Toxoprion

Toxoprion (Ancient Greek for "bow saw") is an extinct genus of eugeneodont holocephalids whose fossils are found in marine strata from the Early Carboniferous until the Late Permian.[1]

Toxoprion Temporal range: 358–259 Ma PreꞒ Ꞓ O S D C P T J K Pg N Early Carboniferous to Late Permian
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Chondrichthyes
Order:	†Eugeneodontida
Family:	†Helicoprionidae
Genus:	†Toxoprion Hay, 1909
Type species
Toxoprion lecontei Hay, 1909

Description

Toxoprion was one of the many Carboniferous eugeneodonts which bore 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, 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. As with other helicoprionids, Toxoprion instead added teeth to the terminal end of the jaw and grew 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 were arranged, and πριόνι (prióni), for the number of triangular serrated teeth it had. While originally suggested to be a member of the genus Helicoprion, it was later shown to be a distinct animal. The genus contains one species, T. lecontei.[3]

References

1. Hay, O.P. "†Toxoprion Hay 1909 (chimaera)". Fossilworks. Retrieved 18 September 2014.
2. Pollerspöck, Jürgen. "Toxoprion lecontei". Shark References.com. Retrieved 18 September 2014.
3. "Helicoprion". Geocities. Retrieved 18 September 2014.