they do indeed, many representatives of the main FW shrimp families (atyidae and paleomonidae) have many representatives there, they are just relatively rare. however, I have heard that amazonian ghost shrimp (im unsure of the scientific name) are occasionally avalible. id reccomend checking out petshrimp.com for more info. im also pretty sure that the vampire srimp, a filter feeding rewlative of the bamboo/wood shrimp, is also native to south america as well as tropical africa. once again petshrimp.com will be able to answer that for certian. petshrimp.com is also a good place to buy shrimp, as well as aquabid; I hear that arizona gardens has a large selection, but ive heard many bad reviews about them.