A new wildcat species that had been living in the forest of Bolivia unnoticed has been discovered, marking the first new living cat species in more than a century.
The feline, which is smaller than the average domestic cat, has been known to local communities in Bolivia's Yungas forest as the Tilcayo.
It is part of a group called tiger cats that can be found across much of South America. Its similarities to other wild cats meant it had been hiding in plain sight.
Now, DNA analysis has revealed that the animal, which measures 46 cm long and weighs 1.4 kg, is an entirely new species.
Scientists have named the new species the Tilcaya cat, or Leopardus tilcayo.
The discovery began with a 10-year-old cat nicknamed Tigrino, which lives at a rescue sanctuary in Bolivia.
Dr. Nogales-Ascarrunz was volunteering at the sanctuary when she noticed something unusual about the animal.
Tigrino had been found in the forest by a local resident who initially thought they had discovered a domestic kitten, but as the cat grew in size, it became clear it was no ordinary house pet.
Dr. Nogales-Ascarrunz had also heard reports of similar small wild cats in the dense forests of Bolivia's Yungas region, but they had never been properly investigated.
She teamed up with researchers from around the world to investigate the tiger cat family, analysing DNA from living animals and museum specimens.
Now, a new study published in Current Biology suggests there could actually be five tiger cat species rather than the three previously recognised.
Only one confirmed member of the new species is currently known, but researchers suspect others are living in the wild.
"It is impossible to protect a species if we don't know what it is or where it lives," said co-researcher Dr. Caroline Sartor of the Wildlife Conservation Research Unit at the University of Oxford.
"These are animals similar in size to a domestic cat, so you might think we would know them all by now, but this discovery shows how much biodiversity is still to be uncovered in some of the less-studied regions of the world."
There were previously 41 officially recognised living cat species, but the latest findings suggest the true number could now be 44 or higher.