River creature — with ‘intensely red’ eyes – found as new species in Brazil. See it
In the highlands of the southern Amazon rainforest, the heavy rainfall creates the headwaters of a vast river system, connecting the deepest reaches of the forest through water.
Hoping to catalog the creatures that call the rivers home, a group of researchers went on four expeditions to some of the tributaries criss-crossing the Amazon.
In the rio Tapajós basin, a small, yellow fish caught the eye of the researchers, according to a study published in the journal Neotropical Ichthyology on May 20.
It was a new species.
The fish’s body is a “yellow citrus” color, according to the study, earning its name Hyphessobrycon citrus, after “several citrus fruits.”
But the color of the body isn’t what stood out the most, researchers said.
The “upper portion of (the) eye (is) intensely red,” according to the study, “vivid” even against the yellow body.
There is also a long, black “well-defined” stripe down the side of the fish, a feature that sets it apart from other known species, researchers said.
It is about 2 inches long, but the length of the fins depends on the sex of the fish, according to the study.
The pectoral and pelvic fins on male fish are slightly larger than the female fins, and the base of the anal-fin is straight in females but convex in males, researchers said.
The fish was discovered in the “Serra do Cachimbo, in the headwaters of the rio Braço Norte,” according to the study. “ ... Despite a highly restricted distribution, the species inhabits a relatively well-preserved basin with no identifiable threats. Most of the basin where it occurs is located within protected areas.”
The Serra do Cachimbo is a mountain range in the southern region of the Pará state in Brazil, in the northern-central region of the country.
This story was originally published May 22, 2024 at 1:13 PM with the headline "River creature — with ‘intensely red’ eyes – found as new species in Brazil. See it."
