Toxoprion

Toxoprion (Ancient Greek for "bow saw") is an extinct Genus of eugeneodont (true origin teeth) Holocephalids of the Permian.^[1]There is only one member of the Genus, T. lecontei, which is known as an Edestid, one of the many Carboniferous eugeneodonts which beared a palatoquadrate fused to its skull or reduced in other forms, and had its heavily serrated teeth grow outwards on the symphysis of the lower jaw similar to a rounded saw.^[2] Despite its jaw showing similarities to another eugeneodont Genus, Helicoprion, the teeth of Toxoprion do not grow into a "whorl", in which smaller and earlier teeth are overlapped with larger teeth grown later in life, to where the jaw resembles the shell of an ammonite. The Toxoprion jaw instead adds teeth to the terminal end of the jaw and grows in a downward arch, not revolving around preceding teeth.

Taxonomy

The genus acquired its name from the greek word "τόξο" (tóxo), from the bow shaped jaw on which the teeth of the creature was arranged upon, and "πριόνι" (prióni), for the amount of triangular serrated teeth it had. While originally suggested to be a member of the Helicoprion genus, it was shown to be biologically different creature and then placed in its own Genus instead.^[3]

References