Resumen de Environmental significance of some Mesozoic "Porostromata" calcareous algae
Detley K. Richter, Bárbel Kube, H. Gielisch, Ovidiu Dragastan
The associations fo Cyanobacteria and Siphonophyta (Order Bryopsidales) calcareous algae from Carpathians and Hellenic carbonate platforms provide a general environmental model characteristic for inner and outer platform domains.
In the inner platform were identified the following associations by zones: supratidal - Apophoretella bancilai, Charophytes and Ostracodes; intertidal - Rivularia dianae, Perachoraella doinae; restricted lagoon - Rivularia theodori, Apophoretella dobunnorum; semi-restricted lagoon - Apophoretella brindusae, Paraortonella solitaria, Ortonella lemoineae, Rivularia carpathica (Cyanobacteria) and Hedstroemia clavata, Garwoodia fissa (Siphonophyta, Bryopsidales).
The definitory associations for the outer platform were subdivided in two zones: reef-barrier with Perachoraella aegaeica, Apophoretella mutiui, Hedstroemia solida and subtidal - with Pratumiella conradi and Hedstroemia solida. Rivularia corinthiana n. sp. from Pleistocene of Isthmus of Corinth (Greece) is described. The biotope of environmental zones and the sinking or uplifting of the platform have a direct influence on the thallus morphology, size and "stability" of the associations.
