Large river predator — weighing up to 220 pounds — discovered as new species
In a river of southern China, a large predator with “thick” skin rested on the riverbed and waited for its next meal. Its “small” eyes scanned its surroundings, but it wasn’t the only one looking around.
Visiting scientists noticed the bottom-dwelling animal — and discovered a new species.
A team of researchers visited several rivers in Yunnan province between 2004 and 2024 as part of a project to survey aquatic wildlife, according to a study published June 24 in the peer-reviewed journal Zoosystematics and Evolution.
Over the years, the team found just over a dozen large and “cryptic”-looking catfish, the study said. At first, they thought the fish were a known and fairly widespread species, but when they took a closer look, they noticed some subtle but consistent differences.
Researchers realized they’d discovered a new species: Bagarius protos, or the protos catfish.
Protos catfish are considered “large,” the study said. The fish caught by scientists reached about 19 inches in length, but locals reported larger fish weighing up to or “over” 220 pounds.
Photos show the new species. Its head is “wide” with a “long” snout and “small” eyes, researchers said. Its skin is “thick” and hardened with bumps “of various sizes.”
Overall, protos catfish are pale yellow with gray dots covering their bodies and a few gray band-like markings, a photo shows.
Like other Bagarius catfish, the new species is a bottom-dwelling predator, the study said. It “used to be a local high-value food fish” and was caught by baiting a “thick nylon rope as a line, tying one end to a boulder, and harvesting (the fish) on the next day.”
Much about the lifestyle and behavior of protos catfish remains unknown.
Researchers said they named the new species after the Greek word for “original” because it has “the most primitive position” on the evolutionary tree of Bagarius catfishes.
So far, protos catfishes have been found in several rivers of Yunnan province, a region of southern China bordering Laos, Myanmar and Vietnam, the study said. Researchers expect the new species also occurs in Myanmar and Thailand.
The new species was identified by its eye size, head shape, fin shape, skeleton, coloring and other subtle physical features, the study said. DNA analysis found the new species had at least 8% genetic divergence from related catfish species.
The research team included Yu-Yang Zeng, Xin-Rui Pu, Hao-Tian Lei, Thaung Naing Oo and Xiao-Yong Chen.
The team also discovered a second new species of Bagarius catfish in Myanmar.
This story was originally published June 24, 2025 at 2:15 PM with the headline "Large river predator — weighing up to 220 pounds — discovered as new species."
