Species Study title
There are 1,400+ species of bats in the world. This is one of them.
illustration of a bat

Nimba Myotis

New bat species discovered in the remote “sky islands” of West Africa
by Lynn Davis
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Binomial

Myotis nimbaensis
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Family

Vespertilionidae
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Colony size

Unknown
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Size

52.4–55.2 mm
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Diet

Insectivorous
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Status

Expected to be classified by IUCN as Critically Endangered
Region

The Nimba Mountains, West Africa
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Illustration: Fiona Reid
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ccording to Dr. Winifred Frick, Bat Conservation International’s (BCI’s) Chief Scientist, using harp traps to survey bat species is somewhat like trick-or-treating: You never know what you’re going to get.

Once the delicate nylon threads of the traps are installed near bat roosts, scientists wait to see which bats are caught. Dr. Frick says scientists are often like children comparing their hauls of Halloween candy. As they gently move the bats in small cloth bags to a nearby processing station where the bats are weighed and measured, DNA samples are collected, and varying species are noted, you might hear scientists quietly noting “one of these” and “three of those” before the bats are released into the night sky.

An unexpected discovery

During a night of surveying in 2018, in the high mountains of West Africa, you also might have overheard, “Wait a minute… what’s this?” followed by building excitement over the possibility of a new species discovery. The field team kept their voices quiet and controlled so they didn’t frighten the bat, but their energy was palpable as they said to one another, “Have you seen anything like this? Did you see the belly fur? What about the colors in its wings?”
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The Nimba Mountains, which rise 5,300 to 5,750 feet above sea level, encompass lowlands, a tropical forest zone, and moist woodlands. They are also home to thousands of plant and invertebrate species and an exceptional diversity of mammals.
The bat looked familiar, surely part of the genus Myotis, a group of bats with over 120 species around the world. Myotis are easily identified by several common traits including, most notably, ears that are longer than they are wide, and a long, pointed tragus. But other visual features made this bat unique. It had bright orange fur along its back, formed by tricolored hairs: black at the base, creamy white in the center, and tipped in bright oranges and coppery reds. A lighter version of tricolored hair was found on its belly, and narrow bands of orange were noted along its phalanges (the “hand-wing” that distinctly defines bat species). Its orange-and-black patterned wings seemed to shimmer.

Following the discovery, researchers studied every aspect of the bat’s physical structure, including meticulously measuring all physical attributes, including its tiny teeth, and comparing all collected information with similar species. Researchers also compiled molecular data and provided some of the world’s foremost research institutions with tissue samples to conduct gene sequencing. They compared their data to samples and specimens from the American Museum of Natural History in New York, Natural History Museum in London, Field Museum in Chicago, and Smithsonian National Museum of Natural History in Washington, D.C.

Two years later, after exhaustive research, Dr. Frick and her BCI colleagues, along with a panel of international scientists who helped document the species, published a 48-page scientific manuscript to announce the discovery of Myotis nimbaensis (meaning “from Nimba”). They summarized the discovery as “spectacular.”

West Africa’s bat diversity

In January 2018, Dr. Frick and Dr. Jon Flanders, BCI’s Director of Endangered Species Interventions, headed to the Nimba Mountains, an isolated mountain range in West Africa that intersects the countries of Guinea, Liberia, and Côte d’Ivoire. Their mission? Document the known biodiversity of the bats in the area and search for Lamotte’s roundleaf bat (Hipposideros lamottei), which is listed by the International Union for Conservation of Nature (IUCN) as Critically Endangered.
Nimba myotis
Nimba myotis
Photo: Dr. Jon Flanders
The Nimba Mountains, which rise 5,300 to 5,750 feet above sea level, encompass lowlands, a tropical forest zone, and moist woodlands. They are also home to thousands of plant and invertebrate species and an exceptional diversity of mammals.

With the discovery of Nimba myotis, BCI reports there are now more than 60 species of bats in the Nimba Mountains.

“The world still has so many places to explore, discover, and understand,” Dr. Flanders says. “Finding new species helps us better comprehend landscapes and environmental conditions because bats reflect healthy ecosystems.

“What is particularly notable,” he continues, “is that this new extremely colorful bat had not been documented in previous biodiversity surveys, indicating that the population of Myotis nimbaensis bats is very small, and one of the reasons I expect it will be classified as Critically Endangered by the IUCN.”

BCI is planning more field work in the area in 2023.

“What makes the Nimba range special is that the mountains rise from lowlands,” Dr. Frick says. “But the mountaintops have retained their biodiversity and a high number of endemics. The mountains are, for now, important ‘sky islands’ of shelter.”