Pseudocorax Priem, 1897
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publication ID |
https://doi.org/ 10.4202/app.01117.2023 |
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persistent identifier |
https://treatment.plazi.org/id/03E18741-1303-EF08-DF68-F933FBF2FE67 |
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treatment provided by |
Felipe |
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scientific name |
Pseudocorax Priem, 1897 |
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Genus Pseudocorax Priem, 1897
Type species: Corax affinis Münster in Agassiz, 1843, Maastrichtian , Netherlands .
Pseudocorax affinis (Münster in Agassiz, 1843) Fig. 2H View Fig .
Material.—Six isolated teeth ( SOM: table 1): five (RU-EFP-02463, 2832, 4158, 4166, 4167) from the MFL and one (RU-
EFP-04168) collected as float. All from the MaastrichtianDanian Hornerstown Formation, Edelman Fossil Park, Mantua Township, New Jersey, USA.
Description.—All of the teeth are small, measuring less than 13 mm in mesiodistal length at the base of the crown. The crown is labiolingually thin and moderately inclined posteriorly with a flat labial face and weakly-convex lingual face. The base of the crown extends into distinct, obliquely-oriented mesial and distal heels, with the rounded distal heel being nearly detached from the central cusp whereas the mesial heel forms a comparatively-weaker convex berm. The mesial heel possesses a weakly-pointed apex in specimens RU-EFP-04167 and 4168. Fine serrations are present along the entire mesial and distal margins of the central cusp and both heels. The root is tall, generally of approximately the same height as the central cusp, with large mesial and distal lobes that are divided by a broadly-triangular basal notch. A shallow nutrient groove bisects a weak, yet distinct, lingual protuberance. Subtle, rounded ridges extend just beneath the crown-root boundary from this protuberance to the mesial and distal margins of the root. These margins each exhibit a concavity just below the crown-root boundary.
Remarks.—The specimens can be differentiated from Squalicorax Whitley, 1939 , by their gracile morphology and presence of a nutrient groove ( Hamm and Cicimurri 2011). The specimens can be assigned to the genus Pseudocorax based on their possession of a weakly-inclined and triangular central cusp that is flanked mesially and distally by oblique heels, and a large root with weakly-separated lobes that have slightly-concave mesial and distal edges ( Jambura et al. 2021). Among the six currently-recognized species of Pseudocorax , only Pseudocorax affinis possesses serrations ( Hamm and Shimada 2007). The presence of a nutrient groove on the lingual side of the root is characteristic of Pseudocorax affinis ( Case et al. 2017) .
The specimens described here represent the first recovery of Pseudocorax from the MFL. Case and Cappetta (2004) reported two teeth of Pseudocorax affinis from the lower Maastrichtian Navesink Formation at Big Brook in Marlboro, NJ. “ Pseudocorax affinis ” has also been reported from the Campanian of Georgia ( Case and Schwimmer 1988) and Alabama ( Applegate 1970), though due to their lack of serrations, those specimens should be assigned to Pseudocorax laevis Leriche, 1906 ( Shimada 2009). Teeth of the species Pseudocorax laevis (possibly including Pseudocorax granti Cappetta & Case, 1975 , Hamm and Shimada 2007) have also been described from the Campanian Marshalltown and Mount Laurel formations near the Chesapeake and Delaware Canal area in Delaware ( Lauginger and Hartstein 1983). Pseudocorax teeth have been reported from the Paleocene only once before: Eaton et al. (1989) described several specimens from the Shotgun Member of the Fort Union Formation of Wyoming, although they were interpreted as being reworked from Cretaceous deposits.
Stratigraphic and geographic range.—Upper Cretaceous (Maastrichtian) to lower Paleocene (Danian) of New Jersey in USA, Denmark, Netherlands, and Africa.
Squaliformes Goodrich, 1909
Genus Squalus Linnaeus, 1758
Type species: Squalus acanthias Linnaeus, 1758 , Recent, temperate waters, worldwide.
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Bulgarian Academy of Sciences |
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