Scientists discover bizarre blind fish ‘with unicorn horn’ in dark Chinese cave

RESEARCHERS have uncovered a bizarre new species of fish that resembles a unicorn with a prominent horn protruding from the front of its head.

The fish, which is blind and also lacks scales or any pigmentation, was found in pitch-black cave water within China’s mountainous Guizhou province in the country’s southwest.

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The researchers dubbed the fish, which measures between 4.1 to 5.7 inches long, Sinocyclocheilus longicornus.

Details of the findings were published on January 17 in the journal ZooKeys.

According to the study, the fish has two pairs of barbels used for sensing its surrounding environment.

Most notable, however, is the fish’s horn, which has perplexed researchers, Live Science reports.

The fish’s name reflects the odd feature – longus means “long” in Latin, while cornu means “horn of the forehead.”

At the time of the discovery, researchers were studying cavefish from the genus Sinocyclocheilus, which are only found in China.

To date, there are 76 known species of Sinocyclocheilus, and they likely share characteristics with the new fish.

These may include reduced eyes, dorsal-fin rays, lateral line pores, and gill rakers.

Loss of eyesight happens because of a process known as regressive evolution, which describes when a species loses useless features over generations. 

The fish’s horn-like structure may also be shared by some related species, although it likely varies in size.

“Horns Variable or specialized morphological characters of Sinocyclocheilus are closely related to the orogeny-producing dark cave environments,” the study said.

“For example, horn-like structures (single or forked, long or short) or bulges on the back of the head, and degeneration or loss of eyes.”

Based on the study, the team of researchers hypothesizes that the evolution of the horn may have occurred in “at least two independent formations, one weakening event, and one loss event.”