A new genus and species of acanthomorph teleost, Spinocaudichthys oumtkoutensis, gen. et sp. nov., is described from the Cretaceous (Cenomanian) of Morocco. This taxon is the first Cretaceous acanthomorph ever recorded from a freshwater deposit. Its caudal fin displays dorsal and ventral procurrent spines, a feature only present in some acanthopterygian fishes. It also shares features with paracanthopterygians. However, this fish cannot be a holacanthopterygian (sensu Johnson and Patterson, 1993) because it lacks a pelvic spine and has a plesiomorphic caudal skeleton. Here, we consider it as an acanthomorph incertae sedis and we discuss relationships of the Acanthomorpha.