Researchers tagging marine animals off Australia’s Orpheus Island were shocked when a tiger shark they caught spat up an echidna, a grub-eating monotreme recognizable for its spine-covered body. Known for eating just about anything, it seems this tiger shark met its match.

“I’ve seen videos of them eating a rock for no reason,” said Nicolas Lubitz, a former PhD student at James Cook University and who spearheaded the tagging trip, in a university release. “In this case, I think the echidna must have just felt a bit funny in its throat.”

Lubitz only managed to get one photo, which you can see above. The shark is obviously the grey mass at left. The echidna is a bit harder to see: It’s the darkish blob in the center-bottom of the image. But there’s a photo of an echidna below for your convenience, to better understand what this shark attempted to digest. In short, it’s not the kind of animal you’d like to swallow whole. A scallop, sure. An egg—if boiled first—maybe. But a spike-covered creature that can grow to nearly two feet (61 centimeters) long? I’m loath to stoop to a lazy pun, but that’s hard to swallow.

Echidnas are known to swim in shallow waters between islands, Lubitz said, which is probably how it got caught by the predatory shark. The echidna would’ve appeared as a tasty morsel to an open-minded eater that can grow up to 18 feet long (5.5 meters) and 2,000 pounds (nearly a ton). The shark the team caught was just about 10 feet (3 meters) long. According to The Ocean Conservancy, tiger sharks eat “practically anything they can get their jaws around” and have been found with license plates, tires, and other sharks in their stomachs. If only those other sharks were echidna-shaped…maybe they would have stood a chance.

The echidna regurgitated by the shark was dead. Though the release did not specify a cause of death, it noted the echidna was fully intact, indicating the shark swallowed it whole. Surprisingly, the shark itself was not harmed by the disagreeable foodstuff, and swam away after the team fitted it with an acoustic tracker.

Another tiger shark tagged by the team spat up half a dugong. Hats off to these sharks—they’re not afraid to try new foods. But if they wanted to be a bit more polite they wouldn’t spit up the stuff they don’t like, and certainly not in front of company.

More: A Single Orca Killed and Ate a Great White Shark, Video Reveals