#annularia
- Annularia — A fossil plant genus of the order Equisetales, characteristic of the Carboniferous and Permian periods, representing the star-shaped whorled foliage of the ancient trees known as Calamites. The linear or lanceolate leaves were structurally joined at the base into a distinct ring, forming a circular fossil imprint that provides crucial clues about the structure of Paleozoic swamp forests.