Pteridophytes are the ancient group of vascular plants commonly known as ferns and their allies. It represent one of the most primitive lineages of land plants. These plants are non-flowering, have a vast diversity, ranging from tiny moss-like species to large tree ferns. Their evolutionary significance is considerable, as they represent the intermediate step between non-vascular plants like bryophytes and the more advanced seed-producing plants (gymnosperms and angiosperms). A fascinating aspect of pteridophytes is their highly specialized and varied epidermal structures, which play critical roles in protecting the plant from environmental stress and regulating physiological processes such as water conservation, gas exchange, and nutrient uptake. Among the various parts of the pteridophyte, the pinnae (leaflets) exhibit particularly complex epidermal features that contribute significantly to the plant’s overall functionality and adaptation to various ecological niches. Pinnae, or the leaflets of pteridophytes, exhibit a range of specialized anatomical features that are essential for the plant’s survival and efficient functioning. The structure of the pinnae, with their intricate arrangement of epidermal cells and associated structures, reveals much about how ferns adapt to their environment.