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On Cretaceous Stephanocyathus (Scleractinia) from the Tatra Mts.

100%

Stolarski J.

Acta Palaeontologica Polonica

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1990

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tom 35

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nr 1-2

2

Gardineria - a scleractinian living fossil

100%

Stolarski J.

Acta Palaeontologica Polonica

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1996

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tom 41

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nr 4

339-367

The basic architecture (Bauplan) and microstructure of the skeleton of Recent Gardineria are noticeably different from those of most other modern scleractinians. The wall of the Gardineria skeleton is entirely epithecate (non-trabecular), while in the majority of modern Scleractinia the epitheca is either absent or added to the main wall which usually is of trabecular nature. These different patterns of theca formation reflect significant anatomical differences in the peripheral parts of the polyp. The Bauplan of Gardineria pattern, exceptional in the modern scleractinian fauna, was widespread among early Mesozoic corals, particularly among the Triassic protoheterastraeids. Similar skeletons also occur in some late Palaeozoic rugosans (e.g., polycoeliids). Zardinophyllum zardini, an aberrant Triassic scleractinian coral, with a supposed rugosan septal insertion, supports the hypothesis of the rugosan origin of the Scleractinia

3

Ontogenetic development of the thecal structures in caryophylliine scleractinian corals

100%

Stolarski J.

Acta Palaeontologica Polonica

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1995

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tom 40

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nr 1

19-44

At the initial stage of ontogeny, in Caryophylliidae (Miocene Caryophyllia salinaria, C. depauperata, Recent C. berteriana) and Flabellidae (Miocene Flabellum roissyanum Recent Jauania cailleti), wall and septa are formed simultaneously, and their trabecular structure is coalesced (marginothecal wall). At subsequent juvenile stage in Caryophylliidae the presence of the extensive exosarc enables formation of costo-septa and, in consequence, formation of trabeculotheca. Trabeculotheca consists of fragments of primordial wall located between the costosepta. The trabeculothecal segments vanish in the adult stage in the majority of corals when the septothecal wall is formed by thickening of the costo-septa. In others, however, marginotheca can be present throughout the whole ontogenetic sequence (C. salinaria). Most Flabellidae are characterized by limited expression of exosarc and the presence of marginothecal wall up to the adult stage. The origin of 'flabellid' organization in Caryophylliina may result from a simple modification of ontogeny - extention of initial morphology to later ontogenetic stages. Such corals could develop several times, and the Flabellidae may be polyphyletic

4

Transverse division in a Miocene scleractinian coral

100%

Stolarski J.

Acta Palaeontologica Polonica

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1991

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tom 36

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nr 4

Specimens of ‘Discotrochusʼ duncani, at various stages of transverse division occur abundantly in the Miocene Korytnica clays in the Holy Cross Mountains, Poland. This mode of asexual reproduction probably predominated in the studied population, and is here put forward as an adaptation for rapid colonization of soft bottoms. Truncatocyathus gen. n. is proposed to include ‘D.’ duncani.

5

Three-dimensional micro- and nanostructural characteristics of the scleractinian coral skeleton: A biocalcification proxy

100%

Stolarski J.

Acta Palaeontologica Polonica

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2003

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tom 48

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nr 4

The contemporary “two−step model” of growth of the scleractinian skeleton is based mostly on transversely sectioned samples. According to this model, many skeletal elements e.g., septa are formed in two temporally distinct phases represented by (1) “centers of calcification” that are composed of homogenously distributed microcrystalline or/and organic components and serve as scaffolding for the further growth of (2) fibrous skeleton. Based on transverse and longitudinal sections and histochemical staining techniques, I demonstrate herein that in extant corals (i.e., Stephanocyathus, Flabellum, Desmophyllum, “Ceratotrochus”, Galaxea, Platygyra), the entire septal skeleton is composed of superimposed layers of mineral and organic−enriched phases. These may be interrupted in some directions of growth but in other directions there is continuity between “centers of calcification” and “fibers”, making any distinction between these two structures unclear. As an alternative to the “two−step model”, a “layered model” of skeletal growth is proposed, that explains the differences between “centers of calcification” and “fibers” in terms of differential growth dynamics between these regions. Instead of the traditional but inadequate “trabecular” and “centers of calcification” concepts, a distinction between deposits of the Rapid Accretion Front (dRAF; which in particular cases can be organized into Centers of Rapid Accretion (CRA), and Thickening Deposits (TD) is proposed. In the dRAF region, mineral components, ca. 50 nm in diameter, seem to match the size range of nodular structures recently interpreted as nascent CaCO₃ crystals. Remarkable regularity of the mineral/organic phase alternations (microbanding) in the TD skeleton of zooxanthellate corals and lack of such regular microbanding in azooxanthellate coralla is a promising criterion for distinguishing these two ecological coral groups on a skeletal basis, and one that could be applicable to fossils.

6

Shell biomineralization rate in freshwater bivalves of the genus Unio in natural environment experimental measurements of short-term dynamics of shell growth

63%

Skawina A., Stolarski J.

Folia Malacologica

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2013

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tom 21

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nr 3

7

Nanostructure of biogenic versus abiogenic calcium carbonate crystals

63%

Stolarski J., Mazur M.

Acta Palaeontologica Polonica

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2005

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tom 50

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nr 4

847-865

The mineral phase of the aragonite skeletal fibers of extant scleractinians (Favia, Goniastrea) examined with Atomic Force Microscope (AFM) consists entirely of grains ca. 50–100 nm in diameter separated from each other by spaces of a few nanometers. A similar pattern of nanograin arrangement was observed in basal calcite skeleton of extant calcareous sponges (Petrobiona) and aragonitic extant stylasterid coralla (Adelopora). Aragonite fibers of the fossil scleractinians: Neogene Paracyathus (Korytnica, Poland), Cretaceous Rennensismilia (Gosau, Austria), Trochocyathus (Black Hills, South Dakota, USA), Jurassic Isastraea (Ostromice, Poland), and unidentified Triassic tropiastraeid (Alpe di Specie, Italy) are also nanogranular, though boundaries between individual grains occasionally are not well resolved. On the other hand, in diagenetically altered coralla (fibrous skeleton beside aragonite bears distinct calcite signals) of the Triassic corals from Alakir Cay, Turkey (Pachysolenia), a typical nanogranular pattern is not recognizable. Also aragonite crystals produced synthetically in sterile environment did not exhibit a nanogranular pattern. Unexpectedly, nanograins were recognized in some crystals of sparry calcite regarded as abiotically precipitated. Our findings support the idea that nanogranular organization of calcium carbonate fibers is not, per se, evidence of their biogenic versus abiogenic origin or their aragonitic versus calcitic composition but rather, a feature of CaCO₃ formed in an aqueous solution in the presence of organic molecules that control nanograin formation. Consistent orientation of crystalographic axes of polycrystalline skeletal fibers in extant or fossil coralla, suggests that nanograins are monocrystalline and crystallographically ordered (at least after deposition). A distinctly granular versus an unresolvable pattern of nano−organization of CaCO₃ fibers seems to correspond, respectively, to an original versus a diagenetically depleted amount of organic matter bounding a mineral phase; this is consistent with qualitative and quantitative analyses of organic matter content in extant and fossil skeletons.

8

Swiadectwa triasowego pochodzenia amfiastreidow [koralowce szesciopromienne]

63%

Roniewicz E., Stolarski J.

Działalność Naukowa PAN. Wybrane Zagadnienia

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2003

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tom 15

50-53

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Evolutionary trends in the epithecate scleractinian corals

63%

Roniewicz E., Stolarski J.

Acta Palaeontologica Polonica

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1999

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tom 44

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nr 2

131-166

Adult stages of wall ontogeny of fossil and Recent scleractinians show that epitheca was the prevailing type of wall in Triassic and Jurassic corals. Since the Late Cretaceous the frequency of epithecal walls during adult stages has decreased. In the ontogeny of Recent epithecate corals, epitheca either persists from the protocorallite to the adult stage, or is replaced in post-initial stages by trabecular walls that are often accompanied by extra-calicular skeletal elements. The former condition means that the polyp initially lacks the edge zone, the latter condition means that the edge zone develops later in coral ontogeny. Five principal patterns in wall ontogeny of fossil and Recent Scleractinia are distinguished and provide the framework for discrimination of the four main stages (grades) of evolutionary development of the edge-zone. The trend of increasing the edge-zone and reduction of the epitheca is particularly well represented in the history of caryophylliine corals. We suggest that development of the edge-zone is an evolutionary response to changing environment, mainly to increasing bioerosion in the Mesozoic shallow-water environments. A glossary is given of microstructural and skeletal terms used in this paper.

10

Microstructural diversity of the stylophyllid [Scleractinia] skeleton

63%

Stolarski J., Russo A.

Acta Palaeontologica Polonica

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2002

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tom 47

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nr 4

Coralla of the three species of solitary corals described herein from the Sinemurian (Lower Jurassic) of Sicily, i.e., Haimeicyclus haimei (Chapuis and Dewalque, 1853), Stylophyllopsis sp. cf. S. rugosa (Duncan and Wright, 1867), and Stylophyllopsis sp. A., conform to the overall stylophyllid morphology. Their septa consist of spines that are increasingly covered with sclerenchyme and low in the calice form compact blades. The pattern of diagenetic alteration of septa is diverse but consistent within particular taxa. It suggests that the spectrum of the original microstructures is wider than traditionally suggested for stylophyllids. In H. haimei, the septa are covered with dense granulations and completely recrystallized. Granulations also cover septal faces of Stylophyllopsis cf. rugosa and have rod−like foundations. In Stylophyllopsis sp. A., vestiges of the narrow mid−septal zone (similar to that in minitrabecular corals) occur in the proximal part of larger septa, whereas septal spines which are similar to those in Stylophyllopsis cf. rugosa occur in their distal parts. Similar diversity of microstructures is reported also in Triassic stylophyllids that have aragonitic coralla. The presence of distinct septal spines along with wide−ranging microstructural diversity of traditional Triassic–Jurassic stylophyllids, casts light on their possible evolutionary relationships, and can be a useful criterion for further revision of the group. For example, Jurassic thecocyathids, considered ancestral to caryophylliinans, share similar spiny/lobate septa with stylophyllids. Also Recent deep−water anthemiphylliids with spiny/lobate septa are strikingly similar to stylophyllids. Although this may be another example of parallel evolution, the separation of anthemiphylliids from other scleractinian clades on a mitochondrial 16S RNA tree topology suggests their ancient roots and enable us to suggest a stylophyllid ancestry. The supposed cyclic pattern of protoseptal insertion in Early Jurassic H. haimei supports the hypothesis of scleractinian−like (and not rugosan) ancestory of the stylophyllid evolutionary lineage.

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Organic components of the skeleton of scleractinian corals - evidence from in situ acridine orange staining

51%

Gautret P., Cuif J. P., Stolarski J.

Acta Palaeontologica Polonica

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2000

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tom 45

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nr 2

107-118

Scleractinian skeleton is composed of mineral and organic phases. Using staining techniques (acridine orange dye) Johnston's (1980) pioneering observations of intraskeletal organic envelopes in Pocillopora damicornis coralla can be extended to two other coral reef genera i.e., Acropora and Favia. The concept of biologically mediated growth of coral skeleton stands in opposition to the purely mineralogic concept of fiber growth of Bryan and Hill (1941) widely applied until recently in geological and paleontological literature. Presence of active mineralizing organic components within the skeleton explains various patterns of microstructural organization more accurately than the mineralogic concept of 'crystal growth competition' of Barnes (1970) alone. Biochemical degradation of intraskeletal organic matrices is considered to be involved in the initial diagenesis of coral skeleton, and may explain selective silicification of the late Cretaceous Coelosmilia sp. from Poland.

12

A model for furcate septal increase in a Triassic scleractiniamorph

51%

Stolarski J., Roniewicz E., Grycuk T.

Acta Palaeontologica Polonica

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2004

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tom 49

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nr 4

Triassic corals with septa that branch repeatedly and centripetally are here assigned to a new genus Furcophyllia. Septa of F. septafindens (Volz, 1896), re−described from the Italian Dolomites, are composed of 3–10 blades (“septal brooms”). Distances between adjacent septa and their branches are equal, and the thickness of all blades is approximately the same throughout ontogeny. However, none of the septal brooms show the same branching pattern. Proposed herein is a simple computer model that reproduces septal pattern, similar to that of Furcophyllia, based on a minimal set of rules: (i) uniform coverage of intra−calicular space; (ii) regular bifurcations following some probability; (iii) keeping some minimal distance between septal branches. The elaborate septal pattern of Furcophyllia suggests a distinct organization of the polyp’s soft tissue, especially mesenteries whose appearance in modern corals is associated with insertion of sclerosepta. Hypothesis 1 suggests that mesenterial pairs flanked only “septal brooms” and that septal branches functionally corresponded with septal microarchitecture. Hypothesis 2 suggests that mesenterial pairs developed between all septal branches that functionally correspond with conventional septa. Delicate menianae, which developed on Furcophyllia septal faces (and many other Triassic corals) resemble similar septal microarchitecture of the Recent agariciid Leptoseris fragilis and may be closely related to the suspension feeding strategy of this coral. The furcate septal arrangement in Furcophyllia is unique among Triassic corals, and generally, among Mesozoic and Cenozoic corals. The only analogous corals are Cretaceous aulastraeoporids (e.g., Preverastrea, Paronastraea), Trochoidomeandra, and some Jurassic rhipidogyrids having secondary (apophysal) septal branches. In some Recent caryophylliids (Trochocyathus rhombocolumna, Phacelocyathus flos) primary septa may also split dichotomously and centripetally.

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Antiquity of the scleractinian-sipunculan symbiosis

51%

Stolarski J., Zibrowius H., Loser H.

Acta Palaeontologica Polonica

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2001

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tom 46

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nr 3

Extant corals symbiotic with sipunculans, i.e., the caryophylliid Heterocyathus and the dendrophylliid Heteropsammia, develop corallum modifications (in comparison with 'ordinary' representatives of these families) that seem to meet the needs of the coral's worm partner. We distinguish two types of corallum modifications, designated the monoporous and the polyporous types. In the adult monoporous type, the shell inhabited by the sipunculan is usually overgrown only in part by the coral base. There are two orifices: the main one and a smaller pore in the upper part of the corallum. In the polyporous type the shell inhabited by the sipunculan is entirely overgrown and the coral produces a spiralled sipunculan housing. In addition to the main orifice there are several pores in the lower part of the corallum. Heterocyathus priscus sp. n. from the Early Cretaceous (Albian) of France is the oldest example of symbiosis, in which the monoporous-type corallum was modified in the same way as in extant monoporous Heterocyathus. We speculate that the monoporous type was ancestral, as only this type is known to occur among Cretaceous corals. Morphological similiarities between Heteropsammia and certain species of Heterocyathus, such as the Pourtalès plan of septal arrangement and skeleton porosity, may point to a close phylogenetic relationship.

14

Nanostructural and geochemical features of the Jurassic isocrinid columnal ossicles

45%

Stolarski J., Gorzelak P., Mazur M., Marrocchi Y., Meibom A.

Acta Palaeontologica Polonica

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2009

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tom 54

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nr 1

69-75

Calcite isocrinid ossicles from the Middle Jurassic (Bathonian) clays in Gnaszyn (central Poland) show perfectly preserved micro− and nanostructural details typical of diagenetically unaltered echinoderm skeleton. Stereom pores are filled with ferroan calcite cements that sealed off the skeleton from diagenetic fluids and prevented structural and geochemical alteration. In contrast with high−Mg calcite skeleton of modern, tropical echinoderms, the fossil crinoid ossicles from Gnaszyn contain only 5.0–5.3 mole% of MgCO₃. This low Mg content can be a result of either a low temperature environment (ca. 10℃) and/or low Mg/Ca seawater ratio. Both conditions have been proposed for the Middle Jurassic marine environment. Occurrence of Mg−enriched central region of stereom bars of Jurassic columnal ossicle of Chariocrinus andreae is consistent with the concept of magnesium ions involvement in earliest growth phases of calcium carbonate biominerals.

15

Sloneczna symbioza

44%

Stolarski J.

Wiedza i Życie

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1994

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nr 04

46-49

Ograniczanie wyników

On Cretaceous Stephanocyathus (Scleractinia) from the Tatra Mts.

Gardineria - a scleractinian living fossil

Ontogenetic development of the thecal structures in caryophylliine scleractinian corals

Transverse division in a Miocene scleractinian coral

Three-dimensional micro- and nanostructural characteristics of the scleractinian coral skeleton: A biocalcification proxy

Shell biomineralization rate in freshwater bivalves of the genus Unio in natural environment experimental measurements of short-term dynamics of shell growth

Nanostructure of biogenic versus abiogenic calcium carbonate crystals

Swiadectwa triasowego pochodzenia amfiastreidow [koralowce szesciopromienne]

Evolutionary trends in the epithecate scleractinian corals

Microstructural diversity of the stylophyllid [Scleractinia] skeleton

Organic components of the skeleton of scleractinian corals - evidence from in situ acridine orange staining

A model for furcate septal increase in a Triassic scleractiniamorph

Antiquity of the scleractinian-sipunculan symbiosis

Nanostructural and geochemical features of the Jurassic isocrinid columnal ossicles

Sloneczna symbioza