Pholidophoriforms

Pholidophoriforms are an extinct group of fish that lived during the Devonian period, approximately 416 to 357 million years ago. They were characterized by their small size, with most species ranging from a few centimeters to about 20 centimeters in length.

Pholidophoriforms were divided into several families, including the Acanthodiformes, Acanthodii, and Gyracanthiformes. Many species within these families bore bony plates on their bodies, such as the Acanthodiformes, which featured armor plating on their bodies, likely aiding in protection against predators.

Pholidophoriforms were largely aquatic and were found in both freshwater and marine environments. Their fossils have been discovered in sedimentary rock formations from various parts of the world, including Europe, North America, and Australia.

Research has suggested that Pholidophoriforms likely belonged to the clade of jawed vertebrates and are more closely related to modern sharks and rays than to their once-thought relatives among the lobe-finned fish. However, the exact classification and relationships between pholidophoriforms and other groups of ancient fishes remain subject to ongoing research and debate.

Many of the pholidophoriform species are recognized and named based on fossil evidence, with over 100 species described in scientific literature. Their discovery and study contribute significantly to the understanding of the evolution of early vertebrates and the diversity of life on Earth during the Devonian period.