Creagrutus cerritulus can be easily distinguished from all congeners by the following unique characters: mouth distinctly ventrally positioned; dentary and premaxilla dentition strongly spatulate with the central and adjacent cusps of similar size; anterior portion of the dentary strongly bent forming a nearly 120° angle relative to the posterior portion of the lower jaw and resulting in the cutting edges of the dentary teeth running parallel to the distal axis of the jaw; symphyseal interdigitations present on the lingual surface between the contralateral premaxillae; a notch along the posterior margin of the maxilla present which serves for the insertion of the ligamentum primordiale; distal tips of the mesethmoid wings anteriorly bent; very tight association between the posterior, cuneiform process of the vomer and the anterior portion of the parasphenoid; intestine distinctly elongated; size of stomach reduced; and swimbladder reduced, especially the posterior chamber (Ref. 116020).