Each fertile shoot is composed of two fused bracteoles, which surround the microsporophyll. |
The microsporophyll of Lepidopteris has been reconstructed as a pinnate axis with short branches bearing clusters of small elongate pollen sacs fused at the base. |
In contrast, C. comptonensis microsporophyll heads have a cutinized hypodermis, and distinctly conical epidermal papillae with pointed apices. |
Isoetes is heterosporous, with each leaf a potential microsporophyll or megasporophyll. |