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A comprehensive taxonomic account of fourteen ammonite species from the upper Albian succession of the Cauvery Basin, south India is presented. They belong to the genera/subgenera Gaudryceras, Anagaudryceras, Tetragonites, Puzosia (Puzosia), Puzosia (Bhimaites), Desmoceras (Desmoceras), Desmoceras (Pseudouhligella), Stoliczkaia (Stoliczkaia) and the heteromorphs Anisoceras and Mariella. Most of these ammonite species are cosmopolitan and well-known, especially from the western margin of the Tethys. The additional value of this study in contrast to earlier studies is founded in the intensive bed-by-bed collection from a well-documented measured section. This allows to establish a first detailed range chart for the uppermost Albian of this region and to correlate the Cauvery Basin section with the upper Albian Mortoniceras perinflatum Zone-Arrhaphoceras briacensis Zone interval of the Standard Tethyan Scheme.

Recent biostratigraphic and sedimentologic studies in the lower–mid Campanian ammonite-rich shelf deposits of the James Ross Basin, Antarctica made possible a precise reconstruction of facies tracts along an onshore–offshore transect about 70 km in length. In proximal, inner-shelf settings the Santa Marta Formation include trigoniid-rich coquinas and cross-bedded and massive sandstones. In distal, mid- to outer-shelf settings the age-equivalent Rabot Formation consists of bioturbated mudstones and interbedded inoceramid- and brachiopod-rich tempestites. Each of these sedimentary facies is characterized by a very distinctive ammonite facies, whose characterization along a neritic-oceanic gradient offer clues to ammonite habitats. Ammonite facies of proximal settings are dominated by relatively large and ornate kossmaticeratids, with subordinated heteromorphs, desmoceratids, gaudryceratids and tetragonitids. Taphonomy, size–frequency distribution, and non-lethal injuries attributed to arthropods consistently suggest a shallow habitat and a nektobenthic (demersal) mode of life for the kossmaticeratids. Conversely, in distal settings the ammonite facies is dominated by gaudryceratids, including large Anagaudryceras sp., and tetragonitids, with subordinated small kossmaticeratids and large pachydiscids. Restriction to offshore oceanic-influenced facies suggests that these gaudryceratids have a mesopelagic, planktic mode of life. The hamitocone heteromorphs are equally distributed in shallow and deep facies with a high degree of shell fragmentation, particularly in shallow settings. This pattern suggests that hamitocones were exposed to extensive post-mortem drift. Fil: Olivero, Eduardo Bernardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego; Argentina Fil: Raffi, María Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego; Argentina

The Quiriquina Formation in central Chile is famous for its abundant and diverse ammonite assemblages of Maastrichtian age. In the type locality around the Concepcion Bay in the Bio-Bio Region of central Chile we have identified a total of 30 species referred to 17 genera. Hypophylloceras (Neophylloceras) ramosum, H. (N.) hetonaiense, H. (N.) inflatum, H. (N.) surya, Anagaudryceras politissimum, Gaudryceras kayei, Zelandites varuna, Pseudophyllites indra, Kitchinites darwini, Kossmaticeras (Natalites) erbeni, Grossouvrites gemmatus, Gunnarites spinosissimus, Maorites densicostatus, Pachydiscus (P. ) jacquoti chilensis, Menuites fresvillensis, Diplomoceras cylindraceum, Phylloptychoceras sp., Baculites huenickeni, Baculites vicentei and Eubaculites carinatus have been recorded previously from the Quiriquina Formation. Hoploscaphites constrictus quiriquiniensis sensu WILCKENS (1904). Phyllopachyceras forbesianum, Anagaudryceras subtilineatum, Gunnarites cf. bhavaniformis and Baculites anceps are new records for the Quiriquina Formation added here. Kitchinites vicentensis n. sp., Kitchinites ifrimae n. sp., Grossouvrites joharae n. sp., Pachydiscus (P. ) gutierrezi n. sp. and Menuites gerardoi n. sp. are new. Gaudryceras kayei specimens are recorded with diameters in excess of 200 mm and present marked changes during growth. Anagaudryceras politissimum and Zelandites varuna also show strong ontogenetic changes. Kitchinites darwini of the Quiriquina Formation differs from material from Antarctica; we propose that the latter should by separated. The presence of Hypophylloceras (Neophylloceras) surya, Zelandites varuna, Pachydiscus (P. ) jacquoti, Diplomoceras cylindraceum, Baculites anceps, Eubaculites carinatus and Hoploscaphites constrictus quiriquiniensis indicates a Maastrichtian age for the Quiriquina Formation. Menuites fresvillensis confirms the late Maastrichtian age for most of the Quiriquina Formation. The assemblage presented shows cosmopolitan and Indo-Pacific affinities with a few European and Tethyan links.

Cretaceous sediments of the Yezo Group in the Yezo forearc basin-fill are widely distributed along the meridian zone of Hokkaido, Japan. The uppermost part of the Cretaceous sequence, namely the Hakobuchi Formation, ranges in age from Early Campanian to Late Maastrichtian and partly into Late Paleocene. It is subdivided into, in ascending order, the Kamikoma, Heitaro-zawa, Oku-utsunai and Utsunaigawa members in the Nakatonbetsu area, north Hokkaido. Recently, an unconformable sequence boundary was found between the Heitaro-zawa and Oku-utsunai members. A Lower Campanian and two Lower Maastrichtian inoceramid zones are established in the lower half of the Hakobuchi Formation. A lower Upper Maastrichtian ammonite fauna, composed of Anagaudryceras matsumotoi, Pseudophyllites indura and Zelandites varuna, can be recognized above the inoceramid extinction horizon in the upper Heitaro-zawa Member. Although there are no good index megafossils in the two overlying members, Glycymeris shell-beds of the basal Oku-utsunai Member overlie the Upper Maastrichtian Heitaro-zawa Member with a sharp, undulating, erosional surface. As Late Paleocene nannofossils were reported from the two upper members, the uppermost Maastrichtian and Lower Paleocene appear to have been eroded away at the unconformity. The K/Pg gap can be traced into the Oyubari and north Hobetsu areas of central Hokkaido and four drillholes offshore from Honshu in the Pacific Ocean. This might indicate large-scale subaerial erosion caused by a relative sea-level fall throughout the Yezo Basin.

Sediments of the Mendez Formation near Cerralvo, north-eastern Mexico, yield an abundant and diverse Maastrichtian ammonite assemblage. A total of 23 species referred to 18 genera are described, in addition to the possible coleoid Naefia neogaeia. The assemblage is considered to be of early Maastrichtian age on the basis of ammonite occurrences and has been dated to the lower Maastrichtian biozone CF 7 by planktic foraminifera. None of the ammonite species has been reported previously from the Mendez Formation and most species are recorded from Mexico for the first time. In addition to faunal elements known from other Gulf of Mexico localities [Baculites ovatus, Nostoceras (N.) alternatum, N. (N.) colubriformis, N. (N.) rugosum, Solenoceras reesidei] the assemblage is characterized by cosmopolitan (e.g. Anagaudryceras politissimum, Desmophyllites diphylloides, Diplomoceras cylindraceum, Gaudryceras kayei, Phyllopachyceras forbesianum, and Pseudophyllites indra) and Tethyan elements [e.g. Brahmaites (Anabrahmaites) vishnu, Fresvillia constricta, Hauericeras rembda, Solenoceras texanum, Tetragonites superstes]. Some ammonite species have been known from the Indopacific region a [e.g. Fresvillia aff. F. teres, Neophylloceras (Hypophylloceras) hetonaiense, Zelandites varuna] and are clearly cold-water species. The composition of the assemblage contrasts with other Gulf of Mexico faunas which is related to bathymetry.

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.

One of the richest and best preserved late Campanian-Maastrichtian ammonite faunas of the world occurs within the Lopez de Bertodano Formation on Seymour Island. The excellent exposure of this sequence has offered an opportunity for detailed stratigraphic study of the fauna, providing a stratigraphic control unavailable for most other Southern Hemisphere strata of similar age.Ammonites are restricted to the Cretaceous portion of the Lopez de Bertodano Formation, becoming more abundant and increasing in diversity within a 600-m interval below the Cretaceous-Tertiary boundary. The ammonite-rich levels are divided into three zones (from oldest to youngest:Pachydiscus ootacodensis, P. riccardiandP. ultimuszones), extending from the late Campanian-Maastrichtian to the latest Maastrichtian.The taxonomic study of this fauna shows a predominance of endemic taxa of the family Kossmaticeratidae, including the speciesMaorites tuberculatusHowarth,M. seymourianus(Kilian and Reboul),M. densicostatus(Kilian and Reboul),M. weddelliensisn. sp.,Grossouvrites gemmatus(Huppe) andGunnarites bhavaniformis(Kilian and Reboul). These taxa, together with the members of the family DesmoceratidaeKitchinites(Kitchinites)darwini(Steinmann) andK.(K.)lauraen. sp., are mostly restricted to the margins of the Late Cretaceous Weddellian Province that extended from southern South America to Australia.Cosmopolitan genera described in this work become more abundant up section and include the speciesAnagaudryceras seymouriensen. sp.,Zelandites varuna(Forbes),Pseudophyllites loryi(Kilian and Reboul),Diplomoceras lambiSpath,Pachydiscus(Pachydiscus)ootacodensis(Stoliczka),P.(P.)riccardin. sp. andP.(P.)ultimusn. sp.

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 ...