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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 flakelike 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.
The skeleton and the relationships of Libanopycnodus wenzi gen. et sp. nov. and of Sigmapycnodus giganteus gen. et sp. nov., two pycnodontiform fishes from the marine Cenomanian (Late Cretaceous) of Lebanon, are studied in detail. Both species belong to the family Pycnodontidae, as shown by their parietal brush-like process. Some osteological characters (bifid cloacal scale, large well visible dilatator fossa surrounded by the dermosphenotic and the dermopterotic, etc.) indicate that they are members of the subfamily Pycnodontinae. Libanopycnodus gen. nov. has the preopercle much deeper than the exposed region of the hyomandibula-dermohyomandibula and is the most primitive genus of this lineage. Sigmapycnodus gen. nov. is one of the most advanced members of the subfamily. It shares with Oropycnodus Poyato-Ariza & Wenz, 2002 and Pycnodus Agassiz, 1833 an apomorphy not present in the less specialized Pycnodontinae, the arcocentra in hypercomplex contact.
The osteology of Rhinopycnodus gabriellae gen. and sp. nov., a pycnodontiform fish from the marine Cenomanian (Late Cretaceous) of Lebanon, is studied in detail. This new fossil genus belongs to the family Pycnodontidae, as shown by the presence of a posterior brush-like process on its parietal. Its long and broad premaxilla, bearing one short and very broad tooth is the principal autapomorphy of this fish. Within the phylogeny of Pycnodontidae, Rhinopycnodus occupies an intermediate position between Ocloedus and Tepexichthys.
The osteology of Gladiopycnodus karami gen. et sp. nov., of Monocerichthys scheuchzeri gen. et sp. nov. and of Rostropycnodus gayeti gen. et sp. nov., three new fossil fishes from the marine Cenomanian (Late Cretaceous) of Lebanon, is studied in detail. Some of their cranial characters and the presence of a postcoelomic bone clearly refer these fishes to the order Pycnodontiformes. However, they differ from all other described Pycnodontiformes by two important characters. Their snout is elongated as a rostrum, formed by the enlarged prefrontal and the toothless premaxilla, with this premaxilla sutured by its upper margin to the lower margin of the prefrontal. Their pectoral fin is replaced by a strong spine articulated with the cleithrum. These two apomorphies justify the erection of a new family, the Gladiopycnodontidae. The skull of Monocerichthys scheuchzeri sp. nov. does not differ greatly from a classical pycnodontiform skull and this species seems to be the more primitive member of this new family. Gladiopycnodus karami gen. et sp. nov. and Rostropycnodus gayeti gen. et sp. nov. are much more specialized. They share some apomorphies not present in Monocerichthys scheuchzeri gen. et sp. nov., i. e., an extremely long rostrum and an elongated first anal pterygiophore that sustains with the postcoelomic bone a strong and long anal spine. Gladiopycnodontidae fam. nov. and Coccodontidae share a series of apomorphies that justify the erection of a new superfamily, Coccodontoidea, grouping these two families.
The osteology of Acrorhinichthys poyatoi gen. et sp. nov., a pycnodontid fish from the marine Cenomanian (Late Cretaceous) of Lebanon, is studied in detail. The new fossil genus belongs to the order Pycnodontiformes, but is less evolved than the Pycnodontidae. It still exhibits a few bony plates (= tesserae) in the gular region, 3 teeth on the premaxilla and 5 teeth on the dentary, and its parietal is devoid of a brush-like process. It shares a few characters with Akromystax, the most primitive taxon within Pycnodontidae, characters lost in the other members of the family.
