What the heck is this?

I'd just keep an eye on the tank and pluck them out when you see them... at 1/3" thats very tiny and if you remove some of your plant cover I'd agree your mollies would likely go for them.
 
damselfly larva

I would love to see damselfly larva in my outside pond. Is the only problem eating little fish? My fish are all over 4 inches out there.
 
HOB

I think the mollies would eat them if they found them, but the floating plants are really dense. There is a cover on the tank, it would have had to come in around the HOB. I may tray removing some of the plants and see it that would make them "more available" to the fish. I don't see anymore on first glance, but since this is the second, I assume there are more (unless the fish DID eat them........)

What is HOB?
 
They struggle to eat anything bigger than fry. Dragonfly larvae possibly could take small neons, but not damselfly larvae. The only insect larva which would worry me in an aquarium would be the Great Diving Beetle larva, aka the Water Tiger. It's venomous so can take much larger prey.
 
Right on, Karl. I've seen water tigers take down 2" long sunfish and pirate perch. Some of the bigger dragonfly naiads, like darners, can also take fairly large prey. But damselflies are harmless to most adult fish; they mainly feed on microcrustaceans and midge larvae.

Jack- you may well have damselflies already. They are pretty well camouflaged and tend to cling to plants. If you've seen this going on around your pond:

Damsels1.jpg


then you can be pretty sure there are damsel naiads in the pond.
 
^ I see that scene around my pond almost every day but instead with dragonflies. After mating, one of the dragonfly start to dip their tails in the water while hovering about 3 inches above it. The eggs are white and about the size of sand grains, with a jelly like covering around them. You don't want to see that if you're trying to raise baby goldfish. Luckily, the big goldfish take care of that as soon as the dragonfly hatch.
 
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