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Khoikhoicetus agulhasis n. sp. HOLOTYPE. — SAM PQ 2678, partial skull including most of the rostrum, the anterior part of the cranium, and the vertex. ETYMOLOGY. — The holotype was found offshore from Cape Agulhas, a locality on the south coast of South Africa. The oceanic current running along the south-east coast of South Africa is also named Agulhas Current. TYPE LOCALITY. — No exact locality.Trawled west of Cape Agulhas, south coast of South Africa, Indian Ocean. DIAGNOSIS. — Khoikhoicetus agulhasis n. gen., n. sp. differs from all the other Hyperoodontinae in lacking the posterolaterally directed premaxillary crest. It differs from Indopacetus in: smaller size; narrow rostrum base; narrower premaxillary crests and nasals longer than the frontals on the vertex. It differs from Africanacetus n. gen., Hyperoodon, Ihlengesi n. gen., and Mesoplodon in: shorter intrusion of the nasal in the premaxillary crest; premaxillary crest not overhanging the premaxillary sac fossa. The space between the premaxillary crests is wider than in Hyperoodon and Mesoplodon. DESCRIPTION (FIGS 13; 14; TABLE 4) On the only known skull, the rostrum was probably relatively short, not much longer than the preserved length. It is somewhat wider than high along its anterior half and as wide as high posteriorly. The mesorostral groove is filled by the vomer, with a median suture on the posterior half. The ventral margin of the alveolar groove, lacking marks of alveoli, extends to the antorbital notch; contrary to Mesoplodon grayi, M. hectori, M. layardii, and M. slangkopi n. sp. (see below) this feature is not visible in dorsal view. The rostrum base lacks a prominental notch; the antorbital notch is wide and probably shallow, at the level of the premaxillary foramen and slightly anterior to the small maxillary foramen lying along the premaxilla-maxilla suture. Posterior to the antorbital notch, a low maxillary crest thickens the preorbital process, with a lateral slope similar to Africanacetus n. gen. The weakly asymmetric premaxillary sac fossae are anteromedially tilted. The ascending process is moderately constricted in anterior view. The foramina for the terminal nerve in the mesethmoid are strongly asymmetric; the left foramen is much smaller than the right. The premaxillary crest is thin and laterally elongated, with a vertical anterior surface. The posterior projection of the premaxilla along the nasal reaches the frontal. The anterolateral corner of the roughly pentagon-shaped nasals forms only a small part of the premaxillary crest; the dorsal surface is anteromedially depressed. The naso-frontal suture is anteriorly pointed; the left nasal extends longer posteriorly than the right nasal., Published as part of Bianucci, Giovanni, Lambert, Olivier & Post, Klaas, 2007, A high diversity in fossil beaked whales (Mammalia, Odontoceti, Ziphiidae) recovered by trawling from the sea floor off South Africa, pp. 561-618 in Geodiversitas 29 (4) on page 578, DOI: 10.5281/zenodo.4651080

Subfamily BERARDIINAE Moore, 1968 TYPE GENUS. — Berardius Duvernoy, 1851. OTHER GENERA INCLUDED. — Archaeoziphius Lambert & Louwye, 2006 and Microberardius n. gen. EMENDED DIAGNOSIS. — Berardiinae differ from all other Ziphiidae in the presence of a nodular protuberance formed by the interparietal or the frontals on the vertex Berardius spp. are further characterized by two pairs of apical and subapical enlarged teeth on the mandible; this character still needs to be confirmed in Archaeoziphius and Microberardius n. gen. Other characters differentiating Berardiinae from more derived taxa are mostly symplesiomorphies: narrow and thin premaxillary crest on the low vertex; supraoccipital lower than the frontals on the vertex. DISCUSSION The content of the subfamily Berardiinae as defined here is more similar to the subtribe Berardiina of Moore (1968) (only including Berardius) than to the tribe Berardiini of Muizon (1991) (including Berardius, Ninoziphius, and Tasmacetus) or to the subfamily? Berardiinae of Lambert (2005) (including Berardius and Tasmacetus). Additional specimens of Ninoziphius with a well preserved vertex could clarify the relationships of this genus in the proposed framework. A fragmentary cranium from the Neogene of Japan is referred to Berardius sp. (Takahashi et al. 1989); despite general shape similarities with Berardius, the vertex might be too incomplete to provide diagnostic characters. The presence of an ossified mesethmoid filling a significant portion of the mesorostral groove, observed in Berardius, but not verifiable in Microberardius n. gen., is also noted in SAM PQ 69676 (see below, Nenga n. gen.)., Published as part of Bianucci, Giovanni, Lambert, Olivier & Post, Klaas, 2007, A high diversity in fossil beaked whales (Mammalia, Odontoceti, Ziphiidae) recovered by trawling from the sea floor off South Africa, pp. 561-618 in Geodiversitas 29 (4) on page 565, DOI: 10.5281/zenodo.4651080, {"references":["MOORE J. C. 1968. - Relationships among the living genera of beaked whales. Fieldiana: Zoology 53 (4): 209 - 298.","LAMBERT O. & LOUWYE S. 2006. - Archaeoziphius microglenoideus, a new primitive beaked whale (Mammalia, Cetacea, Odontoceti) from the Middle Miocene of Belgium. Journal of Vertebrate Paleontology 26 (1): 182 - 191.","MUIZON C. DE 1991. - A new Ziphiidae (Cetacea) from the early Miocene of Washington State (USA) and phylogenetic analysis of the major groups of odontocetes. Bulletin du Museum national d'Histoire naturelle ser. 4, sect. C, 12 (3 - 4): 279 - 326.","LAMBERT O. 2005. - Systematics and phylogeny of the fossil beaked whales Ziphirostrum du Bus, 1868 and Choneziphius Duvernoy, 1851 (Cetacea, Odontoceti), from the Neogene of Antwerp (North of Belgium). Geodiversitas 27 (3): 443 - 497.","TAKAHASHI K., NOMURA M. & KOBAYASHI I. 1989. - A fossil cetacean skull (Berardius sp. indet.) from Dogama, Ogi-machi, Sado Island, Central Japan. Earth Science 43 (2): 102 - 105."]}

Subfamily HYPEROODONTINAE Gray, 1866 TYPE GENUS. — Hyperoodon Lacépède, 1804. OTHER GENERA INCLUDED. — Indopacetus Moore, 1968, Mesoplodon Gervais, 1850, Ihlengesi n. gen., Africanacetus n. gen., and Khoikhoicetus n. gen. EMENDED DIAGNOSIS. — Hyperoodontinae differ from all the other Ziphiidae in the deep anteromedian excavation of the nasals. DISCUSSION Hyperoodontinae as defined here follows the content of the subfamily suggested by Muizon (1991); they correspond neither to the tribe Hyperoodontini sensu Moore 1968, including Hyperoodon, Indopacetus, Mesoplodon, and Tasmacetus nor to the subtribe Hyperoodontina sensu Moore 1968, only including Hyperoodon and Mesoplodon., Published as part of Bianucci, Giovanni, Lambert, Olivier & Post, Klaas, 2007, A high diversity in fossil beaked whales (Mammalia, Odontoceti, Ziphiidae) recovered by trawling from the sea floor off South Africa, pp. 561-618 in Geodiversitas 29 (4) on page 578, DOI: 10.5281/zenodo.4651080, {"references":["MOORE J. C. 1968. - Relationships among the living genera of beaked whales. Fieldiana: Zoology 53 (4): 209 - 298.","MUIZON C. DE 1991. - A new Ziphiidae (Cetacea) from the early Miocene of Washington State (USA) and phylogenetic analysis of the major groups of odontocetes. Bulletin du Museum national d'Histoire naturelle ser. 4, sect. C, 12 (3 - 4): 279 - 326."]}

Pterocetus benguelae n. sp. HOLOTYPE. — SAM PQ 2803, partial skull including most of the rostrum, the anterior part of the cranium, and the vertex. REFERRED SPECIMENS. — SAM PQ 69684, partial skull including a part of the rostrum and anterior part of the cranium, trawled west of Cape Town, Atlantic Ocean; SAM PQ 2163, partial skull including rostrum base and anterior part of the cranium, trawled off the South African coast. ETYMOLOGY. — From Benguela Current, the oceanic current running along south-east Africa, probably since the Miocene epoch. The holotype of this species was found off the west coast of South Africa. TYPE LOCALITY. — No exact locality. Trawled south of Saldanha Bay, west coast of South Africa, Atlantic Ocean, depth of 700 m. DIAGNOSIS. — Pterocetus benguelae n. gen., n. sp. differs from all other Ziphiidae in wider and deeper antorbital notch with much anterolaterally developed preorbital process and from all other Ziphiidae, except Indopacetus and Ziphirostrum, in the premaxillary foramen positioned distinctly anterior to the level of the antorbital notch. It shares with the Hyperoodontinae, and Tasmacetus an anteromedian depression of the dorsal surface of the nasals and a strong constriction of the ascending process of the premaxilla. It differs from Hyperoodontinae in lesser dorsomedial reabsorbing of the nasals. It differs from Tasmacetus in: smaller size; less pointed rostrum with narrower rostrum base; mesorostral groove filled with vomer and a shallower alveolar groove. It further differs from Xhosacetus n. gen. in the lower maxillary crest. It differs from Ninoziphius in: elevated and narrow rostrum; mesorostral groove filled with ossified vomer and reduction of the maxillary alveoli. DESCRIPTION (FIGS 26; 27; 29A, B; TABLE 5) None of the three known specimens includes the apex of the rostrum; several centimetres are probably missing in the holotype and SAM PQ 69684. The rostrum is moderately elongated, slightly higher than wide with lateral margins parallel for most of its length. The mesorostral groove is completely filled by the vomer. A distinct median suture is visible on the vomer for the first centimetres of the rostrum base, indicating a posterior development of the bone by thickening of the lateral walls until their median contact. A shallow alveolar groove is still present without alveoli marks. The acute ventral margin of the alveolar groove extends until the antorbital notch where it ventrally limits a small basin. The premaxillary foramen is located distinctly anterior to the antorbital notch, which indicates an elongated premaxillary sac fossa, a character also present in Indopacetus. An even more anterior position of the premaxillary foramen is seen for example in Ziphius cavirostris and Ziphirostrum marginatum, but associated with a deep prenarial basin. A large circular maxillary foramen opens anterodorsally just medial to the antorbital notch. The notch is widely open and deep, because of the strong development of the preorbital process, which forms a peculiar anterolateral extension of the cranium. In anterior view, the frontal is visible in the preorbital process between maxilla and lacrimal. In anterior view, the ascending process of the premaxilla is strongly constricted ventral to the vertical, thick and wide, transversely directed premaxillary crest. On the moderately elevated vertex, the nasals are wide and pentagon-shaped. Their anterolateral corner extends only a short distance into the premaxillary crest. A vertical groove excavates the anterior margin of each nasal. The right nasal is longer posteriorly than the left. The dorsal surface of the nasals is slightly depressed anteromedially, similar to Tasmacetus. Posteriorly, the frontals are narrower than the nasals with a minimum length of 21 mm. On the vertex, the frontal is contacted by the long posterior projection of the premaxilla.

Genus Izikoziphius n. gen. TYPE SPECIES. — Izikoziphius rossi n. gen., n. sp., by present designation. OTHER SPECIES INCLUDED. — Izikoziphius angustus n. gen., n. sp. ETYMOLOGY. — Iziko is the network of South African museums, which includes the South African Museum where most of the specimens studied here are stored, Ziphius is a Recent ziphiid genus. Gender masculine. DIAGNOSIS. — Izikoziphius n. gen. differs from all the other members of the Ziphiinae in the presence of a fossa on the anterior surface of the ascending process of the premaxilla distinct from the premaxillary sac fossa. It differs from Ziphius in: longer rostrum; lack of a prenarial basin; lesser asymmetry of the premaxillary sac fossae (Tusciziphius in: the barely concave premaxillary sac fossa and the anterior part of the nasal not contacting the premaxillary crest. It differs from Choneziphius in: longer rostrum; premaxillae medially separated on the rostrum by the thickened vomer and barely concave premaxillary sac fossa. It differs from Caviziphius in: premaxillae medially separated on the rostrum by the thickened vomer; lower rostrum base and less asymmetric and barely concave premaxillary sac fossa. It differs from Aporotus, Beneziphius, Messapicetus, and Ziphirostrum in: longitudinally elongated nasals; premaxillae medially separated on the rostrum by the thickened vomer and lack of a constriction of the ascending process of the premaxilla (last character less clearly present in Messapicetus). Both species of Izikoziphius n. gen. have a somewhat smaller cranium size than Ziphius cavirostris., Published as part of Bianucci, Giovanni, Lambert, Olivier & Post, Klaas, 2007, A high diversity in fossil beaked whales (Mammalia, Odontoceti, Ziphiidae) recovered by trawling from the sea floor off South Africa, pp. 561-618 in Geodiversitas 29 (4) on page 570, DOI: 10.5281/zenodo.4651080

Genus Microberardius n. gen. TYPE SPECIES. — Microberardius africanus n. gen., n. sp., by present designation. ETYMOLOGY. — From the Ancient Greek "mikros", small and Berardius, a Recent ziphiid genus. Microberardius n. gen. for the small size of the species and its cranial similarities with Berardius spp. Gender masculine. DIAGNOSIS. — Same as for the species., Published as part of Bianucci, Giovanni, Lambert, Olivier & Post, Klaas, 2007, A high diversity in fossil beaked whales (Mammalia, Odontoceti, Ziphiidae) recovered by trawling from the sea floor off South Africa, pp. 561-618 in Geodiversitas 29 (4) on page 565, DOI: 10.5281/zenodo.4651080

Genus Xhosacetus n. gen. TYPE SPECIES. — Xhosacetus hendeysi n. gen., n. sp., by present designation. ETYMOLOGY. — From Xhosa, one of the official languages of South Africa, characterized by prominent clicks (the word Xhosa itself starts with a click), somewhat reminiscent of the echolocative clicks produced by odontocetes, and from Latin "cetus", whale. Gender masculine. DIAGNOSIS. — Same as for the species., Published as part of Bianucci, Giovanni, Lambert, Olivier & Post, Klaas, 2007, A high diversity in fossil beaked whales (Mammalia, Odontoceti, Ziphiidae) recovered by trawling from the sea floor off South Africa, pp. 561-618 in Geodiversitas 29 (4) on page 592, DOI: 10.5281/zenodo.4651080

Genus Pterocetus n. gen. TYPE SPECIES. — Pterocetus benguelae n. gen., n. sp., by present designation. ETYMOLOGY. — From Ancient Greek "pteryx", wing, for the large wing-like preorbital processes and from Latin "cetus", whale. Gender masculine. DIAGNOSIS. — Same as for the species., Published as part of Bianucci, Giovanni, Lambert, Olivier & Post, Klaas, 2007, A high diversity in fossil beaked whales (Mammalia, Odontoceti, Ziphiidae) recovered by trawling from the sea floor off South Africa, pp. 561-618 in Geodiversitas 29 (4) on page 595, DOI: 10.5281/zenodo.4651080

Subfamily ZIPHIINAE Gray, 1850 TYPE GENUS. — Ziphius Cuvier, 1823. OTHER GENERA INCLUDED. — Aporotus, Beneziphius, Caviziphius, Choneziphius, Messapicetus, Tusciziphius, Ziphirostrum and Izikoziphius n. gen. EMENDED DIAGNOSIS. — The subfamily Ziphiinae differs from all other Ziphiidae in having the contact between nasal and premaxillary crest reduced and the transverse premaxillary crest directed anterolaterally. It further differs from the Berardiinae in the lack of a nodular interparietal on the vertex, from the Hyperoodontinae, Khoikhoicetus n. gen., Pterocetus n. gen., Xhosacetus n. gen. (three new genera described below), and Tasmacetus in the lack of an intrusion of the nasal into the narrow premaxillary crest., Published as part of Bianucci, Giovanni, Lambert, Olivier & Post, Klaas, 2007, A high diversity in fossil beaked whales (Mammalia, Odontoceti, Ziphiidae) recovered by trawling from the sea floor off South Africa, pp. 561-618 in Geodiversitas 29 (4) on page 570, DOI: 10.5281/zenodo.4651080

Genus Khoikhoicetus n. gen. TYPE SPECIES. — Khoikhoicetus agulhasis n. gen., n. sp., by present designation. ETYMOLOGY. — Khoikhoi is one of the ethnic groups occupying south-western Africa, closely related to the Bushmen, "cetus" from Latin, whale. Gender masculine. DIAGNOSIS. — Same as for the species.