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AnOistodus venustus-like conodont species from the Middle Ordovician of Baltoscandia

  • Anita Löfgren
Article

Abstract

Ordovician conodont specimens resemblingOistodus venustus Stauffer, 1935 have been reported from many areas. There is increasing evidence, however, that several lineages with homeomorphic conodont elements have erroneously been referred to one and the same species. I have investigated Baltoscandian conodont elements of this kind in order to find out about their origins and phylogenetic relationships with morphologically comparable elements from other areas. A natural grouping of finds from the Middle and lower Upper Ordovician of Baltoscandia is here described as belonging to a new species of a new genus,Venoistodus balticus n. gen., n. sp. The new species probably evolved paedomorphically fromDrepanoistodus forceps (Lindström, 1955) in the Early Ordovician.

Keywords

Conodonts Ordovician Baltoscandia Sweden Venoistodus balticus n. gen. n. sp. 

Kurzfassung

Ordovizische Conodonten, die denen vonOistodus venustus Stauffer, 1935 ähneln, sind von vielen Lokalitäten gemeldet worden. Indessen mehren sich die Hinweise, dass man früher verschiedene Entwicklungslinien homöomorpher Conodonten-Elemente ein und derselben Art zugeordnet hat. Derartige baltoskandische Conodonten-Elemente wurden untersucht, um ihre Herkunft und phylogenetische Verwandtschaft mit morphologisch vergleichbaren Elementen anderer Gebiete zu klären. Eine natürliche Gruppe von Funden aus dem Mittel- und unteren Ober-Ordovizium von Baltoskandia wird hier als neue Art einer neuen Gattung beschrieben:Venoistodus balticus n. gen., n. sp. Die neue Art hat sich möglicherweise paedomorphisch ausDrepanoistodus forceps (Lindström, 1955) im frühen Ordovizium entwickelt.

Schlüsselwörter

Conodonten Ordovizium Baltoskandia Schweden Venoistodus balticus n. gen. n. sp. 

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Copyright information

© E. Schweizerbart’sche Verlagsbuchhandlung 2003

Authors and Affiliations

  1. 1.Department of GeologyLund UniversityLundSweden

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