Description
Original description after Agassiz (1856) p. 272-273 [#26}, [2942]: Scymnus occidentalis, Agassiz, Pl. I, figs. 9—13.
The few species upon which Cuvier founded the genus Scymnus have been of late subdivided by Müller and Henle into two genera — Scymnus proper, and Laemargus — all of which are only known among the living. It is another of the highly interesting discoveries of Mr. Blake to have brought home two teeth from the Tertiaries of California belonging to this remarkable type. I would even not hesitate to consider them as indicating a distinct genus, were the number of specimens sufficient to warrant the inference that the teeth present in every position of mouth as great a difference from the true Scymnus and Laemargus as the two latter present when compared with one another. At all events, these teeth belong to the genus Scymnus, as established by Cuvier, and constitute a very distinct species, on account of the strong bend backwards of the main point of the tooth, and the distinct, and rather marked serration of the edges of the crown. Moreover, the inclination of the central point upon its basis gives these teeth a certain resemblance to those of Spinax and Centrophorus, and still more with Galeocerdo . The connexion of the teeth of the same row of the jaw with one another, was evidently the same as in the Scymnus and Laemargus , as is plainly shown, by the notch upon the inner surface of the root, and the articulating tubercle at the base of the enamel in both sides. The discovery of a fossil Scymnus in the Tertiaries of California is particularly interesting in a geographical point of view, since thus far no representative of the type has been found in the Pacific Ocean.

Remarks
shark-references Species-ID=6810;

References