Scientists may have finally found an explanation for the baffling, blob-like sea creature dubbed the “alien goldfish.” Without spine, anus, eyes or shell, Typhloesus wellsi has baffled researchers for decades.
“[Typhloesus] was kind of an orphan in the tree of life,” says Jean-Bernard Caron, curator of invertebrate paleontology at the Royal Ontario Museum Guardian‘s Nicholas Davis. Since its first observation, experts have attempted to place the creature below its evolutionary relatives.
But in a new study published in biology letters, Caron and his colleague, paleontologist Simon Conway Morris of the University of Cambridge in England, describe the discovery of a tooth-like structure in the animal’s gut, suggesting that the organism is a type of mollusk. Modern molluscs have a similar set of teeth called a radula that they use to feed.
Caron and Morris discovered the structure while examining about a dozen specimens held at the Royal Ontario Museum, many of which had never been analyzed before Guardian. The tooth-like structure is about 4 millimeters long with two rows of 20 triangular teeth. It was previously mistaken for muscle tissue because it’s found in the creature’s gut, the reports New York Times‘ Jack Tamisiea.
The alien goldfish may have poked the toothy tongue out of its mouth into the water to catch prey, researchers say. “Here’s an analogy [is] the tongue of a lizard, for example, when catching an insect. It’s very fast and it puts food in your mouth,” says Caron Guardian.
T gutsi grew to about 3.5 inches in length and lived about 330 million years ago. The animal’s remains were discovered in Montana’s Bear Gulch limestone fossil deposit in the late 1960s and described in 1973.
Previous researchers identified tiny teeth in some of the alien goldfish fossils, leading them to believe the animal was an extinct eel-like fish called the conodont Times. But on closer inspection, that theory fell flat when the teeth were revealed to be remains T. wellsilast meal in his digestive tract. Now the animal’s radula offers a new clue.
“It’s a very exciting find to have a radula because it definitely is,” says Christopher Whalen, an invertebrate paleontologist at the American Museum of Natural History who was not involved in the new study Times. “Just as all vertebrates have a backbone, all molluscs have a radula.”
But Mark Purnell of the Center for Palaeobiology at the University of Leicester in England says so Guardian that many animal species have independently evolved similar traits, so more research is needed to know for sure if the alien goldfish is definitely a mollusk.
“It’s still a very strange animal,” says Purnell, who was not involved with the new paper Guardian. “[The researchers] have found some tantalizing new information, but it’s far from spot on when it comes to knowing definitively what this strange thing is.