Crabs are already among the freakiest-looking animals we encounter, so it's no surprise that their ancestors were bizarre, too.
In a study published Wednesday, scientists announced the discovery of a strange, 95-million-year-old species that will force paleontologists to rethink the definition of a crab: It may actually be a new branch on the crustacean tree of life – not unlike a platypus of the crab world, explained study lead author Javier Luque of Yale University.
"This new discovery is one of the most exciting fossil findings in the tropics in the past decade," he said in a statement.
Luque first discovered a fossil of the crab in Colombia in 2005. Several other specimens have since been discovered in far-flung spots from Wyoming to Morocco, Live Science reported.
The weird creature was about the size of a quarter, with large compound eyes with no sockets, bent claws, leg-like mouth parts, an exposed tail and a long body.
This newly discovered critter — named Callichimaera perplexa, which means "perplexing beautiful chimera" — had a hodgepodge of body parts, Live Science said. That name references the mythical chimera from Greek mythology, which had a lion's head, a goat's body and a snake's tail.
"It hints at how novel forms evolve and become so disparate through time," according to Luque. "Usually we think of crabs as big animals with broad carapaces, strong claws, small eyes in long eyestalks, and a small tail tucked under the body. Well, Callichimaera defies all of these 'crabby' features and forces a re-think of our definition of what makes a crab a crab."
It's the earliest example of a swimming arthropod with paddlelike legs since the extinction of sea scorpions more than 250 million years ago, according to the study.
"This discovery, from the mid-Cretaceous, illustrates that there are still surprising discoveries of more recent, weird organisms waiting to be found, especially in the tropics," Luque said. "It makes you wonder 'what else is out there for us to discover?'"
The study was published in the peer-reviewed journal Science Advances, a publication of the American Association for the Advancement of Science.
This article originally appeared on USA TODAY: Weird prehistoric creature was 'strangest crab that ever lived,' with a 'hodgepodge of body parts'