A new species of the brachyuran Ophthalmoplax is documented based upon two specimens collected from shales of the Lodolitas de Aguacaliente Formation, Guadalupe Group, (Cordillera Oriental, Colombian Andes), which represents a regional transgressive event.The small crustaceans were found in the uppermost parasequences with retrogradational stacking pattern, near to the maximum flooding surface (MFS), at the end of the late Campanian Transgressive Systems Tract (TST).This is the oldest record for Ophthalmoplax in America.Morphological affinities with other species of the genus are discussed, including size reduction related with anoxia events and paleotemperature.