South America is awash in small cat species. There’s the Andean mountain cat living at high elevations. And the relatively abundant ocelot, with a range stretching into the United States. Or the kodkod, the smallest cat of the Americas, tucked away in Chile. Nearly all of these small cats belong to the Leopardus genus, of which there’s seven recognized species living in South America.
Eduardo Eizirik of Pontifícia Universidade Católica do Rio Grande do Sul in Brazil and colleagues were studying three Leopardus species from Brazil:
- L. tigrinus, the oncilla — one of the smallest cats at only 1.8 to 3.5 kilograms, with a light brown- or ochre-colored coat covered in dark brown or black spots and splotches called rosettes;
- L. geoffroyi, Geoffroy’s cat — a larger cat, about the size of a domestic kitty, with a brownish-yellow or grey coat covered in small black spots; and
- L. colocolo, the pampas cat — a small but heavyset cat with a short tail, pointed ears, long hair and stripes on its legs.
The research team had been investigating the relationships between the three cat species and found evidence that some of the cats may have been interbreeding. So they decided to take a closer look by examining markers in the DNA of 27 pampas cats, 74 Geoffroy’s cats and 115 oncillas, including individuals from northeastern Brazil, an area the researchers hadn’t been able to sample in previous studies.
The kitties’ DNA revealed a complex story of speciation and hybridization. Instead of three species, there are actually four. According to the DNA analysis, the oncilla is really two species, L. tigrinus in the northeast and the newly named L. guttulus in the south. The two species don’t interbreed and they prefer different habitats. L. tigrinus can be found in savannas and dry shrubland and forests, whereas L. guttulus lives in wet, dense Atlantic forests. The two species look very similar, though there appears to be a trend for L. tigrinus individuals to have lighter coats and smaller rosette spots.
The discovery that the oncilla is actually two species comes 50 years after German zoologist Paul Leyhausen suggested that there might be more than one species of this cat. He noted that there appeared to be some differences in morphology and behavior. Plus, attempts to get individuals that probably represented the two different species to interbreed failed. But no one ever followed up on those observations until now.
The two species of oncilla may be distinct, but the DNA studies found that the lines between some of the others may be less so. The researchers found evidence that in the past L. tigrinus individuals must have interbred with pampas cats. And where the range of L. guttulus overlaps with that of the Geoffroy’s cat, those two species still interbreed, creating hybrids.
All four species of kitties are threatened, the researchers note. And the discovery of a new species hiding in plain sight reminds us about the continued need to learn more about the world around us. We can’t do anything to prevent a species from disappearing if we don’t even know it existed in the first place.