I was going to suggest macrobrachium (prawns) too. There are many species of macrobrachium, although rosenbergii is the one most commonly used in aquaculture. They are relatively easy to grow. IIRC, rosenbergii is from Madagascar, but there are macrobrachium species that are native to the US,and Central America, and which exceed rosenbergii in size. Some can exceed 2 foot long, including the very long and thin chelae. That size would yield a tail about 6-7 inches long, but not as wide as a lobster. They are catadromous, and very difficult to spawn, but if you collected one, it would be easy to maintain and grow in a large aquarium. The problem with the native ones is that they are very aggressive to each other and eat each other up, so you have to keep them separate in aquaculture, whereas rosenbergii will live together, at least to a higher degree.
These are EXCELLENT eating. I don’t know where you are from, but you can catch them in many of the rivers that run to the gulf in Texas. Somehow they make it above the dam and get into Lake Corpus Christi, too. They are not super abundant, but you can catch them by going to the edge of rockier areas and putting a chicken neck on a string. When the prawn comes to the bait, pull it slowly toward you until you can get a net around him. This is difficult and you have to both stealthy and fast. You can catch them in crab traps too, sometimes, but in Texas it is illegal to run crab traps above the tide line. And below the tide line you will be very lucky to catch one of these.
In Costa Rica, I have caught many wild machrobrachiums (both native and non-native) by taking those termite hives from trees or decaying buildings, dropping the whole thing into a feed sack, then stomping on the bag to break up the hive. Then weight the whole thing with a few rocks or big shell pieces, place in the water in the mangrove areas, and prop the mouth open with a stick. Go back after dark with a flashlight and quickly pick up the sack and sometimes you can get a machrobrachium in it. Low percentage, but worth the effort if they are big ones. Average size yields a tail 4 inches long or so, but you can get bigger ones.
I have raised these in pond aquaculture in Costa Rica, along with tilapia, with some success. But really, I think we got almost as many macrobrachium in ponds we did NOT stock with the things as those we did stock, just because they would come in from the river. They seem to like tilapia ponds a lot. Lots to eat there, I guess.