Help with ID?

[Aquaexploder]

Well, I have some sad news.
They were all doing fine until this morning. I woke up and found that overnight something killed all the ants, queen included. They were in a covered outworld with water and food and I did by best to keep temperatures around where umbartus enjoy, they had pantyhose stretched across the top as a 'lid' because they could slip out of everything else but they still had ampule aeration, but evidently I did something wrong. I've heard somewhere before that the lasius species has a habit of suddenly dying on keepers for some unknown reason, so maybe that's what did it. I'm kinda sad now.

I feel so bad and I wish you the best of luck.