Pterichthyodes
Pterichthyodes is a genus of antiarch placoderm fishes from the Devonian period. Its fossils have been discovered in Scotland.[1] They were one of the first species recognized for what they were, as their fossils are common in the Old Red Sandstone formation studied by geologists in the early 19th century. Due to their extreme divergence from modern-day fish, they were a puzzle unsolved until Charles Darwin brought forward his theories on evolution.[citation needed]
As with all other antiarchs, Pterichthyodes had heavily armored heads and forebodies, while their scaly tails were unarmored. Specimen length ranges from 8 inches (20 cm) to...read more