The Estuarine sea catfish (Cathorops aguadulce), also known as the Aguadulce sea catfish, is a species of sea catfish in the family Ariidae. It was described by Seth Eugene Meek in 1904, originally under the genus Galeichthys. It is a tropical fish which is known from Mexico to Guatemala, where it typically inhabits freshwater rivers, lagoons, and drainages, also sometimes dwelling in marine waters. It reaches a maximum standard length of 22.7 cm (8.9 in).