Mysterious new species of blind 'unicorn fish' discovered in China

Guizhou Normal University and Zhejiang Forest Resource Monitoring Center discover the new species in the Guizhou Province a cave

by Lorenzo Ciotti
Mysterious new species of blind 'unicorn fish' discovered in China
© Xu/ZooKeys

A new species of cave fish has been discovered in China, which has a peculiarity that distinguishes it from all its others. This is a structure or bump found on the forehead. For this reason it has been nicknamed by everyone as unicorn fish.

Scientists have taxonomized it as Sinocyclocheilus longicornus, it was discovered in a dark cave in the Pearl River, Hongguo City, Guizhou Province. Guizhou Normal University, who collaborated with Zhejiang Forest Resource Monitoring Center, Fishery Administration of Qiubei County and Guiyang Healthcare Vocational University, made the discovery and described the new species.

The blind unicorn fish discovered in China

Sinocyclocheilus are freshwater species endemic to three Chinese provinces: Guangxi, Yunnan and the aforementioned Guizhou. They live only in caves or environments closely associated with them.

They are troglobitic animals, that is, they have evolved specific adaptations for an extreme and dark environment such as the underground one. The researchers, coordinated by professors Jiang Zhou and Cheng Xu, collected around thirty specimens during an expedition to study cave fish.

From genetic and morphological analyzes it emerged that fifteen of them belonged to a completely new species, characterized by the presence of horn. The Sinocyclocheilus longicornus is distinguished by the absence of pigmentation, with degenerate eyes that allow limited vision, peculiar to the rays of the fins.

In these perpetually dark environments it is evolutionarily disadvantageous to spend energy on sight and on producing and maintaining bright colours. As for the horn, according to scholars this anatomical structure could have a meaning in relation to life in an environment constantly immersed in darkness.

According the research published on Zoo Key, the scientists told: "The specific epithet longicornus is an invariable noun in apposition, derived from the Latin words longus, meaning long, and cornu or cornus, meaning horn of the forehead, in reference to the presence of a long horn-like structure on the forehead of the species.

We propose the English common name Long-Horned Golden-lined Fish and the Chinese common name Cháng Jiǎo Jīn Xiàn Bā."