Filicopsida

Filicopsida is a taxonomic class within the division Pteridophyta, commonly known as ferns. This group encompasses a vast diversity of plants, characterized by their vascular tissues (xylem and phloem) and the absence of seeds and flowers. Ferns reproduce via spores, which are typically produced in structures called sporangia, often found on the underside of their leaves, or fronds.

The life cycle of a fern is an alternation of generations, involving a diploid sporophyte stage and a haploid gametophyte stage. The sporophyte is the familiar leafy fern plant, which produces spores. These spores germinate into small, often heart-shaped gametophytes, which then produce gametes. Fertilization of the egg by the sperm leads to the development of a new sporophyte.

Filicopsida are found in a wide range of habitats across the globe, though they are most abundant in moist, shaded environments. Their fronds exhibit a remarkable variety of shapes and sizes, from delicate, feathery structures to large, undivided blades. Some ferns are epiphytic, growing on other plants, while others are terrestrial, growing in soil. Fossil evidence suggests that ferns were a dominant plant group during the Carboniferous period.