‘Bright yellow’ forest creature with ‘powerful’ call discovered as new species
As darkness seeped into a forest in South America, a “bright yellow” creature with “large” eyes perched on the leaves and began calling. The “powerful” sound caught the attention of nearby scientists — and for good reason.
Its source turned out to be a new species.
A team of researchers spent 20 years doing “extensive field work” in French Guiana, an overseas territory of France along the northeastern coast of South America, “in an effort to better understand the extraordinary diversity of this region,” according to a study published July 28 in the peer-reviewed European Journal of Taxonomy.
During some of these wildlife surveys, researchers encountered a few “cryptic”-looking frogs, the study said. At first, researchers identified these frogs as a known species, but years later, they decided to take a closer look.
The team analyzed the frogs’ DNA, examined their appearances and noticed several subtly yet consistently unique features, the study said. Researchers realized they’d discovered a new species: Pristimantis flavus, or the yellow rain frog.
Yellow rain frogs can reach about an inch in length, the study said. They have “large,” “copper”-colored eyes, and fingers with “expanded” discs.
Researchers said they named the new species after the Latin word for “yellow” because of its “vivid” appearance.
Photos show the color variation of the new species, which changes “depending on light and/or temperature conditions.” The frogs “are paler at night than during the day” but still retain “a distinct dark brown” line between their eyes, the study said.
Male yellow rain frogs make a “short and powerful ‘tk’ sounds, similar to tongue clicks,” researchers said. “Males were found calling in chorus, typically calling for about one minute … They then remain silent for another minute before starting to call again,” a cycle heard “throughout the night.”
The new species is nocturnal and tree-dwelling, but much about the lifestyle and behavior of the new species remains “unknown,” the study said. No female yellow rain frogs were found.
In general, rain frogs are “difficult” to study because “many of them” are “only found in the forest canopy,” the study said. This “peculiar ecology makes them difficult to observe and collect,” especially female frogs, which don’t call like male frogs do.
So far, the new species has only been found at two sites within a disputed territory, controlled by French Guiana but claimed by Suriname, the study said. French Guiana also borders Brazil.
The research team included Alexander Tamanini Mônico, Elodie Courtois, Esteban Diego Koch, Michel Blanc, Maël Dewynter and Philippe Kok.
The team also discovered a second new species of rain frog.
This story was originally published July 30, 2025 at 6:38 AM with the headline "‘Bright yellow’ forest creature with ‘powerful’ call discovered as new species."
