Ptyctodus species come in a variety of different sizes, measured data shows three specimens being 94 millimeters, 24 millimeters, 22 millimeters in length, 23 millimeters, 6 millimeters, 4 millimeter in height, and 18 millimeters, 7 millimeters, and 4 millimeters in thickness. Through time, an evolutionary morphological trait is that the species within
Ptyctodontidae reduce the dermal armour. The dentition of the
Ptyctodus has dental elements that are very similarly observed in
chimaeroids. The are expressed as fine punctae in parallel rows. They were also armed with dorsal fin spines closely seen in
Hetercanthus and
Phlyctaenacanthus.
Ptyctodus lived in a
nektonic carnivore type-ecology and in carbonate, lagoonal, and shallow subtidal environments. Due to structure and shape of the teeth
Ptyctodus would easily be able to crush shellfish like organisms at the bottom of the ocean floors, feeding mainly off of that. They also must seem to have been very agile swimmers, able to escape predators, like
arthrodires. == Species ==