Successions exposed in the Agadir Basin (upper Albian to middle Turonian), in the Anti-Atlas (lower Turonian) in Morocco and in central Tunisia (Cenomanian–Turonian) yield abundant microcrinoids of the family Roveacrinidae, which are described and assigned to 32 species and formae, in ten genera. The following new taxa are described: Fenestracrinus gen. nov. with the type species F. oculifer sp. nov., Discocrinus africanus sp. nov., Styracocrinus rimafera sp. nov., Lebenharticrinus quinvigintensis sp. nov., L. zitti sp. nov., Euglyphocrinus cristagalli sp. nov., E. jacobsae sp. nov., E. truncatus sp. nov., E. worthensis sp. nov., Roveacrinus gladius sp. nov., R. solisoccasum sp. nov. and Drepanocrinus wardorum sp. nov. In addition, the new subfamily Plotocrininae is erected. The stratigraphical distribution of the taxa in two important localities, Taghazout in the Agadir Basin (Morocco) and Sif el Tella, Djebel Mhrila (central Tunisia), is provided. The faunas from the uppermost Albian and lowermost Cenomanian of the Agadir Basin are nearly identical to those recorded from central Texas, USA, some 5,300 km away, and permit a detailed correlation (microcrinoid biozones CeR1 and CeR2) to be established across the southern part of the Western Tethys, independently supported by new ammonite records. For the middle and upper Cenomanian, rather few detailed records of microcrinoids are available elsewhere, and the North African record forms the basis for a new zonation (CeR3–CeR6). The distribution of Turonian Roveacrinidae in North Africa is evidently very similar to that described in the Anglo-Paris Basin, and zones TuR1–3, TuR9, 10 and 14 are recognised for the first time in the Tethys.
Over 130 species are documented from the Upper Albian, Cenomanian and Upper Turonian Fahdène Formation and correlatives in Central Tunisia and northern Algeria, based on material described by Henri Coquand (1852, 1854, 1862, 1880), Léon Pervinquière (1907, 1910), Georges Dubourdieu (1953), Jacques Sornay (1955), and new collections. The material consists predominantly of limonitic nuclei, together with adults of micromorphs. There is no continuous record, and a series of faunas are recognised that can be correlated with the zonation developed in Western Europe. These are the Upper Albian Ostlingoceras puzosianum fauna, Lower Cenomanian Neostlingoceras carcitanense and Mariella (Mariella) harchaensis faunas, the upper Lower to lower Middle Cenomanian Turrilites scheuchzerianus fauna, Middle Cenomanian Calycoceras (Newboldiceras) asiaticum fauna, Upper Cenomanian Eucalycoceras pentagonum fauna, and the Upper Turonian Subprionocyclus neptuni fauna. Two new micromorph genera are described, Coquandiceras of the Mantelliceratinae and Cryptoturrilites of the Turrilitinae. Most of the taxa present have a cosmopolitan distribution, with a minority of Boreal, North American and endemic taxa.
Nothofagaceae fossil leaves and an associated palynoflora from Late Cretaceous sediments of Vega Island, eastern Antarctic Peninsula, are presented. The leaves are described as Nothofagus sp. 1 and Morphotype LDB 1, and come from the Snow Hill Island (late Campanian-early Maastrichtian) and the López de Bertodano (late Maastrichtian) formations, respectively. The palynoflora obtained from levels immediately above and below the Nothofagus sp. 1 and in the same horizon as the Morphotype LDB 1, included terrestrial and marine elements. In the palynoflora associated with Nothofagus sp. 1, conifers are dominant and pollen grains with Nothofagus affinity are represented by four species: Nothofagidites kaitangataensis (Te Punga) Romero 1973 and Nothofagidites senectus Dettmann and Playford 1968, which belong to the ancestral pollen type, as well as Nothofagidites dorotensis Romero 1973 and Nothofagidites sp. of the brassii-type. Cryptogamic spores, marine dinoflagellate cysts and algae, among others, are part of the assemblage. The palynoflora associated with the Morphotype LDB 1 also contains abundant conifer and angiosperm pollen grains with N. dorotensis as the only Nothofagus species recorded. Marine dinoflagellate cysts are scarce while fungi and phytodebris are common elements. The joint presence of marine and non-marine palynomorphs supports a probable nearshore environment at time of deposition for both units. Pollen and spore evidence suggests a mixed conifer and angiosperm forest, with Podocarpaceae and Nothofagus as the main components, and ferns, lycopods, and mosses in the understory. This forest developed under temperate and moist conditions during the middle Campanian-Maastrichtian.
This is a second paper dealing with juvenile and little known Mesozoic gastropods from Siberia and the Timan region. This part contains description of gastropods belonging to Neogastropoda and Heterobranchia. Described are 16 species, five of them are new. They are: Sulcoactaeon uralicus, S. timanicus, S. bojarkensis (Bullinidae), Vasjugania vasjuganensis (Acteonidae), and Biplica siberica (Ringiculidae). The new genus Vasjugania (Acteonidae) is proposed. Eight species are left in the open nomenclature. The protoconch of Siberian Khetella, illustrated here for the first time, suggests that this genus belongs to Purpurinidae and the whole family is a possible stem group for the Neogastropoda. Apart from Khetella the Siberian fauna seems to be of cosmopolitan character having common elements both with Europe and North America.
The lower (but not lowermost) part of the Upper Cretaceous Anaipadi Formation of the Trichinopoly Group in the area between Kulatur, Saradamangalam and Anaipadi, in the south-western part of the Cauvery Basin in southeast India yielded rich inoceramid and ammonite faunas. The ammonites: Mesopuzosia gaudama (Forbes, 1846), Damesites sugata (Forbes, 1846), Onitschoceras sp., Kossmaticeras (Kossmaticeras) theobaldianum (Stoliczka, 1865), Lewesiceras jimboi (Kossmat, 1898), Placenticeras kaffrarium Etheridge, 1904, and Pseudoxybeloceras (Schlueterella) sp., are characteristic of the Kossmaticeras theobaldianum Zone. The absence of Peroniceras (P.) dravidicum (Kossmat, 1895) indicates the presence of only lower part of this zone, referred to the nominative Kossmaticeras theobaldianum Subzone at the localities studied. The inoceramids present are Tethyoceramus madagascariensis (Heinz, 1933) and Cremnoceramus deformis erectus (Meek, 1877), recorded for the first time from the region. The latter dates the studied interval as early early Coniacian, and allows, for the first time, direct chronostratigraphic dating of the Tethyoceramus madagascariensis Zone, and consequently also of the Kossmaticeras theobaldianum Subzone. As inoceramids occur in the middle part of the ammonite-rich interval, the Kossmaticeras theobaldianum Subzone may be as old as latest Turonian and not younger than early early Coniacian. The base of the Coniacian lies in the lower, but not lowermost part of the Anaipadi Formation. Both inoceramids and ammonites represent taxa known from Madagascar and South Africa.
The Upper Greensand Formation, mostly capped by the Chalk, crops out on the edges of a broad, dissected
plateau in Devon, west Dorset and south Somerset and has an almost continuous outcrop that runs from the Isle
of Purbeck to the Vale of Wardour in south Wiltshire. The Formation is well exposed in cliffs in east Devon and
the Isle of Purbeck, but is poorly exposed inland. It comprises sandstones and calcarenites with laterally and
stratigraphically variable amounts of carbonate cement, glauconite and chert. The sedimentology and palaeon-
tology indicate deposition in marginal marine-shelf environments that were at times subject to strong tidal and
wave-generated currents. The formation of the Upper Greensand successions in the region was influenced by
penecontemporaneous movements on major fault zones, some of which are sited over E-W trending Variscan
thrusts in the basement rocks and, locally, on minor faults. Comparison of the principal sedimentary breaks in
the succession with the sequence boundaries derived from world-wide sea-level curves suggests that local tec-
tonic events mask the effects of any eustatic changes in sea level. The preserved fauna is unevenly distributed,
both laterally and stratigraphically. Bivalves, gastropods and echinoids are common at some horizons but are
not age-diagnostic. Ammonites are common at a few stratigraphically narrowly defined horizons, but are rare
or absent throughout most of the succession. As a result, the age of parts of the succession is still poorly known
The lithostratigraphy, biostratigraphy, sequence stratigraphy, ammonite and inoceramid faunas of the Upper Albian, Cenomanian, and Lower Turonian Karai Formation, the highest unit of the Uttatur Group in the Pondicherry Sub-Basin of the Cauvery Basin in Tamil Nadu, south India, are documented. Detailed logs and descriptions of sections between Karai and Kulakkalnattam, Odiyam and Kunnam, and north-west of Garudamangalam are presented. They provide the evidence for an ammonite zonal scheme that can be correlated in detail with sequences developed in Europe, with successive Upper Albian zones of Pervinquieria (Subschloenbachia) rostrata and P. (S.) perinflata (the latter on slight evidence), Cenomanian zones of Mantelliceras mantelli, Cunningtoniceras cunningtoni, Calycoceras (Newboldiceras) asiaticum, Pseudo calycoceras harpax, Euomphaloceras septemseriatum and Pseudspidoceras footeanum. The Lower Turonian is represented by a Neoptychites cephalotus–Mytiloides borkari fauna. Over 120 ammonite species are described, of which Puzosia (Bhimaites) falx, Protacanthoceras parva, Watinoceras elegans, Euomphaloceras varicostatum, Kamerunoceras multinodosum, and Carthaginites multituberculatus are new. The new genus Kunnamiceras, with Ammonites tropicus Kossmat, 1865 as type species, is interpreted as a paedomorphic dwarf derivative of Pseudocalycoceras harpax (Stoliczka, 1864). Ammonite faunas from shales are dominated by feebly-ornamented taxa: leiostraca; those from sandstones by strongly ornamented taxa: trachyostraca, differences interpreted as reflecting the preferred habits of adults in life. 15 species of inoceramid bivalves, including a newly described species Inoceramus chiplonkari, are recognised, with a mixed East African–Euramerican–North Pacific affinity. On the basis of the stratigraphic framework developed, a sequence stratigraphic interpretation of the Karai Formation is proposed, and correlated with those recognised in Europe, Morocco, and the United States Gulf Coast and Western Interior.
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