gossopterids

Gossopterids are an extinct group of seed ferns that flourished during the Carboniferous and Permian periods, approximately 320 to 250 million years ago. They were among the dominant plant forms of their time, particularly in coal-forming swamp forests, where they contributed significantly to the vast peat deposits that later transformed into coal. The name "gossopteris" derives from the genus *Gossampinus*, though the term is often applied broadly to related ferns with similar leaf structures.

Gossopterids possessed large, compound leaves with pinnate or bipinnate venation, resembling those of modern ferns but belonging to a distinct lineage. Their fronds were typically attached to a woody stem, and some species developed large, woody trunks, suggesting a tree-like growth habit. Fossil evidence indicates they thrived in warm, humid climates, often alongside other seed plants like *Lepidodendron* and *Sigillaria*. Reproduction in gossopterids involved seeds rather than spores, distinguishing them from true ferns.

The group exhibits a wide range of morphological diversity, with over 100 described species across various genera, including *Gossampinus*, *Pecopteris*, and *Neuropteris*. Their leaves are among the most common fossils found in Carboniferous and Permian coal measures, providing valuable insights into paleoenvironments and paleoclimates. While their exact evolutionary relationships remain debated, molecular clock studies and fossil evidence suggest they were closely related to modern cycads and conifers, representing an important transitional group in the evolution of seed plants.

Gossopterids declined sharply during the Permian-Triassic extinction event, around 252 million years ago, likely due to climate shifts and environmental upheavals. Their extinction marked the end of the dominant coal forest ecosystems that had shaped the Carboniferous landscape, paving the way for the rise of gymnosperms in the Mesozoic era. Today, their fossils serve as key indicators of ancient ecosystems and remain subjects of ongoing paleontological research.