Electric ‘knife’-like creature found in river of Colombia. It’s a new species
In a river of central Colombia, an electric “knife”-like creature swam through the clear water and used its “tube-like snout” to look for food. Something about it caught the attention of nearby scientists — and for good reason.
It turned out to be a new species.
A team of researchers visited several tributaries of Guayabero River in 2018 as part of a project to survey aquatic ecosystems, according to a study published Sept. 26 in the peer-reviewed journal Ichthyology and Herpetology.
During the visits, researchers caught four unfamiliar-looking fish, the study said. Intrigued, they took a closer look at the animals and realized they’d discovered a new species: Sternarchorhynchus guayaberensis, or the Guayabero River knifefish.
Guayabero River knifefish have skinny, elongated bodies reaching just over 7 inches in length, the study said. They have a “tube-like snout” that curves down slightly and a “short” tail. Their scales are “sparse” and “hidden by overlying skin.”
Photos show the “bluish sheen” of the new species.
Guayabero River knifefish were found in “clear water” rivers with “sand and clay” riverbeds and “abundant trunks and tree branches,” researchers said.
Much about the new species and its lifestyle remains unknown. Generally, Sternarchorhynchus knifefish use their snouts for a “specialized type of feeding mode known as ‘grasp-suction’” that enables them to extract prey from “compacted clay, decaying wood, debris, and mud,” researchers said.
Like other related groups of fish, Sternarchorhynchus knifefish have specialized organs for sensing and emitting electricity, the study said.
Researchers said they named the new species after the Guayabero River where it was first discovered and, so far, the only place where it has been found. The discovery site is in central Colombia and roughly 150 miles south from Bogotá.
The new species was identified by its fin shape, scales, body proportions, coloring and other subtle physical features, the study said.
The research team included Luz Eneida Ochoa, Juan Gabriel Albornoz-Garzón and Carlos DoNascimiento.
This story was originally published October 3, 2025 at 3:09 PM with the headline "Electric ‘knife’-like creature found in river of Colombia. It’s a new species."
