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1

Silurian rugose coral Schlotheimophyllum Smith, 1945 from the Upper Visby Beds of Gotland, Sweden

Wrzołek Tomasz, Zatoń Michał

Annales Societatis Geologorum Poloniae

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2023

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Vol. 93, No. 3

251--267

EN

A rich (about 60 specimens) collection of Schlotheimophyllum, large rugose corals from the Silurian of Gotland, Sweden, was studied. Although the material is mostly fragmentary (beach pebbles), the presence of growth lines, clearly seen in thin sections, provides reliable numerical data. Analyzed were corallum shape, septal numbers, and aspects of coloniality. Uniformity of variability spectra of these parameters indicates that all of the material studied belongs to a single, variable species, which is Schlotheimophyllum patellatum (Schlotheim, 1820).

2

Lower Carboniferous solitary rugose corals from the Flett Formation of the Liard Basin, northwestern Canada vs. European and Asian Rugosa of the same geological age

Chwieduk Edward

Acta Geologica Polonica

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2022

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Vol. 72, no. 1

33--88

EN

The paper focuses on the taxonomic description of the lower Carboniferous (uppermost Tournaisian to middle Viséan) solitary rugose corals from bedded limestone and shale units in the Flett Formation in the Jackfish Gap (eastern Liard Range), northwestern Canada. The corals described herein include 12 species representing the genera Ankhelasma Sando, 1961, Bradyphyllum Grabau, 1928, Caninophyllum Lewis, 1929, Cyathaxonia Michelin, 1847, Ekvasophyllum Parks, 1951, EnniskilleniaKabakovich in Soshkina et al., 1962, Vesiculophyllum Easton, 1944 and Zaphrentites Hudson, 1941. Two of these species are new (Ankhelasma canadense sp. nov. and Ekvasophyllum variabilis sp. nov.) and 6 taxa are described in open nomenclature. The distribution and relative abundance of solitary Rugosa in Europe and the Liard Basin confirm the geographical proximity of those areas and the open marine communication between them during the early Carboniferous. It therefore represents an important contribution to the determination of the time of isolation of the western Laurussia shelf fauna from that of southeastern Laurussia, as well as the time of the possible emergence of species from southeastern Laurussia into the western Laurussia seas. Of particular importance here are cosmopolitan taxa and the timing of their disappearance from the fossil record.

3

Bashkirian Rugosa (Anthozoa) from the Donets Basin (Ukraine). Part 10. The Family Krynkaphyllidae fam. nov.

Fedorowski Jerzy

Acta Geologica Polonica

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2021

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Vol. 71, no. 1

53--101

EN

The known occurrence of corals distinguished here in the new Family Krynkaphyllidae varies at the subfamily level. Those of the Subfamily Krynkaphyllinae subfam. nov. are so far almost unknown from outside of the Donets Basin. In contrast, those of the Subfamily Colligophyllinae subfam. nov. are common, possibly ranging from the lower Viséan Dorlodotia Salée, 1920, a potential ancestor of the family, to the Artinskian Lytvophyllum tschernovi Soshkina, 1925. They bear different generic names, but were all originally described as fasciculate colonial. A detailed study of Lytvophyllum dobroljubovae Vassilyuk, 1960, the type species of Colligophyllum gen. nov., challenges that recognition in that at least some of those taxa are solitary and gregarious and/or protocolonial. As such, solitary, protocolonial and, probably, fasciculate colonial habits are accepted in the Colligophyllinae subfam. nov., whereas the Krynkaphyllinae subfam. nov. contains only solitary taxa. The resemblance to the Suborder Lonsdaleiina Spasskiy, 1974 led to the analysis of families included in that suborder by Hill (1981) in the context of their relationship, or homeomorphy, to Krynkaphyllidae fam. nov. This question primarily concerns the Family Petalaxidae Fomichev, 1953; a relationship with the Family Geyerophyllidae Minato, 1955, is more distant, if one exists. The distinct, parallel stratigraphic successions of taxa within two subfamilies of the Krynkaphyllidae fam. nov. document their probably common roots and early divergence. However, a lack of robust data precludes an interpretation or treatment of those successions as phylogenetic. The absence of key stratigraphic and morphologic data meant that eastern Asiatic taxa have not been considered in these successions; however, morphological similarities allow for their tentative inclusion within the Krynkaphyllidae fam. nov. The following new taxa are introduced: Krynkaphyllidae fam. nov., Krynkaphyllinae subfam. nov., Colligophyllinae subfam. nov., Krynkaphyllum gen. nov., Colligophyllum gen. nov., Protokionophyllum feninoense sp. nov., Krynkaphyllum multiplexum sp. nov., Krynkaphyllum validum sp. nov., and three species of Protokionophyllum Vassilyuk in Aizenverg et al., 1983 left in open nomenclature.

4

Bashkirian Rugosa (Anthozoa) from the Donets Basin (Ukraine). Part 8. The Family Kumpanophyllidae Fomichev, 1953

Fedorowski Jerzy

Acta Geologica Polonica

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2019

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Vol. 69, no. 3

431--463

EN

The Family Kumpanophyllidae Fomichev, 1953, synonymised by Hill (1981) with the Family Aulophyllidae Dybowski, 1873, is emended and accepted as valid. The new concept of this family, based on both new collections and discussion on literature data, confirms the solitary growth form of its type genus Kumpanophyllum Fomichev, 1953. However, several fasciculate colonial taxa, so far assigned to various families, may belong to this family as well. The emended genus Kumpanophyllum forms a widely distributed taxon, present in Eastern and Western Europe and in Asia. Its Serpukhovian and Bashkirian occurrences in China vs Bashkirian occurrences in the Donets Basin and in Spain, may suggest its far-Asiatic origin, but none of the existing taxa can be suggested as ancestral for that genus. Thus, the suborder position of the Kumpanophyllidae remains unknown. Four new species: K. columellatum, K. decessum, K. levis, and K. praecox, three Kumpanophyllum species left in open nomenclature and one offsetting specimen, questionably assigned to the genus, are described.

5

Bashkirian Rugosa (Anthozoa) from the Donets Basin (Ukraine). Part 9. The Subfamily Dirimiinae, subfam. nov.

Fedorowski Jerzy, Ohar Victor V.

Acta Geologica Polonica

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2019

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Vol. 69, no. 4

583--616

EN

A new Subfamily Dirimiinae of the Family Kumpanophyllidae Fomichev, 1953 is introduced on the basis of Dirimia gen. nov., which is represented by six new named species and three species left in open nomenclature. The new species are Dirimia multiplexa, D. similis, D. recessia, D. composita, D. extrema, D. nana, Dirimia sp. 1, Dirimia sp. 2 and Dirimia sp. 3. The progressing atrophy of the columnotheca, leading to its total reduction in extreme species, and the occurrence of an axial structure instead of a compact pseudocolumella established in these species are accepted as differences exceeding the genus level. All specimens assigned to this subfamily were derived from the same Limestone F1 of the Donets Basin, and mostly from the same locality. The reasons for their split into a relatively large number of species are: 1) an increased radiation typical for faunal turnover times; 2) a delay in the appearance of differentiated skeletal characters relative to the appearance of genetic differences large enough to characterise different species; 3) a bias in preservation of fossil remnants by comparison to living populations, amplified by biases in the collections available for study by comparison to the total number of specimens fossilised.

6

Tournaisian and Viséan Lophophyllum of Gorskiy (1932) from the Kirghiz Steppe and a possible ancestor of a new Bashkirian rugose coral genus from the Donets Basin (Ukraine)

Fedorowski J.

Geologos

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2017

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Vol. 23, No. 3

215--221

EN

All specimens assigned by Gorskiy (1932) to the genus Lophophyllum Milne Edwards and Haime, 1850 are revised, redescribed and reillustrated. The corallite identified by him as a second, specifically indeterminate species of Lophophyllum is here questionably included in Amygdalophyllum Dun and Benson, 1920. For the reminding specimens two new, unnamed genera are suggested. ”Lophophyllum” subtortuosum Gorskiy, 1932 belongs to a new, non-dissepimented genus of an unknown family. A possible relationship between gen. nov. 1, sp. nov. 1 and the new Bashkirian genus from the Donets Basin (Ukraine) is proposed.

7

Early Bashkirian Rugosa (Anthozoa) from the Donets Basin (Ukraine). Part 6. The Family Aulophyllidae Dybowski, 1873

Fedorowski J.

Acta Geologica Polonica

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2017

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Vol. 67, no. 4

459--514

EN

Seven genera (one new), belonging to four subfamilies, seven named species (six new), four species left in open nomenclature and two specimens included in this paper as unnamed Aulophyllidae are described from strata ranging from the lowermost Bashkirian Limestone D510 to the lower Bashkirian Limestone F1. A new genus: Voragoaxum and six new species: Dibunophyllum medium, Dibunophylloides columnatus, D. paulus, D. similis, Voragoaxum cavum and Rozkowskia lenta are introduced. Comparison of the ontogeny of the earliest Bashkirian species of Nina Fedorowski, 2017a and Dibunophylloides Fomichev, 1953 suggest the derivation by descent of the Family Bothrophyllidae from the Subfamily Dibunophyllinae. This means that true bothrophylla are absent in the Mississippian strata of the Western European Province and, perhaps, in the contemporaneous strata of other areas as well.

8

Serpukhovian (Early Carboniferous) Rugosa (Anthozoa) from the Lublin Basin, eastern PolandSerpukhovian (Early Carboniferous) Rugosa (Anthozoa) from the Lublin Basin, eastern Poland

Fedorowski J.

Annales Societatis Geologorum Poloniae

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2015

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Vol. 85, No. 1

221--270

EN

Sixteen rugose coral species, two known previously, nine new, three left in open nomenclature, and two identified as affinis, are described from the early Serpukhovian strata of the Lublin area, eastern Poland. Rugose corals of that age here are described for the first time from Poland. New genera include Birkenmajerites, Chelmia and Occulogermen. New species include: Axisvacuus tenerus, Birkenmajerites primus, Chelmia radiata, Nervophyllum lukoviensis, Occulogermen luciae, Rotiphyllum plumeum, Sochkineophyllum symmetricum, Zaphrentites rotiphylloides and, Zaphrufimia anceps. A brief analysis of the taphonomy, possible relationships and geographical connections of the corals described here to rugose coral faunas from adjacent areas also is included.

9

Rugosa (Anthozoa) of the Serpukhovian Lower Carboniferous) of the Upper Silesian Coal Basin

Fedorowski J., Machłajewska I.

Acta Geologica Polonica

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2014

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Vol. 64, no. 1

13--45

EN

Two species, Antiphyllum sp. nov. 1 and Zaphrufimia sp. nov. 1, the first corals found in Štur horizon of the upper Malinowickie Beds, Upper Pendleian (E1), are here described. Additional study of the subspecies of Zaprufimia disjuncta show them to be more similar than previously thought. Although they occur mainly in the Enna and Barbara horizons, one specimen of Z. d. serotina comes from the Gabriela horizon. Biozone Zaphrufimia disujncta disjuncta/Z .d. praematura is proposed for the Enna and Barbara horizons. The subzone of Zaphrufimia/Triadufimia of that Biozone, defined by the presence of Triadufimia gen. nov., is restricted to the Enna horizon. As confirmed by the occurrence of Cravenoceratoides edalensis, the new subzone roughly corresponds to the E2b1 ammonite Zone. An Antiphyllum/Ostravaia/Variaxon assemblage Zone is proposed for the coral assemblage of the Gaebler horizon. Cravenoceratoides nitidus present in the Roemer band (Ib) shows it to correlate with the E2b2 ammonite Zone. Comparison with other European regions suggests possible faunal exchange between those areas and the Upper Silesian Coal Basin in Serpukhovian time.

10

Some peculiar rugose coral taxa from Upper Serpukhovian strata of the Czech Republic

Fedorowski J.

Acta Geologica Polonica

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2010

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Vol. 60, no. 2

165-198

EN

Two genera from Upper Serpukhovian strata in the Czech Republic part of the Silesian Coal Basin are described and figured. Ostravaia gen. nov., included in Ostravaiainae subfam. nov., may belong to the Family Antiphyllidae Ilina, 1970. It is represented by one, morphologically variable new species, O. silesiaca. Two other species, conditionally included in that genus, are left in open nomenclature. Variaxon gen. nov., included in Variaxoninae subfam nov. of an undetermined family, is represented by two species, one of which, V. radians, is new.

11

Early Permian solitary rugose corals from Kruseryggen (Treskelodden Fm., Hornsund area, southern Spitsbergen)

Chwieduk Edward

Geologos

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2009

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Vol. 15, No. 1

57--75

EN

A collection of solitary rugose corals collected from the Treskelodden Formation of the Kruseryggen Hill, Hornsund area, south Spitsbergen, consists of 30 specimens representing the Bothrophyllidae family with the genera Bothrophyllum, Caninophyllum, Hornsundia, and Timania (5 species), and an indeterminate family with the genus Svalbardphyllum (one species). These large, dissepimental forms, dating from the Early Sakmarian (Tastubian), indicate a warm-water environment. The lithology, the thickness of the succession, the reddish hue and the abrasion of the fossils indicate that the area of the inner Hornsund showed a relief that enabled considerable erosion of the elevated areas and redeposition of the fossils at remote locations. The changing morphology of this area during the Early Permian was probably influenced by synsedimentary block tectonics.

12

Early Bashkirian Rugosa (Anthozoa) from the Donets Basin, Ukraine. Part 2, On the genera Axisvacuus gen. nov. and Falsiamplexus Fedorowski, 1987

Fedorowski J.

Acta Geologica Polonica

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2009

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Vol. 59, no. 3

283-317

EN

Five species belonging to two genera: Falsiamplexus Fedorowski, 1987 and Axisvacuus gen. nov. are described in detail and their species content and relationships are discussed. Both genera are perhaps related to Rotiphyllum and were probably derived from it, but relationship of Falsiamplexus to Bradyphyllum Grabau, 1928 cannot be excluded. The new genus Axisvacuus is represented by four species, of which three are new: A. verus (type species), A. extendus and A. semicirculatus. Stratigraphic ranges of species described are compared to the western European and Russian standards (Table 1). Some possible palaeogeographic implications of the occurrence of Axisvacuus postumus (Smith, 1931) and Falsiamplexus reductus Fedorowski, 1987 are briefly discussed.

13

Early Bashkirian Rugosa (Anthozoa) from the Donets Basin, Ukraine. Part 1, Introductory considerations and the genus Rotiphyllum Hudson, 1942

Fedorowski J.

Acta Geologica Polonica

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2009

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Vol. 59, no. 1

1-37

EN

The present paper is the first in a series devoted to the Early Bashkirian Rugosa (Anthozoa) from the Donets Basin. The history of investigation and current status of Early Bashkirian stratigraphy is discussed in the context of the Donets Basin strata. Corals of that time interval are extremely rare worldwide and those from the Donets Basin have never been described in detail. Four of the five species described are new: Rotiphyllum asymmetricum sp. nov., R. latithecatum sp. nov., R. simulatum sp. nov., and R. voznesenkae sp. nov. Two species are left in open nomenclature. The synonymy, species content and critical review of species potentially belonging to the genus Rotiphyllum are reviewed.

14

Early Carboniferous Chinese and Australian „Siphonodendron” (Anthozoa, Rugosa): ecological and geographical influenceon taxonomy

Fedorowski Jerzy

Geologos

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2008

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Vol. 14, No. 1

3--17

EN

Normal marine salinity is the main limiting factor for the Subclass Rugosa. Water depth and temperature are less critical. Individual characteristics of specimens and some characteristics of species are, however, excel-lent environmental indicators. Being distributed exclusively by larvae, Rugosa required free distribution by means of marine currents, as well as midway areas suitable for settlement and metamorphosis of the larvae. Not distance but rather geography and midway environments are therefore the limiting factors for their distribution, relationships and stratigraphic value. Siphonodendron and Siphonodendron-like (“Siphonodendron”) corals are discussed as examples of morphoogical similarity, but not necessarily representing a phylogenetic relationship. The known homeomorphy of European and western North American Siphonodendron taxa (Fedorowski & Bamber 2007) may be extended on the European, some southern Chinese and all south-eastern Australian Siphonodendron-like corals, but only the Chinese and SE Australian forms may be truly related. The latter relationship would extend the boundaries of the Early Carboniferous Australian rugose coral province. The Late Tournaisian age of the earliest Australian “siphonodendrons” indicates an ancestry of the coral fauna within the province (SE Australia and S China).A mechanism for north-westward migration of this fauna, from SE Australia to S China, is not clear.

PL

Normalne zasolenie mórz stanowi główny czynnik ograniczający występowanie podgromady Rugosa. Głębokość i temperatura wody są mniej istotne. Tym niemniej, poszczególne cechy okazów i niektóre cechy gatunkowe są doskonałymi wskaźnikami środowiska. Rugosa rozprzestrzeniały się wyłącznie w stadium larwalnym. Kolonizacja nowych obszarów była zatem związana z istnieniem otwartej komunikacji morskiej, odpowiednio ukierunkowanych prądów, a w przypadku długich dystansów również z istnieniem pośrednich obszarów dogodnych dla osiadania i metamorfozy larw. Tak więc nie odległość jako taka, lecz układ lądów i mórz oraz warunki ekologiczne na obszarach pośrednich były czynnikami ograniczającymi dla rozprzestrzenienia, pokrewieństw i wartości stratygraficznej Rugosa. Właściwy rodzaj Siphonodendron i koralowce podobne do tego rodzaju („sifonodendrony”) zostały w tym artykule przedyskutowane jako przykład podobieństwa morfologicznego, ale niekoniecznie pokrewieństw filogenetycznych. Homeomorfia europejskich i północno-amerykańskich taksonów (Fedorowski & Bamber2007) może zostać przeniesiona również na europejskie oraz niektóre chińskie i wszystkie australijskie „sifo-nodendrony”. Tylko gatunki z ostatnich dwóch obszarów mogą być rzeczywiście spokrewnione. Pokrewieństwo to rozszerzyłoby granice wczesnokarbońskiej prowincji australijskiej (SE Australia i S Chiny). Późnoturnejski wiek najstarszych „sifonodendronów” australijskich wskazuje na ich pozycję wyjściową w obrębie prowincji. Mechanizm rozprzestrzeniania się tych faun ku północnemu zachodowi, z SE Australii do S Chin, pozostaje niejasny.

15

Late Devonian and early Carboniferous Rugosa from Western Pomerania, northern Poland

Chwieduk E.

Acta Geologica Polonica

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2005

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Vol. 55, no. 4

393-443

EN

The taxonomic description of the Late Devonian and Early Carboniferous Rugosa from the boundary area of the Precambrian East European Craton and the Palaeozoic platform of Central Europe is presented. Palaeontological analysis and the stratigraphical distribution of the corals in Western Pomerania enabled recognition of several faunistic events, which reflect evolutionary trends in rugose corals. The pre-crisis Frasnian coral fauna, dominated by colonial forms, both massive [Disphyllia laxa] (GÜRICH, 1896), [Hexagonaria hexagona kowalae] (WRZOŁEK, 1992), ?Frechastraea] and branching [Disphyllum kweihsiense YOH, 1937,Peneckiella ?fascicularis (SOSHKINA, 1952), [Thamnophyllum monozonatum] (SOSHKINA, 1939), [Peneckiella szulczewskii] (RÓŻKOWSKA, 1979), developed on the carbonate platform extending along the edge of the East European Craton. The similarity of these faunas to Rugosan faunas from southern Poland is significant. The coral fauna was reduced significantly after the Kellwasser crisis. Colonial corals disappeared altogether and solitary dissepimented forms were markedly reduced. The subsequent Late Famennian radiation caused a significant quantitative and qualitative differentiation of the coral faunas. In addition to the well-known "Cyathaxonia fauna", warm and shallow-water solitary corals appeared in the latest Famennian. The stratigraphically important taxa of the latest Famennian include: [Campophyllum] (MILNE-EDWARDS & HAIM, 1850), [Palaeosmilia aquisgranense] (FRECH, 1885), [Bounophyllum pomeranicum sp. nov.] and [Guerichiphyllum kowalense] (RÓŻKOWSKA, 1969). The latest Famennian regression caused subdivision of the Pomeranian area into at least two sedimentary basins, separated by shallows, with peculiar ecological conditions, and the appearance of numerous endemic taxa. This regressive interval contains, however, numerous levels yielding less restricted faunas, which suggest the intermittent appearance of more open-sea conditions.

16

Some remarks on diagenesis of rugose coral skeletons

Fedorowski Jerzy

Geologos

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2003

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Vol. 6

89--110

EN

Rugose coral microstructure exhibits striking similarity to that in the Scleractinia. The main difference lies in the mineral composition: calcitic in the former and aragonitic in the latter. Calcitic skeletons of the Rugosa are commonly better preserved than those in the Scleractinia, and therefore some of them have been interpreted as unaltered, a position rejected in this paper. The dual nature of septa, which commonly consist of a primary trabecular septum and secondary fibrous sheets, results in differently expressed diagenetic alterations in comparison to other structural elements. It has been postulated that both early and advanced diagenesis may, in some circumstances, be distinguished in the Rugosa. In most instances the early diagenetic features were destroyed by the post-burial alterations. Replacement and recrystallization are the most important processes among the advanced chemical alterations. Both may either facilitate the recognition of original macro- and microstructures or obscure them. Surface replacement by silica promotes perfect preservation of shape and inner morphology, whereas pervasive replacement may destroy both. Selected replacement by hematite may help in exposing the trabecular microstructure of septa, whereas deep replacement may destroy the entire morphology. Physical alterations, such as crushing and flattening of skeletons are always destructive. They result from compaction, and their scale depends on skeletal morphology and on the relationship between the rate of infilling of intra-skeletal spaces and the accumulation of surrounding sediment. Pre-burial events, such as overgrowth and penetration by borrowing organisms, their holdfasts or roots may aid in the recognition of early diagenesis, but may also lead to substantial pre- or post-burial skeletal alteration, resulting sometimes in total destruction. This depends mostly on the pH of pore fluids.

17

Permian Waagenophyllidae of Vietnam

Khoa Nguyen Duc

Geologos

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1999

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Vol. 4

47--100

EN

Twenty species belonging to ten waagenophyllid genera were described. The following species are new: Waagenophyllum (W.) choaiense, Ipciphyllum baho- nense, Parawentzelella canalifera langnacensis, Wentzelophyllum densicolumnatum and W. ipciphylloides. Laophyllum huulungensis Khoa, 1980 and Pseudohungia hatienensis Khoa, 1984 were re-studied and supplemented. Representatives of Huayunophyllum, Szechuanophyllum, and Wentzelophyllum were described for the first time from Vietnam. Waagenophyllidae appeard in Vietnam in the Asselian Schwagerina Biozone and became extinct near the top of the Changhsingian Palaeofusulina sinensis Biozone. Some differences between southern and northern Vietnamese coral faunas may have resulted from their development on the opposite shelves of the Indochinese microcontinent. Those differences are rather slight and both faunas belong to the Tethys Realm.

PL

Wapienie są dominującymi osadami w permo-karbonie północnego i południowego Wietnamu. Terrygeniczne, skrzemionkowane osady z wkładkami wapieni pojawiają się na tych obszarach dopiero w górnym permie. Tylko w środkowej części Wietnamu przeważają osady terrygeniczne. W osadach permskich wydzielono 8 biozon otwornicowych (Tabela I). Waagenophyllidae pojawiły się w Wietnamie w asselu (biozona Schwagerina), a wymarły przed końcem changhsingu (biozona Palaeofusulina). Szczytowy rozwój osiągnęły w środkowym permie (biozony Misellina do Lepidolina-Yabeina). W późnym permie przedstawiciele tej rodziny znani są obecnie jedynie z masywów Bac Son w północnym Wietnamie i Hon Quan w Wietnamie południowym. Waagenophyllidae są najbardziej zróżnicowaną rodzajowo rodziną wśród permskich Rugo- sa Wietnamu. W niniejszej pracy opisano 20 gatunków z 10 rodzajów i podrodzajów, w tym 4 nowe gatunki: Waagenophyllum (Waagenophyllum) chobaiense, Ipciphyllum bahonense, Wentze- lophyllum densicolumnatum, Wentzelophyllum ipciphylloides i 1 nowy podgatunek: Parawentzelel- la canalifera langnacensis. Uzupełniono również badania i opisy Pseudohuangia hatienensis Khoa i Iranophyllum (Laophyllum) huulungense Khoa. Rodzaje Waagenophyllum i Ipciphyllum są najbardziej zróżnicowane gatunkowo. Tworzą one zespół faunistyczny charakterystyczny dla środkowego permu. Rozprzestrzenienie geograficzne poszczególnych taksonów Waagenophyllidae jest zróżnicowane. W południowym Wietnamie nie znaleziono dotychczas form osobniczych, natomiast licznie występują formy kolonijne, zwłaszcza masywne.

18

Permian corals of the Cordilleran-Arctic-Uralian Realm

Fedorowski J., Bamber E., Stevens C.

Acta Geologica Polonica

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1999

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Vol. 49, no. 2

159-173

EN

Permian rugose corals of the Cordilleran-Arctic-Uralian Realm are abundant in shallow-water carbonates along the northwestern and western margin of Pangaea, from the Ural Mountains, area in Russia, through the Svalbard Archipelago and arctic and western North America, to Bolivia and Peru. The colonial forms are of particular interest for the biostratigraphy and reconstruction of the paleogeography of this extensive region. A revision of the systematics of these corals has shown that, although important differences exist between the assemblages in the areas listed, the faunas are recognizable throughout the entire realm. Almost all of the faunas in the realm, on cratonal Pangaea, are Cisuralian (Asselian to Artinskian) in age although younger faunas occur in rocks of terranes subsequently accreted to North America. The cratonal faunas show a general trend from a predominance of relatively simple, fasciculate species with open axial areas or weakly developed axial structures in the lowest Permian, to younger, more complex fasciculate and massive species with a variety of morphological elements in their axial structures and dissepimentaria. Suppression of the walls occurs commonly in the youngest faunas. As a result of the northward movement of Pangaea into cooler waters, colonial rugose corals were exterminated from the more northerly areas by early to mid-Artinskian time, but persisted throughout the Artinskian and possibly into the Kungurian and early Guagalupian in the cratonic successions of the western U.S.A. Similarities between the coral faunas of cratonal North America and the western allochthonous terranes indicate that faunal interchange occurred between these various coral faunas during the Cisuralian. The only colonial corals recovered from Wordian to Lopingian rocks in this region are waagenophyllid corals of tethyan affinity from the Cache Creek and Quesnellia terranes of British Columbia and the Hayfork and Eastern Klamath terranes of California.