A leaf that bears sporangia (spore-producing structures). In ferns the sporophylls are the normal foliage leaves, but in other plants the sporophylls are modified and arise in specialized structures such as the strobili (cones) of clubmosses, horsetails, and gymnosperms and the flower of angiosperms. Most plants produce spores of two different sizes (small microspores and large megaspores). The sporophylls bearing these are called microsporophylls and megasporophylls respectively.