Abundant concretions at two localities in central Colombia where the San Gil Inferior and San Gil Superior formations are exposed, have yielded numerous crustacean individuals, comprising one new genus Rathbunassa n. gen.(Callianassidae), two new species Joeranina colombiana n. sp., Planocarcinus johnjagti n. sp., and three further species.The following taxa are recorded: ?Paraxiopsis sp.(Axiidae), Rathbunassa aquilae (rAtHBun, 1935) n. comb.(Callianassidae), Joeranina kerri (Luque, FeLdmAnn, SCHweitzer, JArAmiLLo & CAmeron, 2012) n. comb., Joeranina colombiana n. sp.(Palaeocorystidae), Cenomanocarcinus vanstraeleni StenzeL, 1945 (Cenomanocarcinidae), and Planocarcinus johnjagti n. sp.(Necrocarcinidae).Based on ammonite evidence, the locality within the San Gil Inferior Formation is considered to be of late Aptian age, while the one exposing the San Gil Superior Formation is of middle Albian date.Joeranina kerri is found at both localities; in contrast Planocarcinus johnjagti n. sp.occurs exclusively in the upper Aptian, while the remainder of species are all from the middle Albian locality.The taxa reported herein add important data to the palaeobiodiversity and distribution of Cretaceous decapod crustaceans.