Revision of Dapedium LEACH, 1822 (Actinopterygii, Neopterygii, Halecostomi) from the Lower Jurassic Posidonia Shale of South Germany

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The actinopterygian (neopterygian) genus Dapedium LEACH is present in the Upper Liassic (Lower Jurassic, Lower Toarcian) Posidonia Shale of Southern Germany with three known species: D. caelatum QUENSTEDT, D. punctatum AGASSIZ and D. pholidotum (AGAS-SIZ). D. caelatum was redescribed recently and a neotype was proposed for the species. However, the taxonomic definition of the remaining two species is still insufficient. D. pholido-tum lacks a holotype, and the South German D. punctatum obviously differs from the holo-type of D. punctatum from the Lower Lias of England. Present work focusses on the South German specimens of the so called “D. punctatum” which obviously belong to a new, still undescribed species. For the description of the new species the South German specimens have to be compared to the holotype of D. punctatum which was studied so far only by AGASSIZ (1835, 1836) nearly 175 years ago and is housed today in the Oxford University Museum of Natural History (England). In order to identify diagnostic characters separating the new species from the Lower Liassic D. punctatum the skeletal anatomy and morphology of the holotype of D. punctatum is to be studied and analysed.