Allodaposuchus, NOPCSA, 1928

Martin, Jeremy E., Delfino, Massimo, Garcia, Géraldine, Godefroit, Pascal, Berton, Stéphane & Valentin, Xavier, 2016, New specimens of Allodaposuchus precedens from France: intraspecific variability and the diversity of European Late Cretaceous eusuchians, Zoological Journal of the Linnean Society 176 (3), pp. 607-631 : 610-611

publication ID	https://doi.org/ 10.1111/zoj.12331
persistent identifier	https://treatment.plazi.org/id/860A821E-FFCB-C262-BC92-0D46FBFEDEEE
treatment provided by	Marcus
scientific name	Allodaposuchus
status

Treatment

GENUS ALLODAPOSUCHUS NOPCSA, 1928

ALLODAPOSUCHUS PRECEDENS NOPCSA, 1928 (SEE

FIGS 2–10 View Figure 2 View Figure 3 View Figure 4 View Figure 5 View Figure 6 View Figure 7 View Figure 8 View Figure 9 View Figure 10 )

Referred specimens: MMS /VBN-12-42, a nearly complete skull of a juvenile; MMS /VBN-12-10A, a complete adult skull; MMS /VBN-12-10B, a right dentary associated with the large adult skull MMS /VBN-12- 10A; MMS /VBN-93-28, a dorsoventrally compressed subadult skull; MMS /VBN-12-10D, a juvenile skull table; MMS /VBN-93-29, isolated fragmentary left maxilla; MMS /VBN-93-30, isolated fragmentary right maxilla possibly corresponding to MMS /VBN-93-29; MMS / VBN-12-10F, one dorsal osteoderm; MMS /VBN-02- 37, a left femur.

Occurrence: Late Campanian fluvial deposits of Velaux- La Bastide Neuve, Bouches du Rhône Department, southern France.

Emended diagnosis: Allodaposuchus precedens is a hylaeochampsid crocodilian characterized by the following combination of characters: mesorostrine skull; external naris large and rostrodorsally orientated; ectopterygoid bordering the posterior tooth row margin; laterally open canalis quadratosquamosoexoccipitalis; participation of the nasals in the posterior portion of the external naris; largest maxillary alveolus in fourth position; 13 maxillary alveoli. Allodaposuchus precedens differs from Acynodon , Hylaeochampsa and Iharkutosuchus by having a mesorostrine skull, and from Acynodon and Iharkutosuchus by having an enlarged fourth maxillary alveolus and conical pointed teeth. Allodaposuchus precedens differs from A. iberoccitanus by lacking a preorbital ridge, and from I. makadii by lacking multicusped posterior maxillary teeth and by having open supratemporal fenestrae.

DESCRIPTION

Preservation, form and general features: The skull MMS/ VBN-12-42 ( Fig. 2 View Figure 2 ) is nearly complete, but the anterior region is slightly compressed in the posterior direction and the right lateral suface of the premaxilla and the maxilla is absent up to the fourth maxillary alveolus. The right quadrate is mostly missing and the left quadrate condyle has been eroded. The pterygoids are only partly preserved (the internal choana is absent). The posteroventral tip of the ectopterygoid is broken off. In dorsal view, the rostrum is relatively elongat- ed (Supporting Information Appendix S1), with just a hint of a premaxillary–maxillary notch on the left side (the right side is damaged). In lateral view, the ventral edge of the skull is markedly undulated, with the apex of the convexities corresponding to the middle of the premaxilla, the fourth and the tenth maxillary alveoli, and the bottom of the concavities corresponding to the premaxilla–maxilla suture and the sixth interalveolar space. The skull MMS/VBN-12-10A ( Figs 3 View Figure 3 , 4 View Figure 4 ) is complete and experienced little deformation, only detectable by a slight dorsoventral compression of the occipital condyle ( Fig. 5 View Figure 5 ). One main fracture is transversally orientated through the skull at the level of the interorbital area and reaches the fourth maxillary alveolus on the left side. On the ventral surface, this fracture extends from the anterior edge of the fourth maxillary left alveolus to the anterior edge of the eleventh right maxillary alveolus. The right premaxilla is bent inward as shown by the orientation of the teeth. The left tooth row is deformed and deflected to the outer side of the skull, as indicated by the shift of the row away from the foramina located medially ( Fig. 4 View Figure 4 ). The third skull, MMS/VBN-93-28 ( Fig. 6 View Figure 6 ), is less complete and is missing much of the palate, the temporal regions and several zones of the skull table. It is comparable in size to MMS/ VBN-12-42, but experienced some dorsoventral compression, resulting in a broader outline of the rostrum. The fourth skull, MMS/VBN-12-10D ( Fig. 7 View Figure 7 ), consists of a skull table and quadrate branch, preserving details of the otic area and of the supratemporal fenestrae. In the large specimen MMS/VBN-12-10A the skull table is concave not only because the rims of the supratemporal fenestra are slightly raised, but because the areas anterior and posterior to the fenestrae are distinctly depressed. The interfenestral space is less than half the interorbital space. The posterior surface of the rostrum of MMS/VBN-12-42 is affected by three circular holes of different sizes, the largest being more than 1 cm in diameter. The origin of these holes is uncertain, but could be post-mortem as there is no sign of reaction tissue formed during healing.

Ornamentation: MMS/VBN-12-10A has deep irregular pits in the skull table and interorbital dorsal surface. These pits are numerous, but shallow on the rostrum and they become circular and more spaced above the maxillary tooth row. The pits become deeper and vermiform along the infratemporal bar. The quadratojugal is dorsally inflated with pits that do not spread over its medial area. Anterior to the orbits, the thick orbital bulge has a very small pitted surface. The lateral side of the squamosal is pierced with large foramina. Pits on the postorbital are similar to the anterior orbital rim. On the dorsal surface of the squamosal, there is a large depression, as in Rugosuchus nonganensis ( Wu, Brinkman & Fox, 2001) .