Yes. Damselflies lay their eggs in water. They hatch and the nymph stays in the water for months Then they emerge as damseflies. i have no idea how it got into your aquarium, but they are voraceous predators. Make sure it is out of there.
I just got some Moscow Blue guppy pairs. I anticipate having fry, but I am not set up yet to take care of them. Suggestions for a tank, substrate, and a filter that won't suck them up as detritius? Thanks! New to the hobby.