Background. Several works conducted in Mexico have addressed the Neotropical otter (Lontra longicaudis annectens), a protected subspecies (NOM-059-SEMARNAT-2010). Objectives. To know the abundance and distribution of the neotropical otter in the State of Campeche in La Lagartera Lagoon (Palizada River). Methods. During 2017 were searched the lagoon looking for indirect evidence on mangrove, collected and analyzed scats in order to identify preys. Results. Were traveled 1.49 km in each climatic season (nortes, dry, and rainy seasons), on board a small vessel, recording a total of 99 signs (85 scats, five feeding sites, five dens, and four vocalizations). We recorded the distribution of these signs across the sampling area and estimated a relative abundance of 0.30 otters/km. The analysis of 85 scats collected on logs or roots recorded six major prey groups: fish (40 %), crustaceans (26 %), reptiles (15 %), mollusks (11 %), mammals (4 %), birds (3 %) and other unidentified prey (1%). Conclusions. No evidence was found to suggest a variation in the consumption frequencies of the groups of prey by season. The presence and consumption of the "sailfin catfish" was also recorded in all seasons. The presence of four native species and five new records of prey fish was confirmed from otoliths contained in feces. This information highlights the ecological relevance of the species.