Came home today and went to go do my WC, and as I was getting ready noticed one of my females acting nuttier than squirrel doo. She was snapping in every direction trying to get away from what I originally thought was just a molt.
By the time I grabbed my net and fished her out I found out what it was. Being only about .5" long was good enough to take down a healthy 1" female. I didn't get any pictures of it at the time as I honestly took a little bit of aggression out on it after I quickly relocated the other shrimp. I don't have a clue how THAT got in there, as I am very anal about inspecting everything in a quarantine container for 24 hours minimum with bright lights.
Diving Beetle Larvae. Enough said. I basically nuked the tank and tossed anything that was in it, out. Not in the mood to play that game.
Predaceous diving beetle larvae. Not a dragonfly larvae.
I'm doing my senior research on them. In a study, they were found to be able to consume ~40 tadpoles in a day
Your research is spot on. I have an older cinder block pool on the property I haven't got around to dozing in. Right now the thing is full of tadpoles from Green Tree Frogs, Southern Cricket Frogs, Green Frogs, Toads and probably 10 other amphibians. Last week I was out attempting to trim back the overgrowth in there and watched a tadpole get destroyed by one of these (thus why I know what they are). That one was over an inch long and took down a legged, but still full-tailed, Cricket Frog tadpole.
I also noticed that pool has probably millions of pond snails and bloodworms (midge larvae)
The only thing that comes to mind is my 7 year old boy, and it would be futile at this point to attempt to "extract" the information from him.
Other possibility is that an adult flew into the house one night following light sources, only landed in that one tank (out of the 7 over there) and left without a trace after leaving it's hellspawn. I just searched the windowsills for a dead adult and came up with nothing.
Either way all tanks are all being covered from now on to prevent either possibility from occurring again.
Beetle larvae! Never would have guessed, haha. Cool how similar they look to damsel fly larvae. Yeah, I remember the first time I picked up a dragonfly larvae here in my pond... Big mistake, that sucker took a chunk out of my finger! That looks like it would do something similar