A new genus of Triassic Nautilida, Gyronautilus, is proposed for material from the Lower Triassic of South Primorye, Russia. The new genus differs from previous known genera of the family Grypoceratidae by its gyroconic shell with subrectangular whorl sections and a near-marginal siphuncle. A new subfamily, Gyronautilinae, within the Grypoceratidae is also proposed.

View full abstract

Hoploparia sp. (Astacidea, Nephropidae) and Callianassa (s. l.) sakakuraorum sp. nov. (Thalassinidea, Callianassidae) are described from the Lower Cretaceous Arida Formation in Wakayama Prefecture, Japan. Both genera are recognized for the first time from Lower Cretaceous (Barremian) deposits of Japan. These occurrences indicate that Hoploparia and Callianassa reached Japan-the west side of the North Pacific region-by the Barremian.

View full abstract

Twelve species in 11 genera of decapod crustaceans are recorded from Palaeogene rocks of Nagasaki and Saga Prefectures, Kyushu, Japan. Carinocarcinoides gen. nov. (Goneplacidae) is proposed to accommodate Carinocarcinoides carinatus sp. nov. and Varuna angustifrons Karasawa from the lower Oligocene Kishima Group. A new monotypic genus, Cicarnus (Portunidae), is erected with Cicarnus fumiae sp. nov. from the middle Eocene Okinoshima Group. Neocallichirus sakiae sp. nov. (Callianassidae) is described from the lower Oligocene Kishima Group. Axius (s. l.) sp. and Euphylax? sp. from the Kishima Group represent the first records for both genera from the Oligocene of Japan. The occurrence of Minohellenus macrocheilus Kato and Karasawa extends the known geologic range of this species back to the lower Oligocene. A new description is given for Collinsius simplex Karasawa.

View full abstract

Three Bashkirian (Middle Carboniferous) species of orthocerid cephalopods, the orthoceratid Hidamichelinoceras bandoi gen. et sp. nov. and the pseudorthoceratids Mooreoceras sp. and Adnatoceras ichinotaniense Niko and Hamada, 1987, are described (or redescribed) from the Ichinotani Formation, Central Japan based on new material. The siphuncular structure of Hidamichelinoceras is shared with Michelinoceras, but this new genus is characterized by its broadly cone-shaped initial camera and rapid shell expansion. The discovery of Mooreoceras, which previously had been known only from the Hikoroichi Formation in Japan, supports a paleobiogeographic link between the Fukuji and southern Kitakami areas in the Carboniferous. The apical shell diagnosis of Adnatoceras ichinotaniense is added.

View full abstract

This paper contains the descriptions of Ostlingoceras (Ostlingoceras) bechei (Sharpe, 1857), O. (O.) aff. bechei, and Neostlingoceras carcitanense (Matheron, 1842), all from the lower Cenomanian of the Mikasa and Kotanbetsu areas; also those of two new species Neostlingoceras asiaticum and N. cobbani from the middle Cenomanian of the Mikasa area. A new genus Hypostlingoceras is established, with descriptions of two new species, H. japonicum (type species) and H. mikasaense, from the lower Cenomanian of the same area.

View full abstract

The Paleogene marine sequences of the Dungan, Shaheed Ghat, Baska and Kirthar Formations are exposed at several places in the Sulaiman fold and thrust belt in central Pakistan. The lowermost Dungan Formation unconformably overlies the open marine Maastrichtian Pab Sandstone, being distributed widely along both limbs of the Zinda Pir Anticline area and in the Rakhi Nala area. The Dungan Formation is composed mainly of black-colored siltstone with some intercalations of sandstone in the base and many interbeds of limestone in the upper part. The strata from all three sections have yielded abundant and well-preserved Paleocene-Eocene planktic foraminifers and about 50 species belonging to nine genera are identified from this sequence. Zones P3 to P7 of the tropical zonal schemes were recognized, furthermore, Zones P3 and P4 are subdivided into two subzones (Subzones A and B), respectively. These assemblages contain a new species Globanomalina rakhiensis in the Rakhi Nala section. A late Paleocene through early Eocene age is assigned to the Dungan Formation. The quantitative data of each species indicates that the Dungan Formation was deposited in a relatively deep to open marine environment, probably forming a continental slope dipping from east to west.

View full abstract