Bolivian ‘weird cat’ becomes first new cat species discovered in 100 years

A wild cat found in Bolivia nearly a decade ago has been identified as a previously unknown species, making it the first new member of the cat family to be discovered in more than a century, according to a study published in Current Biology.

The discovery began in 2016 when biologist and National Geographic Explorer Paola Nogales-Ascarrunz received a call from a wildlife sanctuary about what staff described as a “weird cat”.

A local man had found the animal as a kitten on a road near a forest and taken it home, believing it was a domestic breed. After living with the animal for about a year, however, he realised it was a wild cat and took it to the Senda Verde wildlife sanctuary on the subtropical eastern slopes of the Bolivian Andes.

Nogales-Ascarrunz, founder and lead scientist of the Bolivian Felids Research Program, was immediately intrigued. The animal had a small, compact face, short rounded ears, long whiskers and leopard-like spots. It was also noticeably smaller than a typical house cat.

“I took a hundred pictures of it,” Nogales-Ascarrunz recalled. “I was so fascinated.”

At the time, she believed the animal was a tiger cat belonging to the species Leopardus tigrinus. Known by names including tigrina, oncilla, tigrillo and little spotted cat, the species was first described in 1775 and was long thought to range across parts of Central and South America.

But in 2019, while preparing a booklet on Bolivia’s wild cats, Nogales-Ascarrunz noticed something unusual. The rosettes on the animal she had photographed were considerably larger than those shown in a reference photograph of tiger cats from neighbouring Brazil.

“This is so wrong,” she thought.

It took several more years for her to develop the genetic-analysis expertise needed to investigate the mystery. Working with geneticist Eduardo Eizirik of Pontifical Catholic University of Rio Grande do Sul in Brazil and study co-lead author Jonas Lescroart of the University of Antwerp, she compared the animal’s genome with those of other cats in the Leopardus genus.

The analysis revealed that the Bolivian cat represented a distinct evolutionary lineage. In their study, the researchers propose naming it Leopardus tilcayo, after the name used for the animal by local people.

When researchers asked why they called it “tilcayo”, locals had no specific explanation. “My grandpa called it tilcayo, so I call it tilcayo,” Nogales-Ascarrunz said.

Scientists currently know that L. tilcayo inhabits Bolivia’s Yungas forest ecoregion, which stretches along the eastern slopes of the Andes. Much about the species, however, remains unknown, including what it eats, what predators threaten it and how it reproduces.

“So many basic things are not known,” said Nogales-Ascarrunz, who is a co-lead author of the study.

Genomes redraw the cat family tree

The discovery is significant not only because it adds another species to the cat family but also because it changes scientists’ understanding of the evolution of small wild cats.

Researchers analysed complete genomes from 38 individuals across the Leopardus genus. Their findings showed that L. tilcayo diverged from other tiger cats about 1.4 million years ago, an evolutionary separation comparable to that between modern lions and extinct cave lions.

Scientists had already begun uncovering hidden diversity among tiger cats. Research published in 2013 found evidence that what was then considered Leopardus tigrinus actually comprised two distinct species. In 2024, researchers proposed another genetically distinct species.

The latest study brings the number of recognised tiger cat species to five.

“What we once thought to be a single species, we’ve started to see that it was actually a species complex,” said Eizirik.

Small wild cats have historically received less scientific attention than larger species such as lions, tigers and leopards. Their elusive behaviour also makes them difficult to study, and physical appearance alone can sometimes be misleading.

One museum specimen included in the research, for example, had previously been identified as a margay before scientists later determined it was a tiger cat based partly on the direction of the hairs on its neck.

Genomic analysis can reveal evolutionary differences that photographs and field observations cannot easily detect.

James Sanderson, founder and director of the Small Wild Cat Conservation Foundation and a member of the IUCN Cat Specialist Group, who was not involved in the study, said the findings could significantly change how specialists classify small cats in the Leopardus genus.

The study also provides evidence for a proposed tiger cat subspecies in Peru, Leopardus tigrinus antisuyo. Sanderson said the findings could also indicate that margays, long considered a single species ranging from Mexico to Argentina, may comprise several distinct species. Eizirik said a more focused genetic study would be needed to establish that.

Discovery could reshape conservation

The identification of new species can have direct consequences for conservation because populations that were previously grouped together may need to be assessed separately.

“If you think [the tiger cat] is a single thing from southern Brazil all the way to Costa Rica, you’re going to find it’s not endangered,” Eizirik said. “But if we find that it’s not a single thing, but actually five things, each of them must be assessed separately.”

Scientists do not yet know how many L. tilcayo individuals remain in the wild.

Sanderson said separating one recognised species into several can make each individual population smaller in conservation terms, potentially increasing the urgency of protecting them depending on their population sizes and distribution.

Researchers also believe the genomic methods used in the study could lead to further discoveries among small wild cats in other parts of the world.

Sanderson said similar work could reveal previously unrecognised species in Africa and Asia.

For Nogales-Ascarrunz, the discovery is ultimately a reminder of how much remains unknown about the natural world.

“Our world is extremely complex,” she said. “Sometimes we think that most of it is known, that there's not a whole lot to discover, but in fact, it's the other way around.”

Even among the world’s best-known mammals, she said, species remain hidden in plain sight.

“Even in the cats, there are things out there that are undescribed, things that people haven't found yet,” Nogales-Ascarrunz said. “So let's go out and find them and protect them.”