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1

Zespół skamieniałości a biocenoza - reprezentatywność zapisu paleontologicznego

100%

Niedźwiedzki R.

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tom Vol. 50, nr 10/1

899-904

PL

Podczas przeobrażania się biocenozy w oryktocenozę największe znaczenie mają czynniki oddziaływujące na nekrocenozę, zwłaszcza rozkład organizmów bezszkieletowych, w rezultacie którego w tafocenozie nie zachowuje się przeciętnie od ok. 70% gatunków (w środowiskach morskich) do ponad 90% gatunków (w środowiskach lądowych) występujących w biocenozie. Wśród zwierząt szkieletowych podstawowymi czynnikami działającymi na etapie nekrocenozy jest dysartykulacja i fizyczne, chemiczne lub biologiczne niszczenie szkieletów. Procesy te działają często selektywnie w zależności od przynależności taksonomicznej, a także od wielkości okazów i niekiedy uniemożliwiają odtworzenie liczebności taksonów. Bardzo istotne jest uśrednianie czasowe, które zachodzi zarówno w obrębie nekrocenozy, jak i tafocenozy. Zjawisko to powoduje nadreprezentację wielu taksonów oraz niemożność obserwowania krótkoterminowych zmian biocenozy. Po utworzeniu się tafocenozy zachodzą dalsze zmiany zespołu skamieniałości, m.in. w wyniku rozpuszczania szkieletów aragonitowych oraz pokryw chitynowych. Dlatego w artykule używam terminu "oryktocenoza" dla zespołów skamieniałości zachowanych do czasów współczesnych.

EN

Most important for post-mortem modification of biocoenosis structure are processes which influenced the necrocoenosis, especially nonpreservation of soft-bodied organisms. This factor alone may eliminate from about 70% species in marine environments to more than 90% species in terrestrial environments. Shelly communities are changed post-mortem mainly by disarticulation and by physical, chemical or biological destruction. These factors are strongly selective and their importance depend on taxonomic position and size of specimens. Such processes can seriously hamper the recognition of abundance of specimens and proportions of taxa. Time-averaging is very important for modification both the necrocoenosis and the taphocoenosis. The consequences of this phenomenon are preservational bias favouring some taxa of the taphocoenosis and the fact, that short-term biologic phenomena are extremely rarely observed in the fossil assemblages. Many kind of taphocoenosis modifications are documented, e.g., dissolution of aragonite shells or chitinous integuments. Therefore, I use the term " orictocoenosis "for assemblages of fossil remains preserved to our times.

2

New paleontological data from the Turonian and Coniacian of the Opole Trough (SW Poland)

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Niedźwiedzki R. , Godlewska A.

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tom Vol. 37

27-33

EN

This report is on the first Micrabaciidae (Micrabacia sp.) solitary corals to have been found in the Upper Cretaceous deposits of the Opole Trough. We also present descriptions of the first nautilids (Cymatoceras sp.; smooth-shelled Nautilidae), regular echinoids (Gauthieria radiata (Sorignet, 1850) and solitary corals (Parasmilia sp.) to have been found in the Lower Coniacian of the Opole region.

3

Late Cretaceous sharks in the Opole Silesia region (SW Poland)

63%

Niedźwiedzki R. , Kalina M.

Geologia Sudetica

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2003

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tom Vol. 35

13-24

EN

The upper Cretaceous deposits of the Opole Trough contain rare but relatively diverse shark teeth, mainly from ptychodontid sharks (Ptychodus latissimus Agassiz, 1843, Ptychodus polygyrus Agassiz, 1843 and Ptychodus mammillaris Agassiz, 1843), Anacoracidae (Squalicorax sp.), Mitsukurinidae (Scapanorhynchus raphiodon (Agassiz, 1843)), Alopiidae (Paranomotodon angustidens (Reuss 1845)) and Cretoxyrhinidae. Paranomotodon angustidens has not previously been reported from the Opole Trough. The selachians from the Opole Basin can be divided into two trophic groups: bottom-dwelling ptychodontid sharks with a diet consisting of shelly invertebrates, and pelagic Lamniformes, which were active predators feeding on fast-swimming fish and reptiles. The morphology of the teeth, signs of abrasion and the analysis of the invertebrate assemblage from the Opole Cretaceous suggest that the ptychodontids fed on inoceramid bivalves, while the lamniform sharks fed mostly on fish. Lamniformes live in all marine environments, and their remains are numerous in all the lithostratigraphic units of the Upper Cretaceous in the Opole Trough. The teeth of deep-water ptychodontid sharks are only abundant in the middle part of the Middle Turonian sediments. Nearshore shark remains are extremely rare in the Cretaceous deposits of the Opole Trough. This indicates that the Middle Turonian (middle I. lamarcki Zone) represents the deepest environment of the Opole Cenomanian and Turonian .

4

A new ceratite record from Upper Silesia (Poland)

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Salamon M. , Eagle M. K. , Niedźwiedzki R.

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tom Vol. 47, No 3

281-288

EN

A new ceratite locality from Gołuchowice (Upper Silesia, Poland) is described. Ceratites from the spinosus group found there include Ceratites (Acanthoceratites) cf. praespinosus, found for the first time in Upper Silesia. Five ceratite zones are proposed for that region: pulcher, robustus, compressus, evolutus and spinosus. The taxonomic compositions of individual ceratite zones from Upper Silesia are almost identical to those of corresponding zones from the Holy Cross Mountains. However, ceratite zones in Poland show lower taxonomic diversity than their equivalents in Germany.

5

Oxygen isotope analysis of shark teeth phosphates from Bartonian (Eocene) deposits in Mangyshlak peninsula, Kazakhstan

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Pelc A. , Hałas S. , Niedźwiedzki R.

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tom Vol. 42, iss. 1

53--61

EN

We report the results of high-precision (±0.05‰) oxygen isotope analysis of phosphates in 6 teeth of fossil sharks from the Mangyshlak peninsula. This precision was achieved by the offline preparation of CO2 which was then analyzed on a dual-inlet and triple-collector IRMS. The teeth samples were separated from Middle- and Late Bartonian sediments cropping out in two locations, Usak and Kuilus. Seawater temperatures calculated from the δ18O data vary from 23–41oC. However, these temperatures are probably overestimated due to freshwater inflow. The data point at higher temperature in the Late Bartonian than in the Middle Bartonian and suggest differences in the depth habitats of the shark species studied.

6

Age, distribution, and phylogeny of the peculiar Late Devonian ammonoid Soliclymenia

51%

Korn D. , Niedźwiedzki R. , Posieczek J.

Acta Geologica Polonica

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2005

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tom Vol. 55, no. 2

99-108

EN

New records of the triangularly coiled Soliclymenia paradoxa (MUNSTER, 1839) from Dzikowiec (Sudetes, Poland) allow the study of intraspecific variability. It can be demonstrated that at least three species within the genus Soliclymenia can be separated. The genus has a limited stratigraphic distribution within the .Wocklumeria Stufe. of the Late Devonian, but a wide geographic range within the tropical seas.