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Palaeoecology of corals and stromatoporoids in a Late Silurian biostrome in Estonia

100%

Kershaw S., Motus M.-A.

Acta Palaeontologica Polonica

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2016

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tom 61

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nr 1

A middle Ludlow biostrome at Katri, western Estonia, the richest accumulation of corals and stromatoporoids in Estonia, is partly exposed in a coastal section. The fully marine biostrome consists of five fossiliferous layers of carbonate skeletons, grouped into Facies 1 (grainstone-packstone, Layers 1, 3, 5) and Facies 2 (wackestone, interbedded Layers 2, 4). Pressure solution degraded original sedimentary relationships and morphologies of stromatoporoids, tabulates and rugosans which constructed the biostrome, but the two facies have major faunal differences. Facies 1 is rich in stromatoporoids “Stromatopora” bekkeri and Plectostroma scaniense (low to high domical up to ca. 30 cm in basal length); and tabulate Favosites forbesi (bulbous to high domical up to ca. 25 cm wide). In Facies 2, all three taxa are less common and much smaller. Instead, the most abundant stromatoporoid is laminar Syringostromella borealis up to 30 cm basal length; the most abundant coral is erect branching Laceripora cribrosa, as scattered fragments up to 24 cm long. Neither occurs in Facies 1. Six other stromatoporoid taxa, 5 other tabulate and 5 rugosan taxa occur uncommonly in the biostrome, mostly in both facies. The Katri biostrome is slightly younger than, but facially similar to biostromes in the middle Ludlow Hemse Group on Gotland ca. 250 km WSW, with well-known stromatoporoid faunas. Corals are abundant in Hemse biostromes. Several key stromatoporoids occur in both the Hemse biostromes and Katri, but two abundant taxa in Hemse biostromes are absent in Katri and two tabulate corals abundant in Katri are missing in Hemse biostromes. Thus there was a wide distribution of such biostromes in the central Baltic large shallow marine carbonate platform, but with previously unreported variable assemblages presumed due to facies features not recognised in the sediments.

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Astrorhizae-like structures on epitheca of rugose corals from the Carboniferous of Laos

100%

Hung N. H.

Acta Palaeontologica Polonica

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2001

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tom 46

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nr 4

Stellate patterns, called astrorhizae, occurring in some Paleozoic stromatoporoids are by most authors regarded as integral elements of these enigmatic fossils. The finding of stellate structures on epithecae of rugose corals from the Lower Carboniferous of Central Laos seems to support, however, the idea that astrorhizae in Paleozoic stromatoporoids may represent traces of foreign organisms.

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Late Famennian stromatoporoids from Debnik Anticline, southern Poland

80%

Wolniewicz P.

Acta Palaeontologica Polonica

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2009

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tom 54

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nr 2

337-350

Famennian Stromatoporoidea from the Quasiendothyra communis Foraminiferal Zone and slightly younger strata from the Dębnik anticline, southern Poland, form a succession of three consecutive assemblages. Assemblages 1 and 3 consist of representatives of the order Clathrodictyida, while assemblage 2 is dominated by the order Labechiida. The clathrodictyids are represented by the genus Gerronostroma, and labechiids are represented by the genus Stylostroma. Species assigned here to the genus Gerronostroma show a network of amalgamated pillars in the central part of the columns, a feature regarded by previous authors as typical of the genus Clavidictyon. Two new species, Stylostroma multiformis sp. nov. and Gerronostroma raclaviense sp. nov., are described. Stromatoporoids from southern Poland differ from the Famennian fauna of western Europe, showing affinity to eastern European and Siberian Stromatoporoidea.

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A giant boring in a Silurian stromatoporoid analysed by computer tomography

80%

Beuck L., Wisshak M., Munnecke A., Freiwald A.

Acta Palaeontologica Polonica

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2008

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tom 53

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nr 1

This study describes the largest known Palaeozoic boring trace, Osprioneides kampto igen. et isp. nov., found within a stromatoporoid Densastroma pexisum from the Upper Visby Formation (lower Wenlock, Silurian) on the island of Gotland, Sweden. Differences between the physical properties of the stromatoporoid and the dense micritic infilling of the borings allowed the application of the CT−scan technology for the 2D and 3D−visualisation of this rare trace. The additional application of a stereoscopic technique on these CT images and movies enhances its value for unravelling spatial orientations. This non−destructive method has a great potential for future macroas well as microboring analyses. The trace maker, most likely a worm, infested the hosting colony post−mortem with up to 120 mm long borings measuring 5–17 mm in diameter. Smaller forms of Trypanites and Palaeosabella within the same stromatoporoid preferentially occur in the outer coenosteum and occasionally in abandoned borings of O. kampto. The stratigraphic position of O. kampto follows the “Great Ordovician Biodiversification Event” in time, and reflects the increase in diversity of boring species. Borings with penetration depths of 120 mm are, however, unique findings for the Palaeozoic and were not exceeded until some 260 million years later (Bajocian, Middle Jurassic) when the “Mesozoic Marine Revolution” led to convergent reinventions as a result of enhanced predation, grazing pressure, and ecospace competition.

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Revised classification and terminology of Palaeozoic stromatoporoids

70%

Stearn C. W., Webby B. D., Nestor H., Stock C. W.

Acta Palaeontologica Polonica

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1999

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tom 44

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nr 1

Palaeozoic stromatoporoids comprise an extinct class of non-spiculate poriferans that are represented as fossils by their basal carbonate skeleton. A revised terminology for the description of these fossils is presented. Seven orders (Labechiida, Clathrodictyida, Actinostromatida, Stromatoporellida, Stromatoporida, Syringostromatida, Amphiporida) are recognized. The following is recorded for each genus: (1) type species, catalogue number and depository of the primary holotype; (2) synonyms and their type species; (3) diagnosis; (4) stratigraphic range; (5) estimate of the number of species assigned to the genus; (6) stratigraphic and geographic distribution of the genus. Problems in the definition and recognition of the genus are briefly discussed in annotations. One hundred and nine genera are considered valid, or doubtfully valid. Fifty three genera are placed in synonymy. An additional 14 genera are considered to be of uncertain placement in the classification.

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Stromatoporoids from a Middle Devonian reef in South China and their palaeoecological implication

61%

Huang J., Liang K., Wang Y., Kershaw S., Jeon J., Li Y., Qie W.

Acta Palaeontologica Polonica

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2022

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tom 67

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nr 3

Ograniczanie wyników

6 Acta Palaeontologica Polonica

2 Kershaw S.

1 Beuck L.

1 Freiwald A.

1 Huang J.

1 Hung N. H.

1 Jeon J.

1 Li Y.

1 Liang K.

1 Motus M.-A.

1 Munnecke A.

1 Nestor H.

1 Qie W.

1 Stearn C. W.

1 Stock C. W.

1 Wang Y.

1 Webby B. D.

1 Wisshak M.

1 Wolniewicz P.

1 2022

1 2016

1 2009

1 2008

1 2001

1 1999

Palaeoecology of corals and stromatoporoids in a Late Silurian biostrome in Estonia

Astrorhizae-like structures on epitheca of rugose corals from the Carboniferous of Laos

Late Famennian stromatoporoids from Debnik Anticline, southern Poland

A giant boring in a Silurian stromatoporoid analysed by computer tomography

Revised classification and terminology of Palaeozoic stromatoporoids

Stromatoporoids from a Middle Devonian reef in South China and their palaeoecological implication