Sphenophytes

Sphenophytes, also known as horsetails, are a group of vascular plants belonging to the division Equisetophyta. They are ancient plants, with a fossil record dating back to the Devonian period, and are now represented by a single living genus, Equisetum. Sphenophytes are characterized by their jointed, hollow stems and whorls of leaves that are reduced to scales. Reproduction occurs via spores produced in cone-like structures called strobili, typically found at the tips of fertile stems. These plants are often found in moist habitats, such as riverbanks, marshes, and forests. The stems of some species are rich in silica, giving them a rough texture and leading to their historical use as a scouring agent. Sphenophytes are distinguished from other vascular plants by their unique stem anatomy and reproductive structures. Despite their ancient lineage, they remain a small but distinctive component of plant ecosystems worldwide. Their life cycle involves alternation of generations, with a dominant sporophyte stage and a small, independent gametophyte stage.