Ophionephthys limicola Lütken, 1869 (Amphiuridae) is recorded for the first time from the mainland Caribbean coast of Colombia. Although its presence was already known from the island of San Andrés, Colombia, we extend this species’ geographic range south to the Gulf of Morrosquillo. Based on 10 specimens collected between 2023 and 2024, its external diagnostic characteristics and, for the first time, its microstructures are documented. Finally, we provide an ontogenetic characterisation, focusing on external morphological traits that show significant variation.