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

Abstract

Ordovician conodont specimens resembling Oistodus 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 from Drepanoistodus forceps (LINDSTROM, 1955) in the Early Ordovician. (Less)