Locals find ‘blunt’-headed river creature near cave in China. It’s a new species
Near the entrance of a cave in southern China, a “blunt”-headed creature swam through the clear water. Its “small” eyes scanned the rocky riverbed looking for something to munch, but it wasn’t the only one looking around.
Locals noticed the “elongated” animal — and discovered a new species.
A team of scientists visited Yunnan Province in 2023 and 2024 to survey subterranean aquatic life, according to a study published Aug. 26 in the peer-reviewed journal Zoosystematics and Evolution.
During their surveys, locals from Dehou Town showed researchers some unfamiliar-looking loach fish, the study said. Intrigued, they visited the cave where the fish were found and caught several more.
Researchers took a closer look at the fish, analyzed their DNA and realized they’d discovered a new species: Balitora dehouensis, or the Dehou heterocercal stone loach.
Dehou heterocercal stone loaches are considered “medium-sized,” reaching about 2.5 inches in length, the study said. They have “elongated” bodies with “large” fins. Their “blunt” heads have “small” eyes and “prominent” whisker-like barbels.
Dehou heterocercal stone loaches varied in coloring depending on whether the fish came from inside or outside of the cave, researchers said and photos show. The above-ground fish were “greyish brown” with several “saddle shaped dark blotches” on their backs, while the “subterranean” fish were “uniformly creamy yellow.”
The new species lives in “torrential stretches of river with clear, well-oxygenated water as well as boulder and gravel” surfaces, the study said. “Enlarged and flattened paired fins enable it to resist the current and adhere to the rocky surface while feeding on algae and aquatic invertebrates.”
Around the cave, researchers observed “a dramatic seasonal change of subterranean water level.” In the wet season, “subterranean water levels rise” and create an “ideal” environment for Dehou heterocercal stone loaches outside the cave. In the dry season, water levels drop and the new species “retreats into the cave.”
The new species’s common name refers to the “bizarre” shape of the base of its tail fin, the study said. A photo shows how the top and bottom of the fish’s tail base are uneven, forming a diagonal line. This tail shape is scientifically referred to as “heterocercal.”
Researchers concluded “the uniquely derived (tail) fin shape of B. dehouensis might be adaptations for (its) constantly changing environment.”
The new species’s scientific name refers to Dehou, the town where it was first discovered and, so far, the only place where it has been found, researchers said. Dehou is in Yunnan Province of southern China and near the border with Vietnam.
Dehou heterocercal stone loaches were identified by their DNA, fin shape, barbels, size and other subtle physical features, the study said.
The research team included Hao-Tian Lei, Xin-Rui Pu, Hong-Fu Yang, Ming-Xin Zhu, Hao-Lin Mo, Xiao-Yu Liu, Mo Wang and Bao-Liang Bi.
This story was originally published August 26, 2025 at 12:58 PM with the headline "Locals find ‘blunt’-headed river creature near cave in China. It’s a new species."
