The type material of Genyodectes serus, the first unquestionable non-avian theropod dinosaur to be described from South America, is redescribed in detail and its provenance and systematic position are discussed. Although no detailed information about the provenance of the specimen exists, it is probably derived from the lower part of the Cerro Barcino Formation (Chubut Group; Aptian-Albian) at Cañadón Grande, central Chubut Province, Argentina. Genyodectes is characterized by closely-spaced premaxillary teeth that are arranged in an overlapping en-echelon pattern and extremely transversely compressed maxillary teeth, the longest of which exceed the minimal height of the dentary in apicobasal length. Although systematic information is limited by the fragmentary nature of the material, the combination of fused interdental plates, maxillary and dentary teeth with a pronounced flat or even slightly concave area adjacent to the serrated carinae, premaxillary teeth that are considerably shorter than the maxillary teeth and strongly compressed and very long maxillary teeth indicates neoceratosaurian and, more specifically, ceratosaurid affinities for Genyodectes. Thus, this taxon adds a further lineage of neoceratosaurs to the already diverse South American record of this group.