The other closely related species is found in the green river system in Kentucky, I believe. It is called the Bottlebrush crayfish, due to its feathery antennae. These frequently reach 10 inches in length. They are difficult to collect, as they are also found under large rocks in deeper portions of the river. I personally know several people who have collected them while sampling. They say that they are amazing. I plan to take a trip down there this year, and collect a handful, and try my luck at breeding them. Might be a viable aquaculture species. Might be more viable in temperate climates than the Australian giant crayfish species. I happen to have a Kentucky scientific collectors permit, so there are no legality issues. Just not allowed to touch federally listed species. Have to wonder how they would fare in a pond.