Gender in speculative fiction
The first known female superhero is writer-artist Fletcher Hanks's minor character Fantomah, an ageless, ancient Egyptian woman in the modern day who could transform into a skull-faced creature with superpowers to fight evil; she debuted in 1940 in Fiction Houses "Jungle Comics".
Superhero
The Marvel Comics teams of the early 1960s typically included at least one (and often the only) female member, much like DC's flagship superhero team the Justice League of America (whose initial roster included Wonder Woman as the token female); examples include the Fantastic Four's Invisible Girl, the X-Men's Jean Grey (originally known as Marvel Girl), the Avengers' Wasp, and the Brotherhood of Mutants' Scarlet Witch (who later joined the Avengers).