A fin spine of Recurvacanthus (Myriacanthidae, Holocephali) from the Posidonienschiefer (Early Jurassic) of SW Germany

Abstract

The fin spine of a myriacanthid holocephalian from the Lower Toarcian (Early Jurassic) Posidonienschiefer Formation of Ohmden, near Holzmaden, is described and, following comparison with other Mesozoic holocephalian dorsal fin spines, identified as Recurvacanthus uniserialis Duffin, 1981. This is the first record of Recurvacanthus from the German Posidonienschiefer, and only the second specimen known. In addition to extending both the stratigraphical and geographical ranges of the genus, the specimen represents an addition to the known chondrichthyan diversity of the Posidonienschiefer.