Protocentrophorus

This squaloid shark had small teeth that combined traits from two modern shark families, Squalidae and Centrophoridae. The lower teeth were flattened from front to back, as seen in Centrophoridae, and wider than they were tall, like those in Squalidae. The base of the tooth root was flat, long, and almost vertical, similar to Centrophoridae, but it lacked the special hollow for overlapping teeth and the prominent root face typical of Squalidae. The apron, a part of the tooth, was moderately high and didn't extend past the base of the root, while the uvula, a small part of the tooth, was reduced and not prominent. Additionally, there was no infundibulum, a funnel-like structure, present.^[2]