Icriodus marieae, a new icriodontid conodont species from the Middle Devonian
نویسندگان
چکیده
A new conodont species, Icriodus marieae, is described from pelagic limestone beds of the Carnic Alps (Austria). Specimens are obtained from the upper part of the Valentin Formation (Central Carnic Alps) and range from the latest Eifelian to middle Givetian. Significantly differing from other icriodontid conodonts is that the icriodontan element of the new species develops only three denticles on either lateral denticle row, which are constricted to the central part of the element. The anterior part of the element is free of lateral row denticles and consists of two to four denticles, which have a fan-shaped outline in lateral view. The anterior part as well as the posterior part (consisting of cusp and two to three pre-cusp denticles) is higher than the denticles of the central part of the element. Shape analysis confirms that the parameters chosen for landmarks (element size relation and denticle setting) show little variation between different specimens.
منابع مشابه
Middle Devonian-Early Carboniferous Conodont Faunas from the Khoshyeilagh Formation, Alborz Mountains, North Iran
Conodonts of Khoshyeilagh Formation, the most complete section of Devonian rocks in the Alborz Mountains, northern Iran, has been studied, and subspecies of the genera Icriodus, Bipennatus, Polygnathus, Pelekysgnathus, Ancyrodella, Palmatolepis, Bispathodus, Scaphignathus, Clydagnathus, Gnathodus, Scaliognathus and Dollymae have been obtained from the studied section. The faunas indicate an Eif...
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