I netted them in a shallow brackish puddle around a drainage in my neighborhood in Virginia. I’m pretty sure they are Gambusia but I didn’t know they could thrive in brackish. I know it’s brackish because the river kind of feeds into and we will get eels, mud minnows, and other brackish water fish in it. I threw them in a 10 gallon and they don’t seem to be dying so that’s good. I think I’ll breed them for fun because I’ve got nothing better do right now as far as fishkeeping goes.