Genomosperma kidstonii

Genomosperma kidstonii was an ancient plant that existed during the Mississippian subdivision of the Carboniferous Period. It is significant because its ovules, which are fossilized seed-like structures, provide evidence for the early evolution of integuments, a key component of seeds.12

The ovules of Genomosperma kidstonii featured an elongated megasporangium containing a single functional megaspore. Surrounding this were eight fingerlike processes that loosely enclosed the megasporangium. A related species, G. latens, showed these processes fused at the base, forming a cup that more closely covered the megasporangium. These features are important for understanding how early seed plants developed from seedless ancestors.12