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Sporadoceratid ammonoids from the Shotori Range (east-central Iran) - a case of putative gigantism caused by hydraulic sorting?

Korn Dieter, Ghaderi Abbas, Devaere Léa, Hairapetian Vachik, Khanehbad Mohammad, Belka Zdzisław

Acta Geologica Polonica

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2019

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Vol. 69, no. 1

27--49

EN

The Shotori Range of east-central Iran (east of Tabas) has yielded Famennian ammonoid assemblages dominated by the family Sporadoceratidae. Four genera Maeneceras Hyatt, 1884, Iranoceras Walliser, 1966, Sporadoceras Hyatt, 1884 and Erfoudites Korn, 1999 are represented. The conodont assemblage of one sample containing Iranoceras revealed an Upper marginifera Zone age. The ammonoid assemblages are characterised by comparatively large specimens; they reach conch diameters of 300 mm (including the body chamber) and the mean size is larger than 100 mm. The preservation of the material from the Shotori Range and size comparison with sporadoceratid assemblages from the Anti-Atlas of Morocco and the Rhenish Mountains of Germany suggest that hydraulic sorting has resulted in a bias towards large conchs, explaining the size distribution, rather than latitudinal differences. The new species Maeneceras tabasense is described; the genus Iranoceras is revised with a new description of the two species Iranoceras pachydiscus (Walliser, 1966) and Iranoceras pingue (Walliser, 1966).

2

The Upper Campanian - lower Maastrichtian cephalopod fauna of Botellos, Nuevo León: a key to understand faunal turnover across the Campanian-Maastrichtian boundary in NE Mexico

Ifrim C., Lara de la Cerda J. E., Peña Ponce V. H., Stinnesbeck W.

Acta Geologica Polonica

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2017

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Vol. 67, no. 1

145--162

EN

A new cephalopod collection from the Campanian-Maastrichtian boundary interval of NE Mexico, consisting of 1076 individuals assigned to 29 species and 22 genera is presented. This collection is a mix of ammonoids, one coleoid and one nautilid, which originate from at least three ammonoid biozones: The upper Campanian Exiteloceras jenneyi and Nostoceras (Nostoceras) hyatti zones, and the lower Maastrichtian Pachydiscus (Pachydiscus) neubergicus Zone. The age of the collection is thus middle late Campanian to late early Maastrichtian, and it closes a stratigraphic gap between faunas described formerly from this region. The specimens are nuclei collected from the desert pavement. The abundance of specimens allows for a comparison to other Campanian-Maastrichtian ammonoid records from Mexico, North America and Europe.

3

Depositional history of the youngest strata of the Sassendalen Group (Bravaisberget Formation, Middle Triassic-Carnian) in southern Spitsbergen, Svalbard

Krajewski K., Weitschat W.

Annales Societatis Geologorum Poloniae

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2015

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Vol. 85, No. 1

151--175

EN

The Bravaisberget Formation of southern Spitsbergen (the youngest formation of the Sassendalen Group; Middle Triassic–Carnian) comprises a succession of organic-rich and sandy phosphogenic deposits that developed in a marginal part of the Svalbard basin, in response to a high biological productivity event in the Barents Shelf. The basin margin was bounded on the southwest by the elevated structure of the Sørkapp-Hornsund High. North of the high, the subsiding shelf bottom stretched from southern to western Spitsbergen. The organic-rich, fine-grained sedimentation that gave rise to the formation of the Passhatten Member extended southward after the Anisian transgression; it reached the topmost part of the Sørkapp -Hornsund High during the maximum flooding of the basin in the early Ladinian. The sudden appearance of deltaic deposits of the Karentoppen Member directly after the maximum flooding was a consequence of short-lived tectonic activity of the Sørkapp -Hornsund High and the adjacent land area. Reworking and redistribution of the deltaic sediments during the Ladinian brought about the formation of shallow-marine clastic facies of the Somovbreen Member. Decreasing depositional rates close to the Middle-Late Triassic boundary led to a regional hiatus and the formation of a condensed phosphorite horizon at the top of the Somovbreen Member. The sedimentation of the Bravaisberget Formation ended in the early Carnian. The youngest siliciclastic and spiculitic sediments of the Van Keulenfjorden Member were deposited in southern and western Spitsbergen in shallow- to marginal-marine environments.

4

The youngest Devonian record of "Housean pits" in ammonoids

Rakociński M.

Geological Quarterly

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2012

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Vol. 56, No 2

387-390

EN

An unusual occurrence of parasitic "Housean pits" in internal mould of ammonoid specimen referred to as Felisporadoceras cf. subvaricatum (Sobolew) from Middle Famennian of Poland are described. Hitherto the youngest representatives of goniatites showing a pitting on the internal moulds were known from the Middle Devonian (lower Givetian), thus, most probably the presented material constitutes the youngest world record of this phenomenon.

5

Towards better understanding of ammonoid taphofacies of pelagic carbonate platforms

Tomasovych A., Schlogl J.

Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

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2009

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T. 35, z. 3/1

101-102

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The ecological significance of solitary coral and bivalve epibionts on Lower Cretaceous (Valangianian-Aptian) ammonoids from the Italian Dolomites

Lukeneder A.

Acta Geologica Polonica

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2008

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Vol. 58, no. 4

425-436

EN

Lower Cretaceous deposits of the Puez section in the Dolomites (northern Italy) yielded a rich ammonoid fauna (28 genera, n = 424) showing unique epifaunal encrustations by the ahermatypic solitary scleractinian ?Cycloseris LAMARCK, 1801. The coral encrusted only the outer shell surfaces of the ammonoids; the inner surface remained unaffected. Such a Cretaceous community and the relationship between the two fossil groups are described for the first time. The shells of dead ammonoids sank to the sea bottom and became colonized by the coral larvae, as documented by the location of the epibionts on only one side of the shells. The coral was fixed to the ammonoid shell for its entire life. Only the "sediment free" upper side of the ammonoid shells could be inhabited by epibionts such as corals and serpulids. The encrustation of ammonoid shells by the bivalve Placunopsis represents a different situation in that both sides of the ammonoid shells were affected, pointing to encrustation of floating ammonoids. This long-term infestation in the water column contrasts with coral settlement on the sea-floor. Ammonoid specimens encrusted by Placunopsis never exhibit encrustation by corals. The ammonoid-coral relationship from the Dolomites is documented from the Valanginian to Aptian interval. Examples of coral epibionts on ammonoids and other fossil groups throughout the geological column are briefly reviewed.

7

The Triassic-Jurassic transition in Asturias (northern Spain): ammonoids, bivalves and palynomorphs

Barrón E., Gómez J., Goy A., Márquez-Aliaga A.

Volumina Jurassica

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2006

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Vol. 4, no. 1

275-276

EN

A study of the Triassic/Jurassic transition in Asturias (northern Spain) was performed studying 5 surface sections and 2 boreholes (Fig. 1). Four lithological units were differentiated and correlated. The lower unit is composed of lutites and evaporites (equivalent to the Upper Triassic Keuper facies). The middle unit, which contains the Triassic/Jurassic boundary, corresponds to the well-bedded carbonates of the Solis Member of the Gijon Formation (Fig. 2). The upper unit (Barzana Member) is composed of lutites, evaporites and carbonates. The Fabares Member, overlying or representing a time equivalent of the Barzana Member is composed of a carbonate breccia with a lutitic matrix, formed by the dissolution and the collapse of the Barzana Member. The finding of ammonoids and bivalves in the Solis Member allowed refinement of the biostratigraphy and chronostratigraphy of the Rhaetian and the Hettangian. Among the ammonoids, the record of an (?)Arcestidae (Rhaetian) and several Psiloceras (such as Caloceras pirondii (Reyn?s) of the Hettangian, Planorbis Zone, in the upper part of the Solís Member can be stand out. The dominant Rhaetian bivalves are Isocyprina concentrica and Bakevellia praecursor, which together with Isocyprina ewaldi, "Pteromorphus" elongatus, Pteromya longportensis, "Placunopsis" cf. alpina, Modiolus minimus and Paleocardita cf. austriaca, represent a similar assemblage to that found in the Westbury and Lilstok formations of the Late Rhaetian age of the UK. The Hettangian bivalves are represented by the widely distributed species Pteromya tatei, associated with Cuneigervillia rhombica, Parallelodon hettangiensis and Eomiodos menkei. This assemblage is known in the Hettangian Planorbis Zone of France and Germany. The palynological study allowed identification of 20 spores taxa, 24 pollen taxa, 1 acritarch, 2 prasinophytes and 2 dinoflagellate cyst. Three palynological assemblages (PA) have been distinguished. PA1 is typically Rhaetian and corresponds to the Rhaetipollis germanicus Zone. It is characterized by the presence of Corollina meyeriana, Rhaetipollis germanicus, Ovalipollis pseudoalatus and Tsugaepollenites pseudomassulae. PA2, identified in the Solis Member, is dominated by Corollina pollen grains together with a few spores taxa, acritachs and prasinophytes and can be Rhaetian and/or Hettangian in age. PA3 represented in the upper part of Solis Member and in the Barzana Member contains Hettangian pollen assemblages characterized by Corollina meyeriana, C. torosa, Kraeuselisporites reissingeri, Ischyosporites variegatus and Cerebropollenites thiergartii. Both PA2 and PA3 can be related to the Kraeuselisporites reissingeri Zone. The palynology of the Asturian sections can reasonably be correlated with that of St. Audrie's Bay (UK).

8

Visean and Bashkirian ammonoids from Central Iran

Hairapetian V., Korn D., Bahrami A.

Acta Geologica Polonica

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2006

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Vol. 56, no. 3

229-240

EN

Two successions of Carboniferous sedimentary rocks in Central Iran yielded ammonoid assemblages from one horizon each. In the Ramsheh section, a siltstone with Neoglyphioceras yazdii n. sp. and Dombarites can be assigned to the latest Visean. The assemblage from the Shesh Angosht Mountain is more diverse with species of the genera Proshumardites, Eumorphoceras, Homoceras, Glaphyrites, Syngastrioceras, and Dombarocanites. This is the first time that the co-occurrence of the genera Eumorphoceras and Homoceras has been recorded. This fauna contains elements of the South Urals and Central Asian occurrences of Bashkirian ammonoids and suggests close palaeobiogeographic relationships.

9

A new record of Beneckeia tenuis (Seebach, 1857) from the Rhaetian of Piekoszów (Holy Cross Mountains)

Salamon M.A., Nizicki R.

Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

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2004

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T. 30, z. 4

439-444

EN

The ammonoid Beneckeia tenuis (Seebach) is recorded from the Rhaetian (Lower Anisian) of the Holy Cross Mountains. Three specimens were collected from a single rock layer that is typical of epicontinental sea deposition of the time.

PL

Opisano amonity Beneckeia tenuis (Seebach) z retu (dolny anizyk) Gór Świętokrzyskich. Charakteryzowana fauna obejmuje trzy okazy typowo epikontynentalnej formy Beneckeia tenuis, które pochodzą z jednej warstwy skalnej.

10

The Olcostephanus Level : an Upper Valanginian ammonoid mass-occurrence (Lowel Cretaceous, Northern Calcareous Alps, Austria)

Lukeneder A.

Acta Geologica Polonica

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2004

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Vol. 54, no. 1

23-33

EN

The Early Cretaceous mass-occurrence of Olcostephanus (Olcostephanus) guebhardi morph. querolensis BULOT from the Late Valanginian Saynoceras verrucosum Zone of the KB1-A section, Ternberg Nappe, the Northern Calcareous Alps (Upper Austria) is described. This horizon, spanning an interval of almost 3 metres, is interpreted as a long-term accumulation from the water column combined with temporary redeposition from local submarine highs. The fauna of the Olcostephanus horizon is composed of nine genera and ten species. The Olcostephanus mass-occurrence represents a widespread phenomenon. It appears most commonly at oceanographic elevations where olcostephanid shells accumulated on the sea-floor during see-level highs.

11

Upper Albian to Lower Cenomanian biostratigraphy in the Oyubari area, Hokkaido, Japan : toward a Cretaceous biochronology for the North Pacific

Kawabe F.

Acta Geologica Polonica

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2003

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Vol. 53, nr 2

81-91

EN

An integrated planktonic foraminifer and ammonoid biostratigraphy for the Oyubari area, Japan, provides new insights into the late Albian to early Cenomanian biochronology of the North Pacific province. The following foraminifers extend Tethyan zonation to the Oyubari area: Biticinella breggiensis (lower Upper Albian), Rotalipora subticinensis - Rotalipora ticinensis (middle Upper Albian), Rotalipora appenninica (upper Upper Albian), and Rotalipora globotruncanoides (Lower Cenomanian) zones. Co-occuring age-indicative ammonoids such as Mortoniceras rostratum, Mariella bergeri, and Mantelliceras saxbii, are in accord with these foraminifer ages. The base of the Cenomanian stage in Hokkaido is recognized as the first occurrence of Rotalipora globotruncanoides, which is close to the horizon of the occurrence of Mantelliceras. The first occurrence of Desmoceras (Pseudohligella) japonicum, regarded as a Cenomanian marker species in the North Pacific province, is of latest Albian age in the global biochronological scale.

12

Revision of stratigraphic ranges of selected invertebrate taxa from the Muschelkalk in Silesia

Niedźwiedzki R.

Geological Quarterly

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2002

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Vol. 46, No 2

219-234

EN

New occurrences of some invertebrates in the Silesian Muschelkalk are presented, hanging the stratigraphic ranges of these taxa, especially in the Dziewkowice Formation. 13 taxa have been found for the first time in this formation or had their stratigraphic ranges revised in the last two decades.

13

Morphometric evolution and phylogeny of Palaeozoic ammonoids. Early and Middle Devonian

Korn D.

Acta Geologica Polonica

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2001

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Vol. 51, nr 3

193-215

EN

A combination of methods from cladistics and stratophenetic analyses is used for a reconstruction of Early and Middle Devonian ammonoid phylogeny. The analyses are based mainly on principal characters such as conch geometry (coiling form, whorl expansion rate, whorl cross-section shape), septal geometry (form of septa, number, position, and shapes of lobes), and ornament (growth lines and ribs); a new classification scheme of the ancient ammonoid order Agoniatitida is proposed. It is subdivided into four suborders: Agoniatitina (paraphyletic), Gephuroceratina (monophyletic), Anarcestina (paraphyletic), and Pharciceratina (monophyletic). Morphometric analysis shows the unfolding of several morphological trends, such as the modification of coiling parameters, among the Early and Middle Devonian ammonoids. Two major independent lineages can be recognised in the phylogeny of the Middle Devonian ammonoids, the first represents the agoniatids in which the Gephuroceratina is nested, the second are the anarcestids which gave rise to the Pharciceratina. The new families Latanarcestidae, Tamaritidae, Atlantoceratidae, and Taouzitidae, as well as the new genera Taouzites, Croyites and Meragoniatites are introduced.

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Revision of ammonoid biostratigraphy in the Frasnian (Upper Devonian) of the Southern Timan (Northeast Russian Platform)

Becker R.

Acta Geologica Polonica

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2000

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Vol. 50, no. 1

67-97

EN

New field work in outcrops of the Ukhta Region (Southern Timan) together with the re-exanimation of former collections allows a detailed revision of the ammonoid zonation in one of the classical Frasnian regions of Russia. There is a total of 47 species, 18 of which are new or recorded for the first time from the region. The latter applies to representatives of Linguatornoceras, Phoenixites, Aulatornoceras s.str. and Acanthoclymenia. New taxa are Chutoceras manticoides n. gen. n. sp. and Linguatornoceras yudinae n. sp. In the Ust'yarega Formation regional Hoeninghausia nalivkini, Timanites keyserlingi and Komioceras stuckenbergi Zones can be recognized which correlate with the international Frasnian divisions UD I-B/C. The Ponticeras domanicense Zone (UD I-E)occupies most of the Lower Domanik, the Nordiceras timanicum Zone (UD I-F to I-H) is developed in the Middle and Upper Domanik. Following a poorly defined and short interval which rare Carinoceras, pelagic sequences of the Lyaiol Formation (Members 2-4) fall in the Virginoceras ljaschenkoae and Manticoceras lyaiolense Zones (UD I-I/J). Late Frasnian deposits (UD I-K/L) have not yielded any ammonoids so far. Correlation betwen the new zonation and the conodont zonation (Montagne Noire zones) is provided.

15

Mantle expansion upon the conch in the Late Devonian ammonoid Erfoudites

Korn D.

Acta Geologica Polonica

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2000

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Vol. 50, no. 1

21-27

EN

Specimens of the Late Devonian ammonoid species Erfoudites rugosus sp. nov. from the Rhenish Massif of Germany show an additional wrinkled structure that covers the body chamber ornament. The pattern closely resembles the dorsal wrinkle layer known from many ammonoids; the course af the wrinkles is radial, partially following the growth line course. This wrinkle structure is interpreted as resulting from a secretion of the mantle, which expanded ventrally or dorsally over the conch

16

Devonian conodont and ammonoid succession of the eastern Tafilalt (Ouidane Chebbi section), Anti-Atlas, Morocco

Belka Z.

Acta Geologica Polonica

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1999

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Vol. 49, no. 1

1-23

EN

Devonian conodonts and ammonoids occurring in association in the Ouidane Chebbi section of the eastern Tafilalt (Anti-Atlas, Morocco) are described and analysed in terms of stratigraphy. The excellently exposed sequence spans the entire Devonian; it includes open-marine carbonates and shales deposited outside the tropical realm. Except for its Middle Devonian part, the Ouidance Chebbi section is not condensed. Although the sequence was only sampled in a preliminary fashion, most of it lithological units have been dated with some precision. The study is an attempt to enhance the precision in the correlation between the Devonian conodont and ammonoid sequences. Graphic correlation method was used for estimating the precise position of the zonal and stage boundaries for the Middle and Upper Devonian intervals. The stratigraphy of the Lower Devonian at Ouidane Chebbi is still poorly defined. The Eifelian/Givetian boundary is well constrained, especially by both conodonts and ammonoids. It occurs within the uppermost part of the Kacak Event-Level, a characteristic shale horizon that beginsin the ensensis Zone and ranges into the hemiansatus Zone. Biostratigraphic indications from conodonts show that the top of the Pharciceras limestone unit is located within the norrisi Zone and the Givetian/Frasnian boundary should be placed within the characteristic black styliolinites level of the Frasne Event. The onset of the Kellwasser facies falls within the Zone 12 (winchelli Zone) of the Frasnian and it extends into the rhomboidea Zone. The combined evidence from ammonoid and trilobite data suggests that the marine deposition persisted at Ouidane Chebbi at least up to the time of the Upper praesulcata Zone.