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1

Phylogeny of the ammonite family Aulacostephanidae Spath, 1924 during the Late Oxfordian and the Early Kimmeridgian in Europe: Main lineages, patterns of evolution and sedimentological to palaeogeographical controls on evolutionary development

Wierzbowski Andrzej

Volumina Jurassica

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2022

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Vol. 20

59--128

EN

The evolutionary history of the Aulacostephanidae presented here includes the interval of about 5 Ma of the Late Oxfordian and Early Kimmeridgian ranging from the origin of the family to is maximal development. The development and biogeographical distribution of aulacostephanids in Europe were related mostly to sea-level changes and tectonics. The appearance of the ancestor genus Decipia and the following genus Ringsteadia was controlled by marine transgressions during the Late Oxfordian which stimulated also the distribution of these ammonites in Subboreal and Submediterranean Europe. The main faunal turnover at the Oxfordian/Kimmeridgian boundary was related to allopatric speciation correlated to separation of the aulacostephanid assemblages: it resulted in the appearance of the main Ringsteadia-Pictonia-Rasenia lineage in NW Subboreal Europe and the side-lineages Ringsteadia-Vielunia-Eurasenia/Involuticeras and Ringsteadia-Vineta-Balticeras-Rasenioides in NE Subboreal and Central Submediterranean Europe. A strong development of the shallow-water carbonate platforms during the Early Kimmeridgian stimulated the development of still another Pictonia (Pomerania) - Rasenia (Pachypictonia) lineage. The main faunal turnover correlated to a large transgression at the end of the Early Kimmeridgian resulted in the sudden distribution of the new aulacostephanid faunas over large areas of northern and central Europe, and opened a new stage in the evolutionary development of the family.

2

Upper upper Albian (Mortoniceras rostratum Zone) cephalopods from Clansayes (Drôme, south-eastern France)

Jattiot Romain, Lehmann Jens, Latutrie Benjamin, Tajika Amane, Vennin Emmanuelle, Vuarin Pauline, Brayard Arnaud, Fara Emmanuel, Trincal Vincent

Acta Geologica Polonica

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2022

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Vol. 72, no. 2

187--233

EN

We document an upper upper Albian (Mortoniceras rostratum Zone) cephalopod assemblage from Clansayes (Drôme, south-eastern France). Although fossils are rare in local exposures and in the single sampled level, a decade of intensive fossil collecting yielded 290 ammonite and 5 nautilid specimens. In total, we describe 1 species of nautilid and 24 species (within 17 genera) of ammonites, including 13 heteromorphs. Only two of these ammonite taxa were previously recorded from the upper upper Albian at Clansayes, which demonstrates the value of this fauna with regard to taxonomy, palaeobiology and palaeobiogeography. Based on morphological and biometric analyses performed on an extensive material (104 specimens), we discriminate two species for the heteromorphic ammonite genus Mariella Nowak, 1916 within the Mortoniceras rostratum Zone. In addition, we investigate shell chirality patterns in Mariella from the late Albian of southern France. Upon comparison of the Clansayes material with older material from the immediately underlying upper Albian Mortoniceras fallax Zone at the neighbouring Salazac locality, we identify an increase in the proportion of sinistral specimens. This observed increase in the frequency of sinistral Mariella specimens may hypothetically be part of a global evolutionary pattern, considering that nearly all documented younger Cenomanian Mariella (and more generally Cenomanian turrilitids) are sinistral.

3

New records of Tmaegoceras lacordarii (Michelin, 1835) from the Lower Jurassic Arietenkalk Formation of SW Germany and its systematic relationships

Schweigert Günter, Scherzinger Armin, Gräbenstein Stefan

Volumina Jurassica

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2021

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Vol. 19, no. 1

95--108

EN

New material of the enigmatic cosmopolitan ammonite genus Tmaegoceras Hyatt, 1889 is reported from the upper Lower Sinemurian (Bucklandi Zone, ‛cf. pinguisʼ Biohorizon) of SW Germany. It is better preserved than previously described material. All specimens are assigned to Tmaegoceras lacordarii (Michelin, 1835), an almost forgotten subjective senior synonym of Tmaegoceras crassiceps Pompeckj, 1901. The presence of an extreme rursiradiate ribbing style in some specimens allows a better understanding of this genus and provides a hint for its systematic affiliation. This diagnostic ribbing style is shared with some extremely rare Alpine taxa such as Ammonites salinarius Hauer, 1846 and “Arietites” subsalinarius Wähner, 1891. Tmaegoceras is included here in Pseudotropitinae Donovan, 1973. Pseudotropitinae are possibly an early offshoot of Arietitidae indigenous of the Panthalassa Realm that occasionally spread into the Tethys and its adjacent shelves. A phyletic relationship with Late Triassic Tropitidae Mojsisovics, 1875, however, cannot be excluded either.

4

The microcrinoid taxonomy, biostratigraphy and correlation of the upper Fredericksburg and lower Washita groups (Cretaceous, middle Albian to lower Cenomanian) of northern Texas and southern Oklahoma, USA

Gale Andrew Scott, Rashall Jenny Marie, Kennedy William James, Holterhoff Frank Koch

Acta Geologica Polonica

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2021

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Vol. 71, no. 1

1--52

EN

The stratigraphy of the upper Fredericksburg and lower Washita groups of northern Texas and southern Oklahoma is described, and biostratigraphical correlation within the region, and further afield, using micro-crinoids, ammonites, planktonic foraminiferans and inoceramid bivalves is summarised. The taxonomy of the roveacrind microcrinoids is revised by the senior author, and a new genus, Peckicrinus, is described, with the type species Poecilocrinus porcatus (Peck, 1943). New species include Roveacrinus proteus sp. nov., R. morganae sp. nov., Plotocrinus reidi sp. nov., Pl. molineuxae sp. nov., Pl. rashallae sp. nov. and Styracocrinus thomasae sp. nov. New formae of the genus Poecilocrinus Peck, 1943 are Po. dispandus forma floriformis nov. and Po. dispandus forma discus nov. New formae of the genus Euglyphocrinus Gale, 2019 are E. pyramidalis(Peck, 1943) forma pyramidalis nov., E. pyramidalis forma radix nov. and E. pyramidalis forma pentaspinusnov. The genera Plotocrinus Peck, 1943, Poecilocrinus and Roveacrinus Douglas, 1908 form a branching phylogenetic lineage extending from the middle Albian into the lower Cenomanian, showing rapid speciation, upon which a new roveacrinid zonation for the middle and upper Albian (zones AlR1-12) is largely based. Outside Texas and Oklahoma, zone AlR1 is recorded from the lower middle Albian of Aube (southeastern France) and zones AlR11-CeR2 from the Agadir Basin in Morocco and central Tunisia. It is likely that the zonation will be widely applicable to the middle and upper Albian and lower Cenomanian successions of many other regions.

5

Stratigraphy of the Albian-Cenomanian boundary interval in the Agadir Basin, Morocco: ammonites, microcrinoids, planktonic foraminifera

Gale Andrew Scott, Kennedy William James, Petrizzo Maria Rose

Acta Geologica Polonica

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2021

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Vol. 71, no. 4

453--480

EN

The uppermost Albian and lowermost Cenomanian succession at Abouda Plage, north of Agadir, in the Agadir Basin, western Morocco, is described in detail, and ammonites, microcrinoids and planktonic foraminifera are recorded and illustrated. The lower part of the Aït Lamine Formation yields ammonites indicative of the Pervinquieria (Subschloenbachia) rostrata and P. (S.) perinflata ammonite zones, and the Thalmanninella appenninica planktonic foraminiferan Zone. The base of the Cenomanian is identified at 42.2 m above the base of the Aït Lamine Formation, based on the lowest occurrence of the planktonic foraminiferan Thalmanninella globotruncanoides Sigal, 1948. Lower Cenomanian ammonites of the Graysonites adkinsi Zone enter 3 m higher in the succession. Microcrinoid zones AlR11 and AlR12 are identified in the Upper Albian, and the base of the CeR1 Zone coincides with the lowest occurrence of Cenomanian ammonites. The ammonite and microcrinoid occurrences and detailed distributions are very similar to those found in north central Texas, which, in the Cenomanian, was 5,300 km to the west. The new records suggest that the G. adkinsi Zone is equivalent to the uppermost (Lower Cenomanian) part of the Pleurohoplites briacensis Zone of the Global Stratotype Section for the base of the Cenomanian stage. An hiatus, of global extent, immediately underlies the base of the G. adkinsi Zone and is represented in the Agadir Basin by an erosion surface containing bored and encrusted hiatus concretions.

6

On some Turonian and Coniacian ammonites from central Colombia

Kennedy William James

Acta Geologica Polonica

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2021

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Vol. 71, no. 3

259--285

EN

The rich collections of Turonian and Coniacian ammonites from Colombia, housed in the University of California Museum of Paleontology, Berkeley, are described, with 20 species recognized, referred to the genera Reymenticoceras Kennedy, 2018, Vascoceras Choffat, 1898, Fagesia Pervinquière, 1907, Wrightoceras Reyment, 1954a, Subprionocyclus Shimizu, 1932, Subprionotropis Basse, 1951, Prionocycloceras Spath, 1926, Barroisiceras de Grossouvre, 1894, Forresteria Reeside, 1932, Niceforoceras Basse, 1948, Peroniceras de Grossouvre, 1894, Gauthiericeras de Grossouvre, 1894, Protexanites Matsumoto, 1955, and Metaptychoceras Spath, 1926. One species, Reymenticoceras ornatum, is new. Most of the species described can be assigned to the substages and ammonite zones recognized in Western Europe.

7

On imperfectly known Hauterivian representatives of the families Holcodiscidae Spath, 1923 and Barremitidae Breskovski, 1977 in Butkov Quarry (Central Western Carpathians, Slovakia)

Vašíček Zdeněk, Klein Jaap

Acta Geologica Polonica

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2021

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Vol. 71, no. 4

433--451

EN

In Butkov Quarry, ammonites of the families Holcodiscidae Spath, 1923 and Barremitidae Breskovski, 1977 occur in the pelagic Lower Cretaceous pelagic deposits of the Manín Unit. This contribution discusses the taxonomy of both families and presents their distribution in the layered sequences of the quarry. The genus Spitidiscus Kilian, 1910 classified as a member of the Superfamily Perisphinctoidea Steinmann in Steinmann and Döderlein, 1890 is an important representative of the Holcodiscidae from a stratigraphic point of view. In areas where the zonal index Acanthodiscus radiatus (Bruguière, 1789) does not occur, as in Butkov Quarry, the first representatives of Spitidiscus indicate the base of the Hauterivian. The genus Plesiospitidiscus Breistroffer, 1947 was long regarded as a member of the Superfamily Desmoceratoidea Zittel, 1895. This superfamily was based on its type species, Eodesmoceras celestini (Pictet and Campiche, 1860), which is not Valanginian in age, as now clearly proven. As a consequence, this superfamily is considered invalid. Vermeulen and Lahondère (2011) proposed an alternative by selecting a suitable initial genus, namely Plesiospitidiscus, for the Family Barremitidae, Superfamily Barremitoidea Breskovski, 1977 (nom. transl. Vermeulen and Lahondère, 2011).

8

The Bajocian to Kimmeridgian (Middle to Upper Jurassic) ammonite succession at Sentralbanken High (core 7533/3-U-1), Barents Sea, and its stratigraphical and palaeobiogeographical significance

Andrzej Wierzbowski, Morten Smelror

Volumina Jurassica

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2020

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Vol. 18, no. 1

1--22

EN

Ammonites recovered from Upper Bajocian to Upper Kimmeridgian strata in a core drilled at Sentralbanken High in the northern Barents Sea are described and chronostratigraphically interpreted. The lower part of the core comprises Upper Bajocian to Upper Callovian deposits of the Fuglen Formation with ammonites of the genus Cranocephalites near the base, and Longaeviceras in the upper part. The overlying Oxfordian to Kimmeridgian deposits of the Hekkingen Formation are thin and condensed. The Hekkingen Formation is dominated by Boreal cardioceratid ammonites (Cardioceras, Amoebites, Euprionoceras, Hoplocardioceras), with numerous Subboreal aulacostephanid ammonites (Rasenia, Zenostephanus) at two levels. The occurrences of Boreal and Subboreal ammonites are discussed in relation to the palaeogeography and fluctuations of ammonite faunas within the Boreal Realm during the Kimmeridgian with special attention to levels rich in Subboreal ammonites whose appearance has been controlled by tectonic and climatic factors. The uppermost part of the succession deposited during a time of maximum flooding in the Late Kimmeridgian is dominated by Boreal ammonites.

9

Hypowaagenia nov. gen., a rare genus of giant aspidoceratid ammonite from the Upper Jurassic of Southern Germany

Schweigert Günter, Schlampp Victor

Volumina Jurassica

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2020

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Vol. 18, no. 1

23--36

EN

A new genus, Hypowaagenia (type species: H. endressi nov. sp.), is introduced for previously unknown large-sized macroconchiate aspidoceratid ammonites with an umbilical and a ventrolateral row of spines. In the medium and adult stages irregular ribs interconnect these spines. The oldest unequivocal record of this genus comes from the Early Kimmeridgian Planula Zone, whereas the type material of H. endressi nov. sp. comes from the upper Platynota Zone/? lowermost Hypselocyclum Zone. Corresponding microconchs have not yet been identified. Although all unequivocal records come from Southern Germany, a Tethyan origin is most likely for these aspidoceratids. Another, stratigraphically younger species tentatively included in Hypowaagenia is Aspidoceras acanthomphalum (Zittel, 1870), which is, however, only recorded yet by mesoconchiate specimens. The ammonite fauna of the type horizon of H. endressi nov. sp. is briefly characterized and termed as the geniculatum Biohorizon of the late Platynota Zone.

10

Arietites solarium (Quenstedt, 1883) – a diagnostic ammonite species in the Lower Jurassic (Early Sinemurian, Bucklandi Zone) of SW Germany

Scherzinger Armin, Gräbenstein Stefan, Schweigert Günter

Volumina Jurassica

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2020

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Vol. 18, no. 1

37--46

EN

The coarse-ribbed and big-sized Arietites solarium (Quenstedt, 1883) is one of the largest-grown and most iconic ammonite taxa in the entire Swabian Lower Jurassic; however, despite previous revisions including the designation of a lectotype, there has been some confusion concerning its correct identification, and its type horizon within the Lower Sinemurian Arietenkalk Formation was not exactly known. Arietites solarium characterises the herein introduced solarium Biohorizon of the upper Bucklandi Zone of the Sinemurian. For nomenclatorial stability, we designate a neotype based on the only surviving specimen of Quenstedtʼs original type series. In addition, we provide a preliminary succession of recognized biohorizons in the Lower Sinemurian of Swabia, which will make correlations with other areas more reliable.

11

A microconchiate Hypowaagenia Schweigert and Schlampp, 2020 (Aspidoceratidae, Hybonoticeratinae) from the Upper Jurassic of Southern Germany

Schweigert Günter, Schlampp Victor

Volumina Jurassica

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2020

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Vol. 18, no. 2

115--120

EN

The previously unknown microconch which corresponds to the recently introduced Late Jurassic aspidoceratoid ammonite genus Hypowaagenia Schweigert and Schlampp, 2020, is reported from beds of the topmost Platynota Zone or basal Hypselocyclum Zone of Franconia. This record indicates that these exotic ammonite findings are not of long-drifting necroplanktonic shells, but stem from animals that have spread over this area after immigration from the Tethys

12

Upper Albian, Cenomanian and Upper Turonian ammonite faunas from the Fahdène Formation of Central Tunisia and correlatives in northern Algeria

Kennedy William James

Acta Geologica Polonica

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2020

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Vol. 70, no. 2

147--272

EN

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.

13

Pseudosonninia, a new genus of oppeliid ammonite (Haploceratoidea) from the Callovian (Middle Jurassic) of the Neuquén Basin, Argentina

Parent Horacio, Garrido Alberto C., Schweigert Günter, Brambilla Luciano

Volumina Jurassica

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2019

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Vol. 17, no. 1

39--48

EN

From the uppermost part of the Los Molles Formation (upper Lower and lower Middle Callovian) in Chacay Melehué (Neuquén Province, Argentina), a group of hecticoceratine ammonites with a conspicuous morphology not assimilable to any known genus of this subfamily has been recently discovered. These forms are inflated oxycones with a prominent, sharp keel developed from the juvenile phragmocone up to the adult peristome. The new genus Pseudosonninia is established on the basis of these ammonites, with Pseudosonninia chacaymelehuensis n. gen. n. sp. as its type species. The new genus seems to be endemic to the Neuquén Basin and is recorded here from the upper Lower and lower Middle Callovian of Chacay Melehué and Río de Los Patos.

14

Ammonite stratigraphy and organic matter of the Pałuki Fm.n(Upper Kimmeridgian–Lower Tithonian) from the central-eastern part of the Łódź Synclinorium (Central Poland)

Wierzbowski Andrzej, Wierzbowski Hubert

Volumina Jurassica

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2019

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Vol. 17, no. 1

49--80

EN

The ammonite biostratigraphy as well as the organic matter content, its type and maturity of the Pałuki Formation, belonging to the fine, siliciclastic Kimmeridge Clay type facies, were investigated in five deep boreholes from the central-eastern part of the Łódź Synclinorium in Central Poland. The studied deposits are assigned to the Eudoxus and Autissiodorensis zones of the Upper Kimmeridgian as well as the Klimovi, Sokolovi, Pseudoscythica and Puschi (=Tenuicostata) zones of the Lower Tithonian (“Lower Volgian”). The Pałuki Formation shows in its lower and middle parts average TOC concentrations of ca. 2.5 wt.% and prominent, restricted increases in organic matter content, which are found in the mid-Eudoxus Zone, the lowermost part of the Autisiodorensis Zone, and at the Sokolovi–Pseudoscythica zone boundary. These stratigraphical intervals correlate well with rich in organic matter levels present in the Kimmeridge Clay Formation of NW Europe. The periodic expansions of Submediterranean and Subboreal-Boreal ammonites corresponded mostly to the transgressive phases, often correlated with a higher content of organic matter. The development of special morphologies of ammonites, such as the small-sized, nectopelagic forms of Nannocardioceras in the Late Kimmeridgian, has also been related to the deposition of shales rich in organic matter during the transgression maxima. The organic matter present in the Pałuki Formation mostly consists of Type II kerogen and is immature or early mature with respect to hydrocarbon generation, which is in agreement with previously published data. Evaluation of the new and published geochemical, lithological and structural data from the Pałuki Formation in the central-eastern part of the Łódź Synclinorium shows that these deposits could not have been a considerable source of crude oil or gas.

15

Upper Albian, Cenomanian and Lower Turonian stratigraphy, ammonite and inoceramid bivalve faunas from the Cauvery Basin, Tamil Nadu, South India

Gale Andrews S., Kennedy William J., Walaszczyk Ireneusz

Acta Geologica Polonica

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2019

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Vol. 69, no. 2

161--338

EN

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.

16

Tithonian stratigraphy and ammonite fauna of the Vaca Muerta Formation in Mallín Quemado (Neuquén Basin, Argentina), with remarks on the Andean chronostratigraphy

Garrido A. C., Parent H, Brambilla L.

Volumina Jurassica

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2018

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Vol. 16, no 1

1--26

EN

In the Cerro Mallín Quemado area (Sierra de la Vaca Muerta) the three members of the Vaca Muerta Formation (Portada Covunco, Los Catutos and Pichi Moncol) can be recognized, including the whole of the Tithonian rock-record. The ammonite fauna does not show significant differences with respect to that of the nearby locality Pampa Tril, but the record of faunal horizons is patchier. Eighteen species of ammonites were recorded through the studied sections, covering the whole of the Andean Tithonian. The current chronostratigraphic zonation of the Andean Tithonian is briefly discussed, updated and correlated with the most recent literature. From the current succession of ammonite bio-horizons previously defined in the basin, only three (picunleufuense alpha, picunleufuense beta and falculatum) were recognized definitely. Four other bio-horizons (perlaevis, erinoides, internispinosum alpha and vetustum) were recognized only tentatively, because the typical assemblages of morphotypes (morpho-species) were not clearly or completely recognized. The current regional time-correlation chart dated by the ammonite bio-horizons of the Neuquén Basin along a 70°W transect is updated with the results of the present study and additional information recently obtained from other localities

17

Notes on the evolution of the ammonite families Aulacostephanidae and Cardioceratidae and the stratigraphy of the uppermost Oxfordian and lowermost Kimmeridgian in the Staffin Bay sections (Isle of Skye, Northern Scotland)

Wierzbowski A., Matyja B. A., Wright J. K

Volumina Jurassica

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2018

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Vol. 16, no 1

27--50

EN

Detailed study of all the ammonite collections gathered by the authors in the Staffin Bay sections has resulted in minor changes in the distribution of ammonite taxa, and slight modification of the position of the Oxfordian/Kimmeridgian boundary. Most significant is the discovery of Pictonia (Triozites) cf. seminudata which results in the placing of the stage boundary 0.16 m below the level formerly proposed. This study discusses the evolution of the Subboreal family Aulacostephanidae, and the Boreal family Cardioceratidae, indicating changes in the patterns of individual development in the evolution of both families in terms of heterochrony. The Oxfordian/ Kimmeridgian boundary interval shows major morphological changes in both ammonite families which were released from phylogenetic constraints by heterochrony, closely related to changes in environmental conditions.

18

Detailed biostratigraphy of the Middle Callovian – lowest Oxfordian in the Mikhaylov reference section (Ryazan region, European part of Russia) by ammonites

Kiselev D. N., Rogov M. A.

Volumina Jurassica

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2018

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Vol. 16, no 1

73--186

EN

Study of the sections near the Mikhaylov (Ryazan region) has made it possible to improve the infrazonal subdivision of the Middle Callovian – Lower Oxfordian of the European Russia by ammonites. The Athleta Zone is the most complete in the studied sections. A sequence of kosmoceratid biohorizons (phaeinum, proniae, rowlstonense and kuklikum) is established here, as well as infrazonal units based on a phylogenetic sequence of species of the genus Funiferites. A study of the paleobiodiversity and frequency of occurrence of ammonites at different intervals of the section showed that the ammonite assemblages of the Athleta Zone are Sub-Boreal or Sub-Tethyan, while in the Lamberti Zone they are Boreal, and in the Lower Oxfordian they are Arctic. It is also shown that the change in ammonite composition in the sections coincides with the cycles of transgressions and regressions of Boreal basins. New species and subspecies of the ammonites Funiferites allae compressum, Cadoceras (Eichwaldiceras) intermedium, Brightia (B.) lominadzei, B. (B.) progzhellensis, B. (B.) eccentrtica, B. (Glyptia) canaliculata stankevitchae, Zieteniceras rarecostatum are described.

19

Inoceramids and associated ammonite faunas from the uppermost Turonian-lower Coniacian (Upper Cretaceous) of the Anaipadi-Saradamangalam region of the Cauvery Basin, south-east India

Walaszczyk I., Kennedy W. J., Paranjape A. R.

Acta Geologica Polonica

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2018

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Vol. 68, no. 4

663--687

EN

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) theobald ianum (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.

20

Xenosphinctes n. gen. (Ataxioceratidae, Lithacoceratinae), a new rare ammonite genus from the Lower Tithonian (Hybonotum Zone) of SW Germany

Scherzinger A., Schweigert G.

Volumina Jurassica

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2017

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Vol. 15, no 1

155--160

EN

The new monotypic ammonite genus Xenosphinctes (type species: Xenosphinctes berkai n. sp.) is established. It is recorded from the Upper Jurassic, Early Tithonian, Hybonotum Zone, Riedense Subzone, eigeltingense α horizon from the Talmühle, N of Engen, Baden-Württemberg, SW Germany.