Chimuziphius coloradensis was named by Bianucci et al. (2016) [Chimuziphius differs from all other ziphiids in having the following combination of characters: mesorostral groove closed or very narrow due to the medial contact of the premaxillae; moderate thickening of the premaxillae above the mesorostral groove on the rostrum; absence of maxillary crest and rostral maxillary crest; anteroposteriorly elongated premaxillary sac fossa with premaxillary foramen distinctly anterior to the antorbital notch; ascending process of premaxilla gradually rising toward the vertex without reaching the vertical in its posterodorsal portion; absence of a transverse constriction on the ascending process of premaxilla; premaxillary crest anterolaterally directed and with reduced contact with nasal; very large triangular nasals with pointed joined anterior margin, forming an angle of ca 90
; dorsal surface of the nasals with a weak medial depression; weak transverse constriction of the frontals on the vertex; moderate elevation of the vertex of the skull (ratio between the vertical distance from the dorsal margin of the rostrum to the top of the vertex and the width of the premaxillary sac fossae = 0.77);moderate length of the temporal fossa; presence of one large infraorbital foramina on the left maxilla anterior to the base of the rostrum; and thin supraorbital process of frontal. Shares with the Messapicetus clade, Ninoziphius, and Ziphiinae: premaxillary crest anterolaterally directed and reduced contact of the premaxillary crest with the nasal. Further shares with the Messapicetus clade medial contact and moderate thickening of the premaxillae above the mesorostral groove on the rostrum. Differs from Aporotus, Beneziphius, Messapicetus, and Ziphirostrum in lacking a conspicuous prenarial basin; from Beneziphius and Choneziphius in lacking excrescences on the dorsal surface of the maxilla along the posterior half of the rostrum; from Notoziphius in having premaxillary crest more laterally directed; nasals with anterior point less ventrally bent and forming a more obtuse angle (90 vs. 75
in the latter); more anteroposteriorly elongated dorsal exposure of the supraoccipital between the maxillae; thinner supraorbital process of the frontal; and in lacking an elliptical fossa in the ascending process of premaxilla and a developed maxillary crest; from Ninoziphius in having less elevated vertex and smaller dorsal exposure of the nasals; from Ziphiinae in having shorter nasals; less elevated vertex; less concave dorsal margin of the ascending process of premaxilla in lateral view; from Berardiinae in having the premaxillary foramen distinctly anterior to the antorbital notch; supraoccipital reaching the top of the vertex; less transverse constriction of the frontal on the vertex; and in lacking a nodular protuberance formed by the interparietal or the frontals on the vertex; from Nenga, Pterocetus, Xhosacetus, and the Hyperoodontinae in lacking inclusion of the nasal in the premaxillary crest and from the Hyperoodontinae in lacking a deep anteromedial excavation of the nasals; from Nazcacetus and Tasmacetus in having less concave dorsal margin of the ascending process of premaxilla in lateral view; premaxillary foramen distinctly anterior to the antorbital notch; and weaker transverse constriction of the frontals on the vertex; from Chimuziphius in having nasals more elongated, with a more pronounced medial depression, and more pointed anterior margin; the supraoccipital being more constricted between the maxillae; and in lacking a conspicuous maxillary crest.]. Its type specimen is MUSM 2548, a partial skull (incomplete cranium lacking the anterior portion of the rostrum, most of the right side of the neurocranium, and most of the basicranium), and it is a 3D body fossil. Its type locality is Cerro Colorado (Pisco, Tortonian), which is in a Tortonian marine horizon in the Pisco Formation of Peru.