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The first record of the Albian ammonite Aioloceras is documented from the Kotick Point Formation, James Ross Island, northern Antarctic Peninsula. The material is identified with the type species, Aioloceras argentinum (Bonarelli, 1921), previously only known from southern Patagonia. It is associated with Desmoceras sp., Anagaudryceras sp., Parasilesites sp., Rossalites sp. and Phyllopachyceras sp. On the basis of this assemblage, the presence of the Aioloceras argentinum Assemblage Zone from Patagonia, which is considered coeval to the upper lower Albian Mammillatum Superzone, is extended to Antarctica.

A complete taxonomic survey of ammonites from the Clarence and Raukumara Series (Albian-?Santonian) is presented. Eleven new species, Anagaudryceras woodsi, Hamites (Hamites) kaiwhataensis, Turrilites (Turrilites) exutus, Hypoturrilites varians, Mariella (Mariella) thomsoni, Scaphites wellmani, S. vellai, Worthoceras parvum, W. costatum, W. johnstoni and Puzosia (Puzosia) bushgrovenis and a new subspecies, Scaphites equalis coverhamensis are erected. Anisoceras, Ammonoceratites, Idiohamites, Worthoceras, and authentic Hamites and Turrilites are recorded from New Zealand for the first time. New Zealand species of Worthoceras throw new light on the phylogenetic significance of this genus. Two formal ammonite zones, the Worthoceras parvum Assemblage Zone (lower Ngaterian) and the Scaphites equalis coverhamensis Assemblage Zone (upper Ngaterian) are established. Continued submersion of the Coverian Stage within the Ngaterian is advocated in spite of its distinctive ammonite assemblage. Relationships ...