Calamites
Calamites are extinct, tree-like plants that belonged to the class Equisetopsida. They lived during the Carboniferous and Permian periods and are known for their segmented, jointed stems that were covered in leaf scars. Calamites were closely related to modern-day horsetails and could grow to impressive heights, with some species reaching up to 30 meters tall. These plants played an important role in ancient ecosystems and are often found preserved as fossils in coal deposits.