Middle Devonian parathuramminid and earlandiid foraminifers from shallow marine carbonates of the Carnic Alps (Austria)

Abstract

AbstractThe Devonian of the Carnic Alps (Austria) is developed in different facies. The shallow marine facies is up to 1200 m thick. The Feldkogel Limestone of the Polinik Formation, >330 m thick, was dated as Eifelian–Late Devonian. The Feldkogel Limestone at Mount Polinik is developed in a peritidal facies composed of subtidal, intertidal, and supratidal deposits. Subtidal sediments are represented by dark grayAmphiporalimestone and intertidal deposits by laminated and partly bioturbated grainstone and packstone, ostracode wackestone to packstone, and locally intercalated intraclast breccias documenting tidal channel fills. Laminated microbial mats (stromatolites) formed in a supratidal depositional environment. Grainstone and packstone contain abundant unilocular parathuramminid foraminifers. This latter group encompasses a diversified assemblage of ivanovellids, parathuramminids, uralinellids, and irregularinoids; some earlandiids are also present. They are dated herein as late Eifelian–early Givetian. These foraminifers provide a more precise systematics of these taxa, which often have not been studied for more than half a century. The taxonomic problems of their assignment to foraminifers, pseudo-foraminifers, calcitarcha, thaumatoporellaceans, volvocaleans, or other algae are also discussed. Several taxa are emendated: Parathuramminida, Parathuramminoidea, Irregularinoidea, Eovolutinidae, Ivanovellidae, Parathuramminidae, Uralinellidae,Ivanovella,Elenella,Neoarchaesphaera,Parathurammina,Bykovaella,Uralinella, andParacaligella. The new taxa are:Ivanovella reitlingeraen. sp.,Elenella polinikensisn. sp.,Uralinella sabirovin. sp., andRadiosphaerella poyarkovin. sp.