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Gastropod succession across the Early-Middle Frasnian transition in the Holy Cross Mountains, southern Poland

100%

Krawczynski W.

Acta Palaeontologica Polonica

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2006

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tom 51

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nr 4

679-693

Gastropod response to a marked carbon isotopic geochemical anomaly across the Early–Middle Frasnian transition (Palmatolepis transitans–Palmatolepis punctata conodont zones) has been analysed along the southern Laurussian shelf, mainly within the Dyminy Reef in the Holy Cross Mountains. Gastropods are represented by three reefal associations (Kowalatrochus sanctacrucensis, Euryzone kielcensis, and Grabinopsis guerichi associations), and an impoverished open−shelf Straparollus laevis assemblage. The most severe diversity crisis is connected to the disappearance of local low−energy muddy habitats, as a result of a transgressive pulse (Middlesex Event) and benthic habitat changes tied to strongly fluctuating carbon cycling; this has been observed at the highly diverse Kadzielnia−type assemblage. Fifteen taxa have been recognised in this distinctive Early Frasnian mud−mound association, including six (probably endemics), which are unknown from the Middle Frasnian. The disappearance of three relict Givetian species (Euryzone delphinuloides, Straparollus laevis, and Goniasma? zarecznyi) is also recorded. Other species probably migrated into the shallower water part of Dyminy Reef and persisted in the Middle and Late Frasnian. The Middlesex Event and the earlier major biogeochemical perturbation seem to have less serious effects for evolution of gastropods in the Polish−Moravian part of the Laurussia shelf than the catastrophic Frasnian–Famennian extinction. Two new taxa are described: Frydiella kaimi gen. et sp. nov. (Eotomariidae) and Heidelbergeria czarnieckii gen. et sp. nov. (Elasmonematidae).

2

Frasnian gastropod synecology and bio-events in the Dyminy reef complex of the Holy Cross Mountains, Poland

100%

Krawczynski W.

Acta Palaeontologica Polonica

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2002

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tom 47

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nr 2

Late Frasnian–Early Famennian entomozoacean ostracod assemblages from the Płucki section in the Holy Cross Mountains were studied to establish the effect of the “Kellwasser bio−event” on the planktonic biodiversity and faunal content. The composition of ostracod assemblages changes from a moderately diverse (10 species) Entomoprimitia–Richterina– Nehdentomis–Nandania dominated “background” assemblage characterising a pre−event interval, to an Entomoprimitia−assemblage during the event interval, and finally to a Franklinella−dominated post−event assemblage in the Middle Palmatolepis triangularis conodont Zone. The Frasnian–Famennian extinction caused substantial losses among entomozoacean lineages. In the Płucki section it occurred in two closely spaced steps within the Palmatolepis linguiformis conodont Zone. The first step, at the base of the dark cephalopod limestone (Upper Kellwasser Horizon), reduced the abundance and the species diversity of entomozoaceans to only two Entomoprimitia species. The vacant niche was then filled by the new, immigrant species Entomoprimitia (Entomoprimitia) kayseri which is dominant in the Upper Kellwasser interval. All these species were lost at the second step within the Upper Kellwasser Horizon. The entomozoaceans remained virtually absent during a long time interval between the end−Frasnian crisis and the Middle Pa. triangularis Zone. They reappear as new species from refugia lineages (Franklinella, Nehdentomis) and became widespread, indicating favourable ecological conditions. Some 13 species have been identified and assigned to seven genera. Rabienella? lagowiensis sp. nov. is proposed.

3

Westphalian xiphosurans [ Chelicerata ] from the Upper Silesia Coal Basin of Sosnowiec, Poland

63%

Filipiak P., Krawczynski W.

Acta Palaeontologica Polonica

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1996

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tom 41

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nr 4

413-425

The xiphosurans Bellinurus lunatus (Martin, 1809) and Euproops rotundatus (Prestwich, 1840) are described from sideritic concretions hosted by the Orzesze Beds (Westphalian B) in. the Polish region of the Upper Silesia Coal Basin. Associated flora and fauna include terrestrial plant remains and a single palaeodictyopteran insect nymph. As no marine influences are known in this area since the Namurian A, these xiphosurans were probably fresh-water organisms.

4

Molluscs from the Early Frasnian goniatite level at Kostomloty in the Holy Cross Mountains, Poland

51%

Jagt-Yazykova E., Krawczynski W., Rakocinski M.

Acta Palaeontologica Polonica

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2006

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tom 51

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nr 4

707-718

The unique goniatite−rich pyritic level, 1.6 m thick, exposed at Kostomłoty (Holy Cross Mountains, central Poland) represents a distinct, local biotic event in the Early Frasnian interval corresponding to the inception of a major geochemical (carbon cycling) perturbation in the stagnant deep−water and oxygen−deficient Kostomłoty basin. The taxonomic and palaeoecologic characteristics of molluscan fossil associations from the Goniatite Level are presented. Most of the goniatitids and orthoconic nautiloids from the studied fossil assemblages are juvenile conchs or protoconchs, or incomplete phragmocones and represent the genera Acanthoclymenia and Linguatornoceras, the former being predominant, and a single adult specimen probably of the genus Koenenites. In contrast, gastropods and bivalves are generally well preserved and identifiable to species level. Two new species are described: a gastropod Palaeozygopleura (Bohemozyga) pyritica sp. nov. and a bivalve Glyptohallicardia multicostata sp. nov. These studied molluscs and also amphiporoids are allochthonous elements which must have been transported into the deeper settings during sea−level rise and flooding of fringing reefs (Timan Event) and/or storm events, and there were mixed with pelagic cephalopods. Probably, a sea−level rise even led to flooding of nearby areas, and thus to introduction of pelagic material (juvenile cephalopods) into reefal settings, and then back to the deeper water again by the quasi−estuarine circulation of water masses.

Ograniczanie wyników

4 Acta Palaeontologica Polonica

4 Krawczynski W.

1 Filipiak P.

1 Jagt-Yazykova E.

1 Rakocinski M.

2 2006

1 2002

1 1996

Gastropod succession across the Early-Middle Frasnian transition in the Holy Cross Mountains, southern Poland

Frasnian gastropod synecology and bio-events in the Dyminy reef complex of the Holy Cross Mountains, Poland

Westphalian xiphosurans [ Chelicerata ] from the Upper Silesia Coal Basin of Sosnowiec, Poland

Molluscs from the Early Frasnian goniatite level at Kostomloty in the Holy Cross Mountains, Poland