridge on its back, or even sticking out of its mouth like a spiky, curled tongue.