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Asteroidea from the lower Kimmeridgian of Wapienno/Bielawy, Kuyavia region, north-central Poland

Loba Michał, Radwańska Urszula

Acta Geologica Polonica

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2022

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Vol. 72, no. 1

89--106

EN

A relatively rich assemblage of starfish is recognised from the talus facies of an Upper Jurassic (lower Kimmeridgian) biohermal, sponge-cyanobacterial build-up from the Wapienno/Bielawy succession exposed in a salt-dome anticline in Kuyavia region, north-central Poland. The paper presents 8 taxa belonging to 4 genera (one new to science): Boxaster gen. nov., Noviaster Valette, 1929, Tylasteria Valette, 1929, Valettaster Lambert, 1914, and 4 families: Astropectinidae Gray, 1840, Goniasteridae Forbes, 1841, Sphaerasteridae Schöndorf, 1906 and Stauranderasteridae Spencer, 1913. Only a very few representatives of some of these taxa have formerly been reported from the Jurassic of Poland. Two species are new: Valettaster planus sp. nov. and Boxaster wapienensis gen. et sp. nov. The Jurassic starfish assemblage recognised from the Wapienno/Bielawy succession is interpreted as an offshore starfish fauna with the admixture of allochtonous shallow-water taxa. The lithology of the source deposits indicates their transport by storm agitation and/or mass movements. This fact strongly influenced the preservation state, all collected plates being disarticulated and most of them abraded.

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Badenian (Middle Miocene) echinoids and starfish from western Ukraine, and their biogeographic and stratigraphic significance

Radwański A., Górka M., Wysocka A.

Acta Geologica Polonica

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2014

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Vol. 64, no. 2

207--247

EN

Echinoderms from the Badenian (Middle Miocene) of the Fore-Carpathian Basin of western Ukraine are facies restricted. The Mykolaiv Beds, stratigraphically older, yielded the starfish Astropecten forbesi (complete skeletons), two genera of sand dollars (Parascutella, Parmulechinus), and numerous other echinoids of the genera Psammechinus , Echinocyamus, Spatangus, Hemipatagus, Echinocardium, Clypeaster, Echinolampas, and Conolampas. The stratigraphically younger, calcareous Ternopil Beds yielded Eucidaris (complete coronae, isolated spines), Arbacina , Brissus, and Rhabdobrissus. Sixteen species of echinoids are distinguished and/or commented. A new brissid, Rhabdobrissus tarnopolensis sp. nov., is established. A mass occurrence of some species (Psammechinus dubius and Hemipatagus ocellatus) contrasts with that of mass aggregations (sand dollars and Echinocardium leopolitanum) by dynamic events in selected layers of proximal tempestites. Of special note is the occurrence of very small specimens, interpreted as juveniles (‘babies’) having been swept out of their restricted biotopes (‘nurseries’). Some species hitherto regarded as of Early Miocene age, and the problem of their persistence beyond the Fore-Carpathian Basin and/or migration into that basin during the Middle Miocene transgression are discussed.

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A goniasterid starfish (Echinodermata, Asteroidea) preserved in a mid-Miocene rhyolitic ignimbrite, northwest Romania

Jagt J., Codrea V.

Acta Geologica Polonica

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2010

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Vol. 60, no. 2

275-282

EN

A well-preserved, near-complete goniasterid asteroid, provisionally referred to the genus Ceramaster, is recorded from a rhyolitic ignimbrite assigned to the Dej Tuff Formation, exposed near Ciceu Giurgesti (northwest Romania). The main interest of this specimen lies in the fact that it constitutes a rare example of preservation of (shallow-) marine biota, and echinoderms in particular, in volcanic strata. Superficially, overall disc shape and size, as well as ornament of marginal and abactinal ossicles, resemble to some extent that of coeval and slightly younger material from the Paratethys (south-central Poland, Austria) and the North Sea Basin (northwest Belgium), previously assigned to Ceramaster. So far, only the Polish and Austrian material has been formally named; however, this might actually represent but a single species. The record from Belgium refers to a form which is either conspecific with C. muelleri from the Paratethys, or represents a closely related taxon. These, and associated asteroids (e.g., Astropectinidae, Luidiidae), are in need of a modern taxonomic revision and a reappraisal of their palaeoecology is called for as well.

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Aberrantne rozgwiazdy z rodzaju Sphaeraster Quenstedt, 1875, w profilu oksfordu Wapienno/Bielawy na Kujawach

Radwańska U.

Volumina Jurassica

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2003

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Vol. 1, no. 1

63-70