Silicified otoliths from the Maastrichtian type area (Netherlands, Belgium) document early gadiform and perciform fishes during the Late Cretaceous, prior to the K/Pg boundary extinction event

Abstract

The Maastrichtian is an important time interval in the evolution of modern bony fishes. Certain teleost groups that disappeared later during the catastrophic K/Pg boundary extinction event, flourished during this period, while the root stock of other groups that subsequently filled the void and evolved, were already represented. Otoliths constitute an important data set for the reconstruction of extinct teleost faunas and are often found to complement information gained from skeletal remains. Here we describe otoliths obtained from the type area of the Maastrichtian Stage, from various levels within the Maastricht Formation. This assemblage is unique in being preserved as silicified neomorphs and reflects a shallow-marine carbonate environment which is rarely preserved for otolith associations. A total of 49 specimens were recovered from the upper Maastrichtian of the Maastricht Formation, of which 39 could be identified and belong to 15 species, plus one from the overlying Danian. New insight is gained into early gadiform and perciform (sensu lato) diversification. Three new taxa are described: Archaemacruroides vanknippenbergi n. sp. (Gadiformes incertae sedis), Rhinocephalus cretaceus n. sp. (Gadiformes, Merlucciidae) and Cretaserranus maastrichtensis n. gen. et sp. (Perciformes, Serranidae?).