Genome-wide data support recognition of an additional species of Neotropical river otter (Mammalia, Mustelidae, Lutrinae).

This article focuses on the population structure and taxonomic status of the Neotropical Otter (Lontra longicaudis) using genome-wide nuclear markers called ultraconserved elements (UCEs). The study analyzed 29 individuals across the species’ range and found strong genetic differentiation between trans-Andean populations (Mexico and Colombia) and cis-Andean populations (rest of South America), with the trans-Andean group forming a distinct clade that warrants recognition as a separate species, Lontra annectens. Within the cis-Andean group, further substructure was detected, supporting the distinction of Amazonian and Central–Eastern populations, roughly corresponding to previously proposed subspecies. These findings refine the taxonomy of L. longicaudis and have implications for conservation management by identifying evolutionarily significant units within this otter complex.