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1

Swiadectwa triasowego pochodzenia amfiastreidow [koralowce szesciopromienne]

100%
Roniewicz E., Stolarski J.
Działalność Naukowa PAN. Wybrane Zagadnienia
|
2003
|
tom 15
50-53
2

Kierunki ewolucyjne w rozwoju koralowcow szesciopromiennych [koralowce, parzydelkowce]

86%
Roniewicz E.
Kosmos
|
1996
|
tom 45
|
nr 4
687-700
3
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A model for furcate septal increase in a Triassic scleractiniamorph

86%
Stolarski J., Roniewicz E., Grycuk T.
Acta Palaeontologica Polonica
|
2004
|
tom 49
|
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.
4
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Antiquity of the scleractinian-sipunculan symbiosis

86%
Stolarski J., Zibrowius H., Loser H.
Acta Palaeontologica Polonica
|
2001
|
tom 46
|
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.
5
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Correction of homonymy of generic name Cyclophyllia Roniewicz, 1989 (Scleractinia) into Cycliphyllia nom. n.

72%
Roniewicz E.
Acta Palaeontologica Polonica
|
1991
|
tom 36
|
nr 2
A new generic name, Cycliphyllia, is here proposed as a replacement name for Cyclophyllia Roniewiecz, 1989 (type species: Thecosmilia cyclica Schaefer et Senowbari-Daryan, 1978, Upper Triassic). The latter is a junior homonyme of Cyclophyllia Milne-Edwards et Haime, 1848 (type species: Cyclolites cristata Lamarck, 1801, Cretaceous), an invalid name, which is a junior synonyme of Aspidiscus Koenig, 1825 (Milne-Edwards 1857: t. 2, p. 386). This regrettable error has been noticed thanks to the List of generic names by Wells (1986). As a consequence of the above change, the orthography of the family name Cyclophylliidae Roniewicz, 1989 is here corrected into Cycliphylliidae.
6
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Early Norian (Triassic) corals from the Northern Calcareous Alps, Austria, and the intra-Norian faunal turnover

58%
Roniewicz E.
Acta Palaeontologica Polonica
|
2011
|
tom 56
|
nr 2
The first description of early Norian coral fauna from the Northern Calcareous Alps (Dachstein Plateau and Gosaukamm), Austria, is presented: 31 scleractinian species from 24 genera (including three corals not formally determined), and three hexanthiniarian species belonging to two genera. The stratigraphical position of the main part of the fauna discovered in the South Dachstein Plateau at the Feisterscharte is determined by means of the conodont Epigondolella quadrata (Lacian 1); single finds are from the horizons with Epigondolella triangularis and Norigondolella navicula (Lacian 3), and one close to the horizon with Epigondolella cf. multidentata (Alaunian 1). Rare corals from the Gosaukamm are from the Lacian 1 and Alaunian. Five species are described as new: Retiophyllia vesicularis, Retiophyllia aranea, Margarosmilia adhios, Hydrasmilia laciana; one new genus and species from the family Coryphylliidae, Margarogyra hirsuta; one new genus and species, Thamnasterites astreoides, cannot be assigned to a family. Two hexanthiniarian species, Pachysolenia cylindrica and Pachydendron microthallos, known exclusively from the Tethyan lower Norian, represent stratigraphically valuable species. A regularly porous coral from the family Microsolenidae, Eocomoseris, which up to now has only been known from the Jurassic and Cretaceous, is here identified from the Triassic strata (originally described as Spongiomorpha [Hexastylopsis] ramosa). Predominant taxa show solitary and phaceloid (pseudocolonial) growth forms and an epithecal wall; pennules−bearing corals are common. Carnian genera and genera typical of the Lacian and Lacian–early Alaunian prevail; a hydrozoan genus Cassianastraea has also been encountered as well as a scleractiamorph coral, Furcophyllia septafindens). The faunal composition contrasts with that of well known late Norian–Rhaetian ones, the difference being observed not only at the generic but also at the family level. The post−early Norian change in coral spectrum documents the turnover of the coral fauna preceding that at the Triassic/Jurassic boundary.
7
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Commensalism in the fossil record: Eunicid polychaete bioerosion on Pliocene solitary corals

58%
Martinell J., Domenech R.
Acta Palaeontologica Polonica
|
2009
|
tom 54
|
nr 1
143-154
Some solitary caryophylliid (Caryophyllia, Trochocyathus, and Ceratotrochus) and flabellid (Flabellum) scleractinian corals from Pliocene of Western Mediterranean exhibit long groove−shaped bioersional structures running along the surface of the thecae. They are epigenic structures produced by an episkeletozoan and therefore, they are described as Fixichnia. Here we propose Sulcichnus as a new ichnogenus, with three new ichnospecies (Sulcichnus maeandriformis, S. helicoidalis, and S. sigillum) to name this traces. Sulcichnus is attributed to the activity of polychaetes. Similar structures are recently produced by Lumbrineris flabellicola, a symbiotic eunicid which maintains a commensalistic relationship with solitary corals. In the fossil record, Sulcichnus occurs associated to shallow marine environments whereas their Recent counterparts are described on deep−marine corals. We interpret this as a consequence of a change in the environmental requirements of the coral/worm pair.
8
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Organic components of the skeleton of scleractinian corals - evidence from in situ acridine orange staining

58%
Gautret P., Cuif J. P., Stolarski J.
Acta Palaeontologica Polonica
|
2000
|
tom 45
|
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.
9
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Evolutionary trends in the epithecate scleractinian corals

58%
Roniewicz E., Stolarski J.
Acta Palaeontologica Polonica
|
1999
|
tom 44
|
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
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Microstructural diversity of the stylophyllid [Scleractinia] skeleton

58%
Stolarski J., Russo A.
Acta Palaeontologica Polonica
|
2002
|
tom 47
|
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.
11
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Three-dimensional micro- and nanostructural characteristics of the scleractinian coral skeleton: A biocalcification proxy

58%
Stolarski J.
Acta Palaeontologica Polonica
|
2003
|
tom 48
|
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.
12
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Rugosa and Scleractinia - a commentary on some methods of phylogenetic reconstructions

58%
Fedorowski J.
Acta Palaeontologica Polonica
|
1997
|
tom 42
|
nr 3
The origin of the Rugosa and relationships between the Rugosa and Scleractinia are debated. In the present account I comment on some recently published phylogenetic reconstructions, which in my opinion, are based on inadequate data.
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