Which stage of the lycophyte life cycle produces sperm and eggs?

In the life cycle of a lycophyte, the stage that produces sperm and eggs is the gametophyte.12

Lycophytes exhibit an alternation of generations between a spore-producing phase, known as the sporophyte, and the sex-cell-producing gametophyte phase. Within the gametophyte, specialized structures called antheridia produce sperm, while archegonia produce eggs.1

Depending on the specific genus, these gametophytes may be bisexual—bearing both antheridia and archegonia on the same plant—or, in heterosporous genera like Selaginella and Isoetes, they may develop as separate male (microgametophyte) and female (megagametophyte) structures.1