‘Silvery’ river creature with ‘unique’ stripe turns out to be new species
CORRECTION: This story has been updated to accurately reflect the description of the new species.
The story continues below.
In a remote river of northern Brazil, a “silvery” creature moved through the water, or at least tried to, but something caught it and pulled it to the surface.
Scientists looked at their catch. They’d just discovered a new species.
A team of researchers visited a national park in “a remote region” of Amapá, a state in northern Brazil, in 2005 to survey river life, according to a study published April 29 in the peer-reviewed journal Proceedings of the Academy of Natural Sciences of Philadelphia.
During their visit, researchers caught three “distinctive”-looking fish and, after taking a closer look, realized they’d discovered a new species: Cyphocharax ivo, or Ivo’s curimatid.
Ivo’s curimatids can reach about 2 inches in length, the study said. They have “bluntly rounded” snouts, medium-sized eyes and a “unique” stripe running down the length of their bodies.
Photos show the new species after being preserved, its “silvery” color fades to pale yellow with a “striking dark stripe” clearly visible, the study said.
Other photos show a related species of curimatid soon after being caught. It looks silvery with yellow fins and some “greenish” hues, researchers said.
Little is known about the lifestyle of Ivo’s curimatids. They are “potentially rare” and, like other curimatid fish, probably “feed on detritus and organic matter,” the study said.
Researchers said they named the new species after Ivo Silva dos Santos, a “technical assistant in the Ichthyology Laboratory of the Instituto de Pesquisas Científcas e Tecnológicas do Amapá,” because of “his brilliant fieldwork and help developing projects related to the fishes of Amapá state, Brazil.”
So far, Ivo’s curimatids have only been found in a river of Amapá state in northern Brazil and near the border with French Guiana and Suriname.
The new species was identified by its coloring and other subtle physical features, the study said. Researchers did not provide a DNA analysis of the new species.
The research team included Bruno Melo, Cecile Gama and Mark Sabaj.
This story was originally published May 5, 2025 at 11:52 AM with the headline "‘Silvery’ river creature with ‘unique’ stripe turns out to be new species."
