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1
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Siliceous sponges from the Upper Cretaceous of Poland. Part 1. Tetraxonia

100%
Hurcewicz H.
Acta Palaeontologica Polonica
|
1966
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tom 11
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nr 1
Sixty two species of sponges, belonging to the Tetraxonia, of this number, 19 new ones: Brochodora latiramea n .sp., Pachypoterion biedai n.sp., Homalodora skrainivensis n.sp., H. polonica n.sp., H. brachiramosa n.sp., Heterostinia phytoniformis n.sp., Heloraphinia chordata n.sp., Phymatella irregularis n.sp., Thecosiphonia gracilis n.sp., Kozlowskispongia bulbosa n.gen., n.sp., Phyllodermia magna n.sp., Ph. pulchra n.sp., Eustrobilus extraneus n.sp., Ragadinia foraminifera n.sp., Plinthosella elegans n.sp., Acrochordonia regularis n.sp. and A. bifurcata n.sp. are described and one new genus, Kozlowskispongia n.gen., is erected. The species investigated belong to Tetractinellida (2 species), Tetracladina (32 species), Megacladina (16 species) and Dicranocladina (7 species). In most species, the morphology of the body, the structure of the skeleton and the morphology of the megascleres have been studied. In many of them, the microscleres have been found.
2
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Pleistocene burrows in the Mar del Plata area [Argentina] and their probable builders

84%
Vizcaino S. F., Zarate M., Bargo M. S., Dondas A.
Acta Palaeontologica Polonica
|
2001
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tom 46
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nr 2
Structures discovered near Mar del Plata are attributed to palaeoburrows built by fossil animals on the basis of morphological patterns, transgressive boundaries in relation to the sedimentary units, and the presence of claw marks on the walls and roofs. They are discrete features of several metres in length, and with subrounded cross sections. Their diameters range from 0.80 to 1.80 m, with the width generally exceeding the height. These structures occur in Pleistocene deposits containing mammals referable to the Ensenadan and Lujanian Ages. Several Xenarthra are good candidates as builders of these burrows. Palaeoburrows were attributed before to the large Pleistocene armadillos Propraopus, Eutatus, and Pampatherium. We consider the possibility that the mylodontid ground sloths were responsible for excavating the burrows. The similar diameters of the burrows and the sloths are consistent with this observation. Anatomical, allometric, and biomechanical analysis of sloths limbs indicates that they were well designed to perfonn such activity. The shape of some claw marks preserved on the sides and roof of the burrows fits the form of their hand skeleton. Thus, the mylodontid sloths Scelidotherium and Glossotherium are considered as possible builders for the large late Cenozoic burrows present in the Pampean region.
3

Mammals as palaeoecological indicators

67%
Andrews P.
Acta Zoologica Cracoviensia
|
1995
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tom 38
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nr 1
4
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Hydrodynamically controlled anagenetic evolution of Famennian goniatites from Poland

67%
Niechwedowicz M., Trammer J.
Acta Palaeontologica Polonica
|
2007
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tom 52
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nr 1
This paper reports on the evolution of ammonoids belonging to the family Tornoceratidae from the Devonian of Janczyce in the Holy Cross Mountains, Poland. Steady and gradual changes in conch morphology of the goniatite lineage Phoenixites frechi–Tornoceras subacutum–T. sublentiforme occurred in concert with water shallowing during the deposition of the Lower Famennian cephalopod limestone. Biometric analysis of ammonoid conch and facies analysis of the cephalopod limestones have been applied to assess the possible relationship between shell geometry and environmental changes. Results show that ratios of whorl width / diameter as well as whorl width / whorl height decreased, while distance from the venter to the greatest whorl width / diameter increased with time, thereby reducing hydrodynamic drag of the shells, probably in response to increasing water turbulence. The interpretation presented here is in agreement with similar cases from the literature. However, this kind of environmentally controlled evolution has hitherto been recognized only in Jurassic and Cretaceous ammonoids. Conch morphology may be considered as an indicator of palaeobathymetry.
5
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Piggyback whorls: A new theoretical morphologic model reveals constructional linkages among morphological characters in ammonoids

67%
Ubukata T., Tanabe K., Shigeta Y., Maeda H., Mapes R. H.
Acta Palaeontologica Polonica
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2008
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tom 53
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nr 1
A new theoretical morphological model is proposed for the analysis of growth, form and morphospace of ammonoid shells. In this model, the shape of a radial cross section through the shell is simulated by “piggybacking” of successive whorls. The “piggyback whorls model” is defined in terms of the enlarging rate of the perimeter and the proportion of the dorsal wall to the whorl periphery, if an isometric relationship is assumed between perimeter and area of the cross−sectioned whorl. Allometric coefficients on these growth parameters determine how compressed and evolute shells are formed. The present model successfully reproduced some correlations among purely geometric variables that have been reported in previous works and were also observed in our biometric analyses. This model yields a hypothesis of “constructional linkages” between aperture shape and coiling geometry that might provide a functional coupling between hydrostatic and hydrodynamic characters. The model may partly explain Buckman’s Law of Covariation between rib features and shell shapes.
6

II Sympozjum Sekcji Owadów Kopalnych Polskiego Towarzystwa Entomologicznego w Mogilanach koło Krakowa (21-22 III 1986)

59%
Koteja J.
Wiadomości Entomologiczne
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1988-1989
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tom 08
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nr 1-2
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