Palaeocarcharodon is arguably the most sought after Paleogene shark tooth in eastern North America. The striking similarity of these teeth, with those of the extant Great White undoubtedly feeds this collecting priority. Compared with Otodus (and most other sharks), this species' distribution is very limited in both time and space. This genus also serves as a flash-point in the Great White evolution debate. One viewpoint, as argued by Bob Purdy (1996), traces the lineage Palaeocarcharodon - Carcharodon auriculatus - Carcharodon megalodon - Carcharodon carcharias. The alternate scenario contends that Otodus evolved from Cretalamna, and terminated with Carcharocles megalodon (the modern Great White having nothing to do with either Palaeocarcharodon or C. megalodon). (See: Seque: Otodus-Carcharocles Slide Show.) In addition to rarity and importance, these teeth have another important feature — they are aesthetically very pleasing.

Even if the stratigraphic position is unknown, it would be difficult not to recognize Palaeocarcharodon teeth. Labio-lingually compressed triangular teeth with coarse & irregular serrations and usually combined with serrate lateral cusplets is not a common tooth-design. In the western Atlantic, these are medium-sized teeth, usually less than 3 cm. Moroccan specimens exceed 5 cm with reports of them reaching the 6 cm range. The dentition is of a cutting-design (See: Palaeocarcharodon Slide Show) and has a delicate quality when compared with those of Otodus.

Palaeocarcharodon orientalis (SINZOW, 1899) is currently thought to be the only valid member of this genus. Cappetta (1987) ascribed them to the Palaeocene of North & Western Africa and the Soviet Union. Case (1989) reported them from the Palaeocene of Maryland (USA) and Purdy (1998) from the Williamsburg Formation (Thanetian - Late Palaeocene) of South Carolina.. Their abrupt appearance and disappearance remains a mystery.

Fig. 2 - Palaeocarcharodon orientalis - Lower A2 Piscataway Mbr, Aquia Frm (Late Palaeocene) Landover, Maryland From the collection of Bill Heim

Fig. 3 - P. orientalis - Lower posteriolateral Aquia Frm (Late Palaeocene) Redskins Stadium, Landover, Maryland From the collection of Bill Heim

Fig. 4 - Palaeocarcharodon orientalis - Upper Anterior Piscataway Mbr, Aquia Frm ('Zone' 2, Late Palaeocene) Charles Co., Maryland From the collection of Gary Grimsley

Fig. 5 - Palaeocarcharodon orientalis Lower A2 Piscataway Mbr, Aquia Frm ('Zone' 2, Late Palaeocene) Charles Co., Maryland From the collection of Gary Grimsley

Fig. 6 - Palaeocarcharodon orientalis Upper Posterior Piscataway Mbr, Aquia Frm ('Zone' 2, Late Palaeocene) Charles Co., Maryland

Supplemental References

Case, G., 1989. Palaeocarcharodon orientalis (Sinzow) (Neoselachii: cretoxirhinidae), from the Paleocene of Maryland, USA. Paleovertebrata, 19(1): 1-6.