Anatolepis - a problematic Ordovician vertebrate reinterpreted as an arthropod

Abstract

The name Anatolepis heintzi was proposed by Bockelie & Fortey (1976) for a series of scale-bearing fragments from the Early Ordovician Valhallfonna Formation, northern Ny Friesland, Spitsbergen. The fragments were interpreted as the remains of heterostracan fishes - the oldest known vertebrates. A few months previously, similar fragments had been figured, but not named, by Nitecki, Gutschick & Repetski (1975) from the Early Ordovician El Paso Group of western Texas. These authors were uncertain as to the affinities of the material at hand but noted an apparent similarity in ornamentation to merostome arthropods described by Raasch (1939) and other authors.