Scientists Photograph 27 Newly-Discovered Species Including ‘Blob-Headed Fish’

A fish with a broad, flathead and a fin sticking up on its back lies on a rock surface, surrounded by patches of moss. The fish has a textured skin and a mottled brown-grey appearance.
This ‘blob-headed’ fish was a shocking discovery due to its enlarged blob-like head, a feature that the fish experts have never seen before. The function of this unusual structure remains a mystery. | Conservation International/photo by Robinson Olivera

Researchers discovered 27 animal species new to science on an expedition in Peru including a “blob-headed fish” and a type of semi-aquatic mouse.

The new species were discovered during an expedition conducted by scientists from the environmental non-profit Conservation International and members of local indigenous groups to Alto Mayo landscape of northwestern Peru, which includes the Amazon rainforest.

The 38-day expedition covered about 1.9 million acres of forest and agricultural areas containing a diverse range of ecosystems.

However, the researchers were not expecting to unearth so many species new to science. By the end of their 38-day expedition through the Alto Mayo landscape, they had uncovered 27 never-before-seen species including four mammals, eight fish, three amphibians, and 10 butterfly species.

Close-up of a bamboo rat on a forest floor, standing on a piece of wood. The rodent has a dark, coarse fur coat, prominent whiskers, and small eyes. Fallen leaves and natural debris surround the animal, suggesting a forest or woodland setting.
A semi-aquatic (amphibious) mouse that is new to science. Credit: Conservation International/photo by Ronald Diaz
A small rodent sits on a branch with green leaves in the foreground. The night sky is visible in the background with the moon surrounded by a prominent halo effect.
This arboreal opossum species is very small but has large ears with excellent hearing. It is active at night and can be seen here under a full moon. Opossums are a type of marsupial, most of which carry their young in a pouch. Credit: Conservation International/ photo by Marlon Dag

Conservation International says another 48 other new species may also have been found, but further study will be needed to determine whether they are new to science.

One of the most remarkable discoveries was an amphibious mouse with partially webbed feet, adapted for life in the water. It belongs to a rare group of semi-aquatic rodents, among the world’s most elusive, with only a few known species ever observed by scientists.

The other new mammals the team discovered were a spiny mouse, a short-tailed fruit bat, and a dwarf squirrel.

A squirrel with a bushy tail is perched on a mossy rock against a dark background, showcasing its textured fur and alert posture.
This dwarf squirrel species is a very small squirrel that is difficult to spot in the rain forest where it runs swiftly and nimbly jumps and hides among tree branches. This species is new to science and will also belong to a new genus —a higher level of distinction than simply being a new species. Credit: Conservation International/ photo by Ronald Diaz
A small brown salamander with shiny eyes is resting on a large green leaf. Its body is slightly curved, and it has a slender tail. The texture of the leaf is visible, providing a natural backdrop.
A new species of salamander which spends most of its time in low vegetation and shrubs. Credit: Trond Larsen
A close-up of a bat with brown fur and large ears against a dark background. The bat's eyes are open, and its nose and facial features are prominently visible. Small debris or seeds are scattered on its fur.
One of the 45 bat species documented on the expedition. Credit: Conservation International/ photo by MarlonDag

Also described for the first time was the “blob-headed” fish, which gets its name from its enlarged, blob-like head. Fish experts involved with the survey had never seen a feature like this before.

“The blob-headed fish has an incredibly bizarre head that looks almost like a giant swollen nose,” Trond Larsen, who leads Conservation International’s Rapid Assessment Program in the Moore Center for Science, tells CNN. “Scientists have never seen anything like it, and we don’t know what the function of this bizarre blob-like structure is.”

The scientists have theorized that that the blob helps the animal detect food, but it still “remains a mystery.”

Conservation International’s expedition was carried out in 2022. However, the team only revealed the results in a study published in December.

“Discovering four new mammals in any expedition is surprising – finding them in a region with significant human populations is extraordinary,” Larsensays in a news release.

“This is a vibrant, dynamic mosaic of ecosystems, both natural and anthropogenic, that we must maintain and restore if we hope to protect the species found there.”


Image credits: All photos by Conservation International.
 

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