Acrotemnus

The following species are known: • A. faba Agassiz, 1836 - Turonian of England (English Chalk) • A. megafrendodon (Shimada, Williamson & Sealey, 2010) - Turonian of New Mexico, USA (Mancos Shale) (=Macropycnodon megafrendodon Shimada, 2010) Acrotemnus was initially known from just the type species A. faba described by Louis Agassiz in 1843 from specimens collected in England. In 1939, Hibbard described a large-sized pycnodont from a tooth plate from Kansas, which he placed in Coelodus as C. streckeri. In 2010, Shimada, Williamson & Sealey described a gigantic pycnodont known from a few tooth plates found in New Mexico as Macropycnodon megafrendodon, placing C. streckeri in the same genus. == Description ==

A. megafrendodon is known from isolated teeth, the largest being in width. A comparison between the tooth-to-body size ratio of more completely known relatives, such as Coelodus saturnus, suggests that A. megafrendodon could have reached comparatively gigantic body sizes of over . This would make it among the largest pycnodonts, especially given that the majority do not reach over in length. The partial specimen of A. cf. streckeri described in 2021 is estimated to have been roughly in length, supporting these estimates. ==See also==