Pachymylus
Pachymylus is an extinct genus of chimaera belonging to the family Callorhinchidae. The type species. P. leedsi was described by Arthur [Smith Woodward|A. S. Woodward] in 1892, and is known from the Middle-Late Jurassic Oxford Clay of Peterborough, England. The type material consisted of a large mandibular tooth and two palatine teeth. Indeterminate remains of the genus are also known from the Middle Jurassic of France.