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The ammonite succession in the Callovian, Oxfordian and Kimmeridgian of the Czorsztyn Limestone Formation, at Halka Klippe, Pieniny Klippen Belt, Carpathians

100%

Myczynski R., Wierzbowski A.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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1994

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tom 42

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nr 3

2

Les ammonites du niveau vert de Zalas [Oxfordien inferieur, Pologne du Sud]: condensation ou concentration de faunes

100%

Marchand D., Tarkowski R.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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1992

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tom 40

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nr 1

3

Mirosphinctes Schindewolf et Euaspidoceras Spath du Niveau Vert de Zalas [Pologne] [Oxfordien Inferieur, zone a cordatum]: dimorphes sexuels?

100%

Bonnot A., Neige P., Tarkowski R., Marchand D.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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1994

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tom 42

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nr 3

4

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Primary structure of the connecting ring of ammonoids and its preservation

84%

Kulicki C., Tanabe K., Landman N. H.

Acta Palaeontologica Polonica

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2007

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tom 52

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nr 4

The most distinctive and important element of the hydrostatic organ of ammonoids and nautiloids is the siphuncular tube. It consists of mineral and organic segments (so−called connecting rings). The connecting ring of ammonites never preserves its original organic matter in the mineralized state, usually having undergone diagenetic phosphatisation, more rarely, calcification, or even complete loss. Our knowledge about its original ultrastructure is based upon comparison with Recent Nautilus and phosphatised or calcified ammonite fossils. We show that depending on the taphonomic history, both calcium phosphate and calcite can participate in the diagenesis of the connecting ring wall. Under standard light microscopy, the phosphatised elements are indistinguishable from the calcified ones. Both are dark brown in colour, due to an excess of carbon. The structure of the phosphatised siphuncle does not closely replicate the structure of its organic elements. This casts doubts on conclusions of other authors who described a complex porous structure in ammonite siphuncles, which is completely dissimilar to the siphuncular structure of Recent Nautilus and suggests that this organ functioned differently in ammonites. SEM observations using a BSE detector on the calcified parts of the walls of connecting rings revealed a multilayered structure with perpendicular elements connecting particular layers, resembling the structure of a stacked nacreous layer.

5

Lower Cretaceous ammonites from Sierra del Rosario (western Cuba)

84%

Myczynski R.

Acta Palaeontologica Polonica

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1977

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tom 22

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nr 2

Lower Cretaceous ammonites from the Artemisa, Polier and Lucas Formations of the Pinar del Rio province, are described. The assemblage comprises 47 species, including four new: Karsteniceras polieri, Crioceras pinarensis, Acrioceras (Paraspinoceras) rosariensis and ?Pleurohoplites machini. Some of them are common for Cuba, Mexico and south Andes. Typical west - Tethyan ammonites form a noticeable part of the Cuban assemblage.

6

Terminal Maastrichtian ammonites from Turkmenistan, Central Asia

84%

Machalski M., Jagt J. W. M., Alekseev A. S., Jagt-Yazykova E. A.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 4

A complete uppermost Maastrichtian–Danian succession in the Sumbar River section, western Kopet Dagh (southwest Turkmenistan, Central Asia), constitutes one of the few instances in the world where the fossil record of the last ammonites can be directly positioned with respect to the iridium−rich, impact−related clay layer, which defines the Cretaceous–Paleogene (K–Pg) boundary. Two ammonite taxa, Baculites cf. vertebralis and Hoploscaphites constrictus johnjagti, range up to a level directly beneath the K–Pg boundary clay in the Sumbar River section. Thus, these two forms probably survived until the very end of the Maastrichtian in the western Kopet Dagh area. The terminal Maastrichtian ammonite records from the Sumbar River area represent the southeasternmost occurrences of these essentially Boreal taxa.

7

Short-term survival of ammonites in New Jersey after the end-Cretaceous bolide impact

84%

Landman N. H., Garb M. P., Rovelli R., Ebel D. S., Edwards L. E.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 4

A section containing the Cretaceous/Paleogene (= Cretaceous/Tertiary) boundary in Monmouth County, New Jersey, preserves a record of ammonites extending from the end of the Cretaceous into possibly the beginning of the Danian. The section includes the upper part of the Tinton Formation and lower part of the Hornerstown Formation. The top of the Tinton Formation is represented by a richly fossiliferous unit (the Pinna Layer) that contains many bivalves in life position as well as ammonite jaws preserved inside body chambers. Ammonites include Pachydiscus (Neodesmoceras) mokotibensis, Sphenodiscus lobatus, Eubaculites carinatus, E. latecarinatus, Discoscaphites iris, D. sphaeroidalis, D. minardi, and D. jerseyensis. The Pinna Layer probably represents a relatively short interval of time lasting tens to hundreds of years; it is conformably overlain by the Burrowed Unit, which contains a single fragment of Discoscaphites sp. and several fragments of E. latecarinatus, as well as several isolated specimens of ammonite jaws including two of Eubaculites. Examination of the mode of preservation of the ammonites and jaws suggests that they were fossilized during deposition of the Burrowed Unit and were not reworked from older deposits. Based on the ammonites and dinoflagellates in the Pinna Layer and the Burrowed Unit, these strata traditionally would be assigned to the uppermost Maastrichtian, corresponding to calcareous nannofossil Subzone CC26b. However, a weak iridium anomaly (500–600 pg/g) is present at the base of the Pinna Layer, which presumably represents the record of the bolide impact. Correlation with the iridium layer at the Global Stratotype Section and Point at El Kef, Tunisia, would, therefore, imply that these assemblages are actually Danian, provided that the iridium anomaly is in place and the ammonites and dinoflagellates are not reworked. If the iridium anomaly is in place, or even if it has migrated downward from the top of the Pinna Layer, the ammonites would have survived the impact at this site for a brief interval of time lasting from a few days to hundreds of years.

8

Ammonite faunal dynamics across bio-events during the mid- and Late Cretaceous along the Russian Pacific coast

84%

Jagt-Yazykova E. A.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 4

The present paper focuses on the evolutionary dynamics of ammonites from sections along the Russian Pacific coast during the midand Late Cretaceous. Changes in ammonite diversity (i.e., disappearance [extinction or emigration], appearance [origination or immigration], and total number of species present) constitute the basis for the identification of the main bio−events. The regional diversity curve reflects all global mass extinctions, faunal turnovers, and radiations. In the case of the Pacific coastal regions, such bio−events (which are comparatively easily recognised and have been described in detail), rather than first or last appearance datums of index species, should be used for global correlation. This is because of the high degree of endemism and provinciality of Cretaceous macrofaunas from the Pacific region in general and of ammonites in particular.

9

Size-shape relationships in the Mesozoic planispiral ammonites

84%

Parent H., Greco A. F., Bejas M.

Acta Palaeontologica Polonica

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2010

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tom 55

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nr 1

Ammonites are of outstanding importance in dating events of the Mesozoic and in the study of mechanisms, modes and timing of evolutionary processes. These applications rely on a detailed understanding of their morphology and the modes of variation. It has been known for a long time that their shape is composed of a number of highly correlated features. A new model, called the ADA−model, is introduced for the study of shell morphology (size and shape). The new model is based on classic dimensions which are stable parameters throughout ontogeny, giving very close agreement between pre− dictions and actual observations. It was applied in the exploration of the morphospace occupied by the planispirally coiled and the regularly uncoiled Mesozoic Ammonoidea, based on two new reduced morphospaces introduced for the analysis. Results obtained expose close relationships between size and shape, and general patterns in the ammonite shell morphol− ogy and morphogenesis. (i) The relative apertural height of the whorl section relative to the diameter of the shell (H₂/D) is involved in definition of size and shape. (ii) This same dimension shows a strong tendency to be H₂/D = 0.3. (iii) There are some geometrically possible shell shapes (or morphotypes) which seem to have not been developed since they are not known in the current record. Assuming the known ranges of protoconch size and whorl number as constraints, the ADA−model strongly suggests that these morphotypes have not been developed for the too large or too small sizes the shells would have attained, well outside of the actual size range of the planispirally coiled Ammonoidea. (iv) The law of covariation is shown to be a general pattern within the planispiral ammonites which describes structured variation of the shell shape. (v) A large fraction of the non−structured variation seems originate in the lack of correlation between the rela− tive umbilical diameter and width of the whorl section.

10

The last Cretaceous ammonites in Latin America

84%

Stinnesbeck W., Ifrim C., Salazar C.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 4

Sections yielding late Maastrichtian ammonite assemblages are rare in Latin America and precise biostratigraphic correlation with European type sections remains difficult. In all, the extinction pattern of ammonites appears to differ between sites in southern high latitudes and those in the tropics to subtropics. In austral sections of Chile, and possibly also in southern Argentina, diverse assemblages range throughout most of the substage and then show a gradual decline prior to the Cretaceous–Paleogene (K–Pg) boundary. Further north, in northeast Brazil, only two genera (Diplomoceras, Pachydiscus) range into the uppermost Maastrichtian, but disappear within the last 0.3 Ma of the Cretaceous. In tropical sections of Columbia and Mexico, the decline of ammonites started earlier and Sphenodiscus is the last ammonite known to occur in the late Maastrichtian. In all sections revised here the disappearance of ammonites was completed prior to the end of the Maastrichtian and was thus independent of the asteroid impact at, or near, the end of the Cretaceous.

11

Pliensbachian [Early Jurassic] fauna from the Pieniny Klippen Belt, Carpathians, Poland: its stratigraphic and palaeogeographic position

84%

Birkenmajer K., Myczynski R.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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1994

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tom 42

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nr 4

12

Cephalopods (Mollusca: Cephalopoda) in the palaeontological collection of the Faculty of Biology, Adam Mickiewicz University

67%

Konwerski S., Bloszyk J.

Folia Malacologica

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2012

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tom 20

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nr 1

13

New Lower Kimmeridgian ataxioceratin ammonite from the eastern Iberian Chain, Spain: Systematic, biogeographic, and biostratigraphic relevance

67%

Moliner L., Oloriz F.

Acta Palaeontologica Polonica

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2010

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tom 55

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nr 1

New ammonites collected bed−by−bed from the upper part of Ataxioceras hypselocyclum Chronozone deposits in the eastern Iberian Chain are described as Geyericeras gen. nov. The new genus includes microand macroconchiate Ataxioceratinae of small size, with moderate to loose coiling and subpolyplocoid ribs, a character crucial for its identification. Key points for the comparative identification of Geyericeras gen. nov. are: (i) microconchiate Geyericerasshow morphological convergence with evolute specimens of the stratigraphically older genus Schneidia [m]; (ii) contemporary Ataxioceratinae genera such as Ardescia [m, M] and Lithacosphinctes [m, M] did not develop subpolyplocoid ribbing; (iii) smoothing of sculpture combined with short primary ribs are not realized in Geyericeras gen. nov. [M] and can be therefore used to separate the new genus from Ataxioceras[M]; and (iv) smaller shells, and weaker and less dense ribbing with no parabolic structures differentiate Geyericeras gen. nov. [m, M] from Parataxioceras[m, M], as well as the type of subpolyplocoid ribs seen among microconchiate specimens of these two genera. The new species Geyericeras aragoniense sp. nov. is the index and guide fossil for identification of a biohorizon occurring below the first occurrence of the genus Crussoliceras in the eastern Iberian Chain.

14

The soft-tissue attachment scars in Late Jurassic ammonites from Central Russia

67%

Mironenko A. A.

Acta Palaeontologica Polonica

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2015

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tom 60

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nr 4

Soft-tissue attachment scars of two genera and four species of Late Jurassic craspeditid ammonites from the Russian Platform are described. A previously suggested relationship between lateral attachment scars and ammonoid hyponome is confirmed, however, a new interpretation is proposed for dorsal attachment scars: they could have been areas not only for attachment of the dorsal (nuchal) retractors, but also of the cephalic retractors. The new type of the soft-tissue attachment—anterior lateral sinuses, located between the lateral attachment scars and the aperture of the ammonite body chamber is described. Enclosed elliptical or subtriangular areas in apertural parts of the anterior lateral sinuses were found for the first time. Their presence and location suggest that this structure could have been used for attaching the funnel-locking apparatus, similar to those of coleoids. A transformation of shape and position of lateral attachment scars through the evolution of the Late Jurassic craspeditid lineage starting from platycones (Kachpurites fulgens) to keeled oxycones (Garniericeras catenulatum) is recognized.

15

Oyster attachment scar preservation of the late Maastrichtian ammonite Hoploscaphites constrictus

67%

Lehmann J., Wippich M. G. E.

Acta Palaeontologica Polonica

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1995

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tom 40

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nr 4

16

Campanian [Late Cretaceous] nautiloids from Sakhalin, Far East Russia

67%

Wilmsen M., Yazykova E. A.

Acta Palaeontologica Polonica

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2003

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tom 48

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nr 3

Three nautiloid taxa, Cymatoceras pseudoatlas (Yabe and Shimizu, 1924b), C. cf. bifidum Shimansky, 1975, and C. cf. honmai Matsumoto and Miyauchi, 1983, are recorded from the Campanian of Sakhalin, Far East Russia. These are the first biostratigraphically well dated nautiloids from Sakhalin, which show close affinities to nautiloid faunas from Japan (Hokkaido), the two areas having formed part of a southerly palaeobiogeographical subprovince of the North Pacific Province. Possible relationships between shell form/ornament and preferred habitats of Late Cretaceous nautiloids are discussed. Coarsely ribbed (“cymatoceratid”), depressed nautiloids seem to predominate in nearshore environments. This may be regarded as an adaptive response to increasing predation pressure by durophages, especially in shallow water settings, which may have triggered the development of defensive morphologies (i.e., ornamented, predation−resistant shells) in Cretaceous shallow−water nautiloids.

17

Lower Tithonian microconchiate simoceratins from eastern Mexico: Taxonomy, biostratigraphy, and palaeobiogeography

59%

Villasenor A., Oloriz F., Gonzalez-Arreola C.

Acta Palaeontologica Polonica

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2011

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tom 56

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nr 1

The precise record of simoceratins sampled bed−by−bed is first reported from Mexico (Mazatepec area in Puebla, central−eastern Mexico), as well as the existence of lappeted peristomes in these ammonites. Both Pseudovolanoceras aesinense and the subspecies Pseudovolanoceras aesinense chignahuapense are shown to occur among Mexican simoceratins. The European species and the Mexican subspecies share the same stratigraphic range in the studied sections, yet they differ in ephebic sculpture. Ecological adaptation to neritic seas corresponding to eastern Mexico areas is interpreted, forcing phenotypic deviation with geographic significance, i.e., subspeciation. The new subspecies would indicate stratigraphic horizons within the Semiformiceras semiforme/Haploceras verruciferum Chronozone in the Mediterranean Tethys. A revision of contemporaneous simoceratins in the Americas is founded on a comparative analysis with respect to the European species P. aesinense.

Ograniczanie wyników

The ammonite succession in the Callovian, Oxfordian and Kimmeridgian of the Czorsztyn Limestone Formation, at Halka Klippe, Pieniny Klippen Belt, Carpathians

Les ammonites du niveau vert de Zalas [Oxfordien inferieur, Pologne du Sud]: condensation ou concentration de faunes

Mirosphinctes Schindewolf et Euaspidoceras Spath du Niveau Vert de Zalas [Pologne] [Oxfordien Inferieur, zone a cordatum]: dimorphes sexuels?

Primary structure of the connecting ring of ammonoids and its preservation

Lower Cretaceous ammonites from Sierra del Rosario (western Cuba)

Terminal Maastrichtian ammonites from Turkmenistan, Central Asia

Short-term survival of ammonites in New Jersey after the end-Cretaceous bolide impact

Ammonite faunal dynamics across bio-events during the mid- and Late Cretaceous along the Russian Pacific coast

Size-shape relationships in the Mesozoic planispiral ammonites

The last Cretaceous ammonites in Latin America

Pliensbachian [Early Jurassic] fauna from the Pieniny Klippen Belt, Carpathians, Poland: its stratigraphic and palaeogeographic position

Cephalopods (Mollusca: Cephalopoda) in the palaeontological collection of the Faculty of Biology, Adam Mickiewicz University

New Lower Kimmeridgian ataxioceratin ammonite from the eastern Iberian Chain, Spain: Systematic, biogeographic, and biostratigraphic relevance

The soft-tissue attachment scars in Late Jurassic ammonites from Central Russia

Oyster attachment scar preservation of the late Maastrichtian ammonite Hoploscaphites constrictus

Campanian [Late Cretaceous] nautiloids from Sakhalin, Far East Russia

Lower Tithonian microconchiate simoceratins from eastern Mexico: Taxonomy, biostratigraphy, and palaeobiogeography