On the “Coccodus” lindstroemi species complex (Pycnodontiformes, Gladiopycnodontidae) from the marine Late Cretaceous of Lebanon, with the description of two new genera

Abstract

The osteology of “Coccodus” lindstroemi is studied in detail and it is demonstrated that this species does not belong to the genus Coccodus, but is a rather primitive member of the pycnodontiform family Gladiopycnodontidae. Indeed, the snout of “Coccodus” lindstroemi is elongated in a rostrum formed by the prefrontal and the premaxilla. This rostrum extends beyond the lower jaw level. The toothless premaxilla is sutured by its upper margin to the lower margin of the long and broad prefrontal. The pectoral fin is lost and replaced by a pectoral spine which articulates on the cleithrum. A long nuchal spine resting on the dermosupraoccipital is present. The body is entirely covered by scales that are flake-like in the abdominal region and scute-like in the caudal region. Joinvillichthys gen. nov. is thus erected with “Coccodus” lindstroemi as the type species. It is also shown that specimens with dumpier head and body, usually ranged in “Coccodus” lindstroemi, represent another species of the same genus for which the taxon Joinvillichthys kriweti gen. et sp. nov. is created. Specimens sometimes considered as possible juveniles of “Coccodus” lindstroemi form a distinctive new genus and species of gladiopycnodontid fish, Pankowskichthys libanicus gen. et sp. nov. Pankowskichthys differs from Joinvillichthys by many osteological structures.

Keywords

• Pycnodontiformes
• osteology
• relationships
• marine Cenomanian
• Lebanon