Female, I also saw another female and a male (https://www.inaturalist.org/observations/155157187) in the same garden pond.
The pond is filled with larvae of all ages. Same pond (and probably offspring of): https://www.inaturalist.org/observations/155157187 and https://www.inaturalist.org/observations/155157043)
Larvae count has decreased by a significant amount - Probably due to cannibalism and predation by dragonfly larvae. Most larvae have already achieved lengths of 3-4 cm.
I could also observe 1 adult male and 1 adult female in the pond.
Same pond as: https://www.inaturalist.org/observations/166816709