A New Species of Cat, and Only One Is Known to Exist: The Tilcayo's Warning

Hero photo: The Tilcayo tiger cat (side profile) — Alessandro Verniani, Wikimedia Commons, CC BY-SA 4.0.

01 What was announced

On Thursday, September 17, researchers publishing in Current Biology formally described Leopardus tilcayo, the Tilcayo tiger cat — a small, slender, spotted wild cat from Bolivia's Yungas cloud forest, the misty transition zone where the Andes meet the Amazon basin. It is the first newly named and described living cat species in more than a century — since the Uruguayan pampas cat in 1923.

The cat measures about 46 centimeters and weighs around 1.4 kilograms — smaller than the average house cat. It retains the name local communities have always used: “tilcayo.” The species was confirmed by complete-genome sequencing of 38 cats across eight countries, including museum specimens — and the same analysis concluded that what was considered three tiger-cat species is actually five, expanding the world's known cat family from 41 species toward 44 or more.

02 One living member — and why that is the real headline

The detail that made the discovery global news: only one confirmed member of the species is known to be alive, a female living at the Senda Verde refuge in Bolivia, where she was rescued. A second rescued cat, whose tissue was analyzed alongside hers, proved to be the same species. Scientists believe others exist — Paola Nogales-Ascarrunz of Universidad Mayor de San Andrés has heard reports of small spotted cats in the dense Yungas that were never scientifically investigated — but no others have been confirmed.

That places L. tilcayo in a strange category: a species described by science while, as far as anyone can prove, hanging on by a single individual. The researchers note the new species is missing from previous extinction-risk assessments — meaning it may be critically endangered before it has ever been assessed at all.

03 How a cat species hides for a century

The Yungas explains much of the mystery. It is steep, humid, frequently cloud-wrapped forest — some of the least accessible terrain in South America, and some of the most deforested. A 1.4-kilogram cat with spotted camouflage that hunts at night in canopy cloud does not volunteer for study.

There is also a lesson about species concepts. The Tilcayo was previously folded into the northern tiger cat, Leopardus tigrinus. The genome says its lineage diverged about 1.4 million years ago — deeper than several recognized cat species. In other words, the biodiversity was always there; the instruments to see it — whole-genome sequencing at scale — are what arrived new.

04 The conservation math, done honestly

Tiger cats as a group are considered vulnerable: deforestation, habitat loss, and illegal hunting press on all of them. The Tilcayo's cloud-forest habitat is exactly the terrain that shrinks fastest under agriculture expansion — the lower Yungas slopes are heavily converted. If the species survives in scattered low numbers across the Bolivian Yungas, its conservation status is probably endangered; if the sanctuary female is genuinely the last, the species is functionally extinct and no one has said so yet.

The honest position is that no one knows the true population. That is the discovery's operational challenge: you cannot protect a species whose range and numbers are unmeasured. The study's authors and Bolivian researchers are explicit that finding more Tilcayo — camera-trap surveys, local reporting networks, genetic sampling of rescued cats — is the immediate priority.

05 Why a small cat is a big signal

The last century without a new cat species reflected a belief: that the cat family — the most-studied, most-charismatic mammal group on Earth — was fully mapped. The Tilcayo breaks that belief with a data point: even the planet's most documented predators can still hide species-level diversity, if the habitat is dense enough and the tools are new enough.

It also lands at a moment when cloud forests are globally among the fastest-shrinking ecosystems. A species described in 2026 from a habitat under active conversion is a test case for whether discovery and protection can happen in the same decade — or whether the scientific literature and the extinction list will receive the same cat, years apart.

06 The verdict

The verified facts: Leopardus tilcayo, described in Current Biology on September 17, 2026, is the first newly named living cat species in over a century. Genome analysis of 38 cats established it and reorganized tiger cats into five species, adding a Peruvian subspecies. The only confirmed living member is a rescued female at Bolivia's Senda Verde refuge. Its lineage diverged 1.4 million years ago; it is about 46 cm and 1.4 kg; it lives in the Yungas cloud forest.

The significance: biology just told us the world's cat family is bigger than we thought — at the exact moment one of its newest members may be down to a single life. What happens next with camera traps in the Yungas will decide whether this is a discovery story or an obituary written early.