South American Tiger Cat Species Complex Revised into Five Species, with a New Felid Hidden in the Forests of Bolivia
South America is home to a group of small, spotted and rosetted cats in the genus Leopardus whose taxonomy has puzzled researchers for decades. These cats are remarkably similar in appearance, with differences among populations often limited to subtle variations in body proportions, coat color, and marking patterns. The northern tiger cat (Leopardus tigrinus) has been particularly difficult to classify. The species was named as early as 1775, yet its original description was based solely on an illustration of an animal from Cayenne, French Guiana. More than two centuries later, genetic data from the population inhabiting its type locality were still lacking.
Populations historically grouped under the general name "tiger cats" occur across a wide range of South American environments, including the Atlantic Forest, the Caatinga and Cerrado of Brazil, Andean cloud forests, the Guiana Highlands, and the Yungas forests of Peru and Bolivia. The southern tiger cat (Leopardus guttulus) has been widely accepted as a distinct species, whereas the status of the eastern tiger cat (Leopardus emiliae) and clouded tiger cat (Leopardus pardinoides) has long been debated, with different classifications treating them either as separate species or as taxa within L. tigrinus. These are the closely related tiger cats that have repeatedly been split and lumped within the broader L. tigrinus complex. Other Leopardus species, including the margay (Leopardus wiedii), Geoffroy's cat (Leopardus geoffroyi), ocelot (Leopardus pardalis), Andean cat (Leopardus jacobita), kodkod (Leopardus guigna), and pampas cat (Leopardus colocola), fall outside this particular taxonomic controversy and are not discussed further here.
A recent study analyzed whole-genome data from 38 Leopardus individuals, eight of which came from historical museum specimens. To recover DNA from these older specimens, the researchers collected small amounts of tissue from sources in which DNA tends to be better preserved, including the petrous bone inside the skull, tooth roots, skin, and tail vertebrae. DNA extracted from these materials was then sequenced to obtain genomic data from the specimens.
The researchers first compared large numbers of genetic variants across the whole genomes of different individuals. They used principal component analysis (PCA), examination of ancestry proportions, and a genome-wide neighbor-joining (NJ) tree to determine which individuals were genetically most closely related. These analyses consistently identified clearly differentiated evolutionary lineages within the disputed tiger cat populations, with each group forming its own monophyletic clade in the phylogeny.
The researchers then focused on samples with higher sequencing depth. Their genomes were divided into 22,873 non-overlapping genomic fragments, each 100 kb long, and a separate phylogenetic tree was inferred for every fragment. This produced a total of 22,873 local phylogenetic trees. By comparing and integrating these trees, the researchers could examine relationships among tiger cat lineages while also assessing whether different regions of the genome recorded the same evolutionary history.
The populations that had historically been disputed within the broader L. tigrinus complex were ultimately organized into five species: the northern tiger cat (L. tigrinus), southern tiger cat (L. guttulus), eastern tiger cat (L. emiliae), clouded tiger cat (L. pardinoides), and a newly described species, the tilcayo (Leopardus tilcayo). The northern tiger cat itself was divided into two subspecies: the nominotypical Guiana tiger cat (Leopardus tigrinus tigrinus) of the Guiana Shield and the newly described Antisuyo tiger cat (Leopardus tigrinus antisuyo) from the Peruvian Yungas. The researchers compared the genomic lineages with previously published morphological, ecological, and biogeographic evidence. The resulting taxonomic revision therefore integrated genomic evidence with existing information on morphology and geographic distribution, rather than defining species solely from a single phylogenetic tree.
The discovery of the tilcayo was somewhat unexpected. The researchers had initially anticipated that tiger cats from the Bolivian Yungas would cluster phylogenetically with clouded tiger cats from the northern Andes. Genome-wide analyses instead placed the Bolivian samples in a distinct lineage of their own. The study estimated that this lineage diverged from the lineage leading to L. tigrinus and L. pardinoides about 1.43 million years ago, during the Calabrian stage of the Pleistocene.
The holotype of the tilcayo is an adult male obtained in 2021 near the town of Arapata in the North Yungas of La Paz, Bolivia, at an elevation of approximately 1,570 m. The species name tilcayo comes from the local name used for this cat in the Bolivian Yungas. Its head-body length ranges from about 42.5 to 50.5 cm, with a tail measuring 25 to 26.5 cm. The dorsum is light brown, becoming darker along the mid-dorsal ridge, while the flanks bear relatively large and irregular dark brown to black rosettes. Compared with the clouded tiger cat, the tilcayo has shorter fur, a lower-contrast coat pattern, and lacks the broad, complete bands on the tail.
Repeated climatic fluctuations during the Early Pleistocene fragmented montane forests in the Andes and may have contributed to prolonged isolation and genetic differentiation among tiger cat populations.
Phylogenetic network analysis estimated an approximately 15% introgression signal between the tilcayo and the Antisuyo tiger cat of Peru, consistent with past gene flow between their lineages. Even more strikingly, the mitochondrial DNA of the tilcayo is more closely related to the mitochondrial lineage of Geoffroy's cat than would be expected from relationships inferred from the nuclear genome. The evolutionary history of tiger cats has involved hybridization, introgression, and incomplete lineage sorting, all of which can generate substantial mitonuclear discordance. As a result, analyses based only on mitochondrial DNA can yield evolutionary relationships that differ markedly from those recovered from genome-wide nuclear data.
This taxonomic revision also changes the scale at which tiger cat conservation must be considered. Many populations were previously grouped under the single name Leopardus tigrinus, giving the impression of one broadly distributed species. Once these populations are recognized as distinct species, the geographic range and population size of each taxon become substantially smaller. Conservation assessments conducted under a single species name may therefore fail to accurately reflect the risks faced by each evolutionary lineage. Clarifying how many species actually exist is consequently a fundamental first step toward protecting them effectively.
Author: Shui-Ye You
References
de Oliveira TG et al. (2024). Ecological modeling, biogeography, and phenotypic analyses setting the tiger cats' hyperdimensional niches reveal a new species. Scientific Reports.
Lescroart J et al. (2026). Phylogenomics and museomics reveal five distinct species of tiger cats in South America. Current Biology.
Comments