Vicious-Looking "Alien" Fish Defies Classification

Researchers have compared the mouth of Kryptoglanis shajii to the jaws of H.R. Giger's xenomorphs, and with good reason: K. shajii is technically a catfish, but scientists say the bones of its face are so alien that they've "had a hard time fitting it into the family tree of catfishes."

Photo Credit: Mark L. Riccio, Cornell University BRC CT Imaging Facility

K. Shajii is one weird fish. It's tiny, lives underground, and is only found one place on Earth: the Western Ghats mountain range in Kerala, India. At first glance, it looks like a very small catfish. But beneath its skin is a bone structure that has confused ichthyologists for years.

For one thing, the K. Shajii is missing several structures commonly found in other species. But the results of an investigation led by Drexel University ichthyologist John Lundberg, published in the Proceedings of the Academy of Natural Sciences of Philadelphia, reveal something even more surprising. LiveScience's Elizabeth Palermo summarizes:

[Lundberg] and his colleagues used digital radiography and high-definition CAT scans to study Kryptoglanis' bone structure, finding... that the shapes of some of Kryptoglanis' bones were utterly unique among fishes of any species.

Numerous individual bones in the catfish's face are modified, giving it a compressed front end with a jutting lower jaw — similar to a bulldog's snout. The tiny fish also possesses four rows of conical, sharp-tipped teeth, the researchers said.

"The more we looked at the skeleton, the stranger it got," said Lundberg in a statement. In bulldogs, he says, the unique structure of bones in the face were the clear result of selective breeding. But "in Kryptoglanis," he says, "we don't know yet what in their natural evolution would have led to this modified shape."

[PANSP via LiveScience]