The Afro-descendents of Panama’s Caribbean coast maintain the tradition of the Negros Congos, a series of folkloric manifestations occurring during Carnival season, and including a special cryptolect based loosely on Spanish. According to oral tradition, Congo speech was devised among captive and maroon Africans in colonial Panama as a means of hiding their speech from their colonial masters. Widely felt — both by Congo participants and by outside observers — to consist only of deliberate deformations of Spanish words and semantic inversions, Congo speech in reality also contains numerous elements traceable to Afro-Hispanic communities in other former Spanish-American colonies. Data drawn from twenty-four Congo communities demonstrate systematic regional variation — phonetic and lexical — that verifies the status of Congo speech as a cryptolect undergoing natural language evolution. These data also contribute to the search for the geographical locus of the original Congo dialect.