1,721,378 research outputs found
New data on Pankowskichthys libanicus (Pycnodontiformes, Gladiopycnodontidae), a fossil fish from the marine Upper Cretaceous of Lebanon
No full textA male specimen of Pankowskichthys libanicus is described and compared with the holotype of the species, considered as a female. The comparison with Ducrotayichthys cornutus is also done
New data on the osteology and relationships of Flagellipinna rhomboides, a pycnodont fish (Pycnodontidae) from the Cenomanian (Upper Cretaceous) of Lebanon
No full textThe skeleton of the fossil fish Flagellipinna rhomboides, a Pycnodontidae from the marine Cenomanian (Late Cretaceous) of Lebanon, is described and its systematic position within the family discussed. The frontal is short, curved and broad. The brush-like process of the parietal is shortened. The neural and haemal arches are in hyper-complex contact. The last neural spines before the tail are vestigial. The anal fin contains 50 to 53 pterygiophores. The caudal fin is vertical. Three hypochordals are hypertrophied. There are bar-scales not only in the abdominal but also in the caudal region of the body. All these evolved characters clearly indicate that F. rhomboides belongs to the Nursalliini, a specialized tribe of the subfamily Pycnodontinae
A new insight into the Protobramidae (Teleostei, Tselfatiiformes), a fossil fish family from the marine Cenomanian (Upper Cretaceous) of Lebanon
No full textThe study of new specimens of Abisaadichthys and Eusebichthys, two genera belonging to the Protobramidae (Tselfatiiformes), a teleost family from the marine Cenomanian (Upper Cretaceous) of Lebanon, gives a better knowledge of the skeleton of these fishes. The discovery of a pelvic girdle in thoracic position in Eusebichthys allows a better understanding of the phylogeny within the family
Comments on the phylogenetic relationships of Pholidorhynchodon malzannii and Eurycormus speciosus (Teleostei, "Pholidophoriformes"), two Mesozoic tropical fishes
No full textThe phylogenetic relationships of Pholidorhynchodon malzannii and Eurycormus speciosus, two Mesozoic teleosts of the "Pholidophoriformes" lineage, are commented on the basis of the available osteological data. To conclude, the belonging of Pholidorhynchodon to the Pholidophoridae sensu stricto is contested and the genus is ranged within the family Ankylophoridae. It is also shown that Eurycormus is more evolved than Catervariolus and not less evolved, as thought by some. Anatomical arguments are developed that militate for the inclusion of Eurycormus in the family Ankylophoridae
Osteology and relationships of Lebrunichthys nammourensis gen. And sp. nov. (Teleostei, Crossognathiformes, Pachyrhizodontidae), a fossil fish from the marine Upper Cretaceous of Lebanon
No full textThe osteology and the relationships of Lebrunichthys nammourensis gen. and sp. nov., a new pachyrhizodontid fish from the marine Upper Cenomanian of Lebanon, are studied in details. The new genus belongs to the subgroup of Pachyrhizodontidae having a posterior pointed process on the pterotic. The characters of the caudal skeleton indicate that Lebrunichthys occupies an intermediate systematic position between Stanhopeichthys, one the one hand, and all the other genera of the subgroup, on the other hand
A batoid hembryo (Chondrichthyes: Batoidea), from the marine upper Cenomanian (Late Cretaceous) Sannine limestone of Hjoula, Lebanon
No full textHere, a fossil egg case that contains a well-preserved embryo is described. The embryo is characterised by (i) a rostral cartilage, (ii) some ribs, (iii) and a well-developed stinger; (iv) absence of thoracolumbar synarcual. This represents an unique combination of characters which demonstrate that the batoid that produced the egg case was a completely new form, possibly a stem–Myliobatiformes, which remains undetermined in the absence–to date–of any comparable adult specimen. SEM morphological analysis demonstrates that the wall of the fossil egg case was multilaminate, made up of collagen fibres (with a thickness of 2–4 μm): an ultrastructure that has been positively compared to the egg case of living Rajiformes (Raja asteria) and Myliobatifirmes (Hemitrygodon akajeri). The egg case also contains a mass that is interpreted as the remains of yolk sac, internally organised in platelets with a diameter of 25–35 μm. Since in living Myliobatiformes the egg cases disappears from inside the uterus before the end of the embryogenesis, the described fossil is interpreted as an embryo that was prematurely emitted by the pregnant mother, such as an abortion of a batoid dated to the Late Cretaceous
Osteology and relationships of Stanhopeichthys libanicus gen. And sp. nov. (Teleostei, Crossognathiformes, Pachyrhizodontidae) from the marine Cenomanian (Upper Cretaceous) of Lebanon
No full textThe osteology and the relationships of Stanhopeichthys libanicus gen. and sp. nov., a new pachyrhizodontid fish from the marine Upper Cenomanian of Hgula (Lebanon), are studied in details. The new genus belongs to the subgroup of Pachyrhizodontidae having a posterior pointed process on the pterotic. With the three last caudal vertebrae not fused, seven autogenous hupurals, three epurals and three uroneurals, Stanhopeichthys exhibits the less evolved caudal skeleton within that subgroup. Stanhopeichthys and the Italian genus Nardopiscis share a specialized character not present in other pachyrhizodontid fishes. Their two parietals are separated from each other by the posterior narrow region of the frontals and not by the supraoccipital
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