It is strange. When I grab one they shrink into the shell/exoskeleton. I can pinch the tip a little and it feels like plastic. If it is a shell they made from their environment all there ones I've seen have the same source. When they swim it does look like it's a kind id worm inside the shell. I've attached a picture of one in the shell.
It's not a damselfly larvae or Dragon fly larvae. They don't look like that.
Have you caught it yet?
If you catch it, see it the long green part is a plant the larvae is hiding in.
If you can separate the green part from the larvae, it's a caddis fly.
Now I'm all curious to find out what it is.
Well, I’m not sure that he babies are half size. They are probably around 1/4-1/2.” Everyone is healthy, and I’ve been able to count 9 babies at one time. Hoping the now 3 new mamas drop soon! Eggs still look fairly brown.