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Faunas, Floras and Biostratigraphy |
Palaeontological Institute of the Russian Academy of Sciences, 123 Profsoyuznaya Street, 117647, Moscow, Russia
New fish material, including microremains from the Tournaisian-Viséan interval of the Moscow Syneclise, Northern Urals and Voronezh Anteclise of the East European Platform, comprises new species of Chondrichthyes: Lissodus pectinatus sp. nov., (?)Diplodoselache antiqua sp. nov., Eunemacanthus krapivnensis sp. nov. Other fish taxa include Stethacanthus obtusus (Trautschold 1874), ‘Orodus’ tumidus (Trautschold 1874) and Taeniolepis trautscholdi (Chabakov 1927) are revised.
Tournaisian-Viséan deposits on the East European Platform are mostly represented by shallow marine or near-shore hyposaline facies with alternating salinity levels. Four major types of aquatic vertebrate environments are suggested: (1) continental fresh- and brackishwater; (2) lagoonal and estuarine with unstable salinity levels; (3) near-shore intertidal; and (4) off-shore neritic. Osteolepidids and actinopterygians are found in two or even three environmental zones, which suggests that they were eurybiontic and tolerant to changes of salinity, temperatures, hydrodynamics and other parameters of the basin. The most stenobiont forms are: Diplodoselache, Ageleodus, Pycnoctenion and dipnoans (1); Deltodus, Streblodus, Copodus and petalodontids (2); Lissodus and actinistians (4). The environmental distribution of the other groups is not as well expressed.
