https://en.wikipedia.org/wiki/Hyalella_azteca
This is a forage critter that I hadn't heard of before. It's described as being common in North America, but its numbers are declining. It appears to be in about the same place in the food chain as scud and close to grass shrimp. I don't know if it has a common name. If I could get some, I'd put them in my pond. I'm wondering if anyone has info on these, and if they have been discussed previously on the Forum.