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".
Superwoman
When Superman died, Lana Lang and Lois Lane both absorbed energy released from his body and the two women developed superhuman powers. Lana gained the power to convert solar radiation into various forms of electromagnetic energy, while Lois developed powers similar to Superman's. Both Lana and Lois became Superwoman. After Lois' death, Lana became the sole Superwoman.