Choneziphius Duvernoy, 1851

Bianucci, Giovanni, Miján, Ismael, Lambert, Olivier, Post, Klaas & Mateus, Octávio, 2013, Bizarre fossil beaked whales (Odontoceti, Ziphiidae) fished from the Atlantic Ocean floor off the Iberian Peninsula, Geodiversitas 35 (1), pp. 105-153 : 110

Genus Choneziphius Duvernoy, 1851

TYPE SPECIES. — Choneziphius planirostris from southern North Sea Basin, probably Late Miocene ( Lambert 2005).

OTHER SPECIES INCLUDED. — Choneziphius leidyi n. sp.

EMENDED DIAGNOSIS. — Choneziphius differs from all other ziphiid genera in the mesorostral groove dorsally closed at the level of the antorbital notches by the joined medial margins of the premaxillary sac fossae, forming a prominent ridge posteriorly shifted to the left, and separating deeply concave anterior portions of the premaxillary sac fossae.

It also differs from the other ziphiine genera in the maxilla covered at the rostrum base with prominent excrescencies. Moreover it differs from Ziphius and Izikoziphius in the medial fusion of the premaxillae dorsally closing the mesorostral groove; from Globicetus n. gen., Imocetus n. gen., and Tusciziphius in lacking an extremely ossified trapezoidal vertex with the anterior part of the nasals contacting the premaxillary crests; from Imocetus n. gen. in lacking a wide facial depression, a rostral maxillary spur-shaped crest, and in the location of the premaxillary foramen (not posterior to the level of the antorbital notch); from Globicetus n. gen. in lacking a large spherical medial premaxillary prominence at the rostrum base; from the possible ziphiine Caviziphius in shallower premaxillary sac fossae and in the more slender and lower right premaxillary crest.

DISCUSSION ffle fossil record of Choneziphius is primarily based on several partial skulls and rostra referred to the type species C. planirostris . fflese fossils have been collected in sediments of North Sea, probably dated from the late Miocene ( Belgium, Netherlands, and UK; see Lambert [2005] for bibliography and review). Lankester (1870) described C. packardi Lankester, 1870 based on an incomplete rostrum from Suffolk ( UK). Leidy (1876, 1877) described C. liops Leidy, 1876 and C. trachops Leidy, 1876 , based on fragmentary rostra that are now lost, from the Phosphate Beds of South Carolina ( USA). While reviewing the genus Choneziphius, Lambert (2005) considered C. packardi as based on too fragmentary material to allow specific or even generic determination; he considered C. liops as a possibly valid species (rostrum shorter and with anterior narrowing stronger than in C. planirostris ), and C. trachops as possibly conspecific with C. planirostris . According to Lambert (2005), Proroziphius macrops Leidy, 1876 and probably P.chonops Leidy, 1876 , both based on fragmentary and unfortunately lost skulls from the Phosphate Beds of South Carolina, should be included in the genus Choneziphius . Whitmore & Kaltenbach (2008) considered C. trachops as a valid taxon and assigned to this species a large rostrum collected from reworked sediments at the Lee Creek Mine, North Carolina.Although the above mentioned taxa show the apomorphies of the genus Choneziphius (at least on illustrations), we restrict these species, based on too fragmentary material, to their holotypes and consider them as incertae sedis.