Age, distribution, and phylogeny of the peculiar Late Devonian ammonoid Soliclymenia
KORN D.1, NIEDZWIEDZKI R.2, POSIECZEK J.B.
1Museum für Naturkunde der Humboldt-Universität zu Berlin, Invalidenstraße 43, D-10115 Berlin, Germany.
dieter.korn@museum.hu-berlin.de
2Institute of Geological Sciences, Wroclaw University, pl. M. Borna 9, PL-50-205 Wroclaw, Poland.
rnied@ing.uni.wroc.pl
3Komandorska str. 65/8, Wroclaw, Poland.
dimmi5@interia.pl
ABSTRACT: New records of the triangularly coiled Soliclymenia paradoxa (MÜNSTER, 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.
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Myzostomid and copepod infestation of Jurassic echinoderms: A general approach, some new occurrences, and/or re-interpretation of previous reports
RADWANSKA U., RADWANSKI A.
Institute of Geology, Warsaw University, Al. Zwirki i Wigury 93, PL-02-089 Warszawa, Poland.
u.radwanska@ uw.edu.pl
ABSTRACT: A study of diverse cysts developed on fossil echinoderms from Poland results in the recognition that these on Late Jurassic crinoid stems are attributable to the life activity of myzostomidan polychaetes, and those on Middle and Late Jurassic echinoids, to the activity of copepod arthropods. A review of formerly reported cysts of coeval age from Europe and western Asia permits the distinguishing of several types that differ in shape and/or location on the echinoderm skeleton. Although the studied cysts qualify as trace fossils (which require a separate ichnotaxonomy), their ethological and ecological characteristics are presented in terms of interspecific parasite-host relationships. The classical interpretation of VON GRAFF (1885) is affirmed for myzostomidan endocysts in crinoid stems, whereas for echinoid tests a new interpretation is offered for large exocysts (‘Halloween pumpkin-mask’ type) as having been induced by copepods, comparable in their ethology to those on present-day biota (hydrocorals) other than echinoderms. A copepod attribution by MERCIER (1936) of cysts (Castexia type) on some Middle Jurassic collyritid echinoids from France is fully accepted. This is supplemented by some new finds in Poland, a re-study of the Castexia cysts from France, and a re-interpretation of former reports from the literature. Eco-ethological consequences of the location of copepods in the ambulacral and peristomial parts of cidaroid and hemicidaroid echinoids are discussed; larval settling apparently took place at the tubefeet pores and gonopores, through which the copepod larvae reached the echinoid’s interior and began to parasitize it. Attribution of the discussed cysts to copepods yields, consequently, an extension of the stratigraphical range of the class Copepoda H. MILNE-EDWARDS, 1840, to the Early Jurassic.In POSTSCRIPT, suggested is the bald-sea-urchin disease to have caused some lesions in the collyritid echinoids (Middle Jurassic: Callovian ) from France.
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Tectonically-controlled sedimentation of Cenozoic deposits from selected basins along the Vietnamese segment of the Red River Fault Zone
WYSOCKA A.1, SWIERCZEWSKA A.2
1Faculty of Geology, University of Warsaw, Zwirki i Wigury 93, PL-02-089 Warszawa, Poland.
Anna.Wysocka@uw.edu.pl
2Institute of Geological Sciences, Polish Academy of Sciences, Cracow Research Centre, Senacka 1, PL-31-002 Krakow.
ABSTRACT: Small, narrow sedimentary basins occur along the main faults in the Vietnamese segment of the Red River
Fault Zone (RRFZ), which is the major discontinuity separating the South China and Indochina microplates. The sedimentary basins of the RRFZ
are grouped into three main sections: along the Red River Valley, the Chay River Valley and the Lo River Valley. The sedimentary basins are
filled with thick series of Palaeogene and Neogene clastic deposits that differ in type and origin. In the lower part of the basin fill,
coarse-grained deposits predominate. In the upper part, different types of sandstones, siltstones and brown coal occur. There are no
sediments of Late Pliocene age. Quaternary deposits are represented by sands and gravels. Biostratigraphical data are very poor,
therefore only lithostratigraphical subdivision is applied. Thus, it is possible that deposits from adjacent basins associated with
the RRFZ represent strata of different ages. The investigations were focused on the Lo River Basin (associated with the Chay River fault),
Yen Bai Basin (associated with the Red River fault) and Co Tiet Basin (associated with the southwesternmost branch of the Red River fault).
Thirteen sedimentary facies were recognised in deposits filling the investigated basins. The facies were grouped into five facies
associations representing five distinct depositional environments. These comprise alluvial fan, gravel-dominated fluvial channel,
sand-dominated fluvial channel, alluvial plain and lacustrine environments. In addition, the basin fills show features characteristic
of strike-slip basins.
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First nearly complete skeleton of the Cretaceous duvaliid belemnite Conobelus
LUKENEDER A.
Natural History Museum Vienna, Department of Geology and Palaeontology, Burgring 7, A-1010, Vienna, Austria.
alexander.lukeneder@nhm-wien.ac.at
ABSTRACT: The first Cretaceous belemnite preserved with the rostrum, slightly compressed phragmocone and part of the proostracum is described from the Early Cretaceous (Late Valanginian) Rossfeld Formation (Eibeck, Reichraming Nappe of the Northern Calcareous Alps). The rostrum has dorsal groove (alveolar furrow) typical of duvaliids, and its conical shape (round in transverse section outline), and the rounded apex allow its attribution to Conobelus Stolley, 1919. The new species C. pseudoheres sp. nov. is proposed based on the unique features of the specimen, i.e. persistently parallel lateral sides throughout the rostrum and the conical, blunt outline at the apex. The ration between rostrum and phragmocone is 0.78; the distances between the calcitic septa of the anterior end of the phragmocone range from 3 to 5 mm. The proostracum is 0.02 mm thick. The apical angle is 32º and the alveolar angle (posterior end of the phragmocone) is 24º. The alveolus is 40 mm long, yielding a ratio between rostrum and alveolus of 1.86. The depositional history with its fast sedimentation along with absent/limited post-mortem transportation led to extraordinarily good preservation of the examined specimen.
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Devonian rugose corals of the Phillipsastrea hennahii species group
WRZOLEK T.
Department of Earth Sciences, University of Silesia, Bedzinska Str. 60, PL 41-200 Sosnowiec, Poland.
wrzolek@us.edu.pl
ABSTRACT: Massive phillipsastreid tetracorals similar to Phillipsastrea hennahii, defined as a Ph.
hennahii species group, are characterized by reduced intercorallite walls (thamnasterioid or subthamnasterioid habit), by variable but
generally good development of horseshoe dissepiments at the tabularium/dissepimentarium boundary, and by strongly deflected peripheral
platforms at corallite margins. Seven species of the Ph. hennahii species group, mostly from the Givetian of southern Euramerica,
Iberia and northern Gondwana, are reviewed. Two species, the Middle Givetian Phillipsastrea sobolewi (ROZKOWSKA 1956) and the
Late Givetian Phillipsastrea jachowiczi, a new species described herein, both from the Holy Cross Mountains (Poland) are described
and illustrated. Also described from that area is Phillipsastrea falsa COEN-AUBERT 1987 from the Upper Frasnian.
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Selenite-gypsum microbialite facies and sedimentary evolution of the Badenian evaporite basin of the northern Carpathian Foredeep
BABEL M.
Institute of Geology, Warsaw University, Al. Zwirki i Wigury 93, PL-02-089 Warszawa, Poland.
m.babel@uw.edu.pl
ABSTRACT: Facies analysis was applied to the six main facies of the Badenian (Middle Miocene) gypsum deposits exposed along
the margin of the Carpathian Foredeep basin, from Moldova to the Czech Republic. These facies, recognised within
primary selenite and fine-grained gypsum deposits, are: (i) selenites with vertical crystals; (ii) selenites with horizontal
crystals; (iii) selenite debris flow facies; (iv) selenite debris facies; (v) gypsum microbialite facies; and (vi) alabastrine
facies. The facies represent various environments (from shallow-brine to subaerial) of a giant salina-type basin
without open-water connections with the sea and showing evaporite drawdown. Integration of facies analysis and event
stratigraphic studies in the gypsum basin allowed reconstruction of its sedimentary history. The architecture of the gypsum
facies suggests that the margin of the basin was occupied by a system of variable perennial saline pans (dominated
by selenite deposition) and evaporite shoals (dominated by gypsum microbialite deposition). The basin was infilled
with evaporite deposits by aggradation. After initial evaporite drawdown, the northern margin of the basin evolved
from a large perennial saline pan (or system of pans) into an evaporite shoal and then back again into a perennial pan,
whereas the east area of the basin was a vast evaporite shoal dominated by gypsum microbialites. Separate selenite
pans of oligotrophic-type developed both at the periphery and in the interior of this shoal. Later, predominantly clastic
gypsum deposition developed throughout the basin margin, presumably due to a drastic change in the chemistry
and salinity of the brine. Evaporite deposition was arrested by a flood of marine waters and rapid deepening.
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