A pollen development stage (PO:0001007) during which the generative cell (PO:0020097) undergoes mitotic division to form two male gametes, the pollen sperm cells (PO:0025121). [source: POC:Laurel_Cooper, TAIR:Katica_Ilic]
Comment
In taxa with mature two-celled pollen (PO:0025281), the second mitotic division takes place after pollen germination (GO:0009846), in the germinating pollen tube cell (PO:0025195). Note: This term overlaps with the GO BP term: generative cell mitosis (GO:0055047): The process in which the generative cell divides by mitosis to form two haploid cells. These will subsequently differentiate into sperm cells.