Three ayahuasca religions were founded in western Brazil inside about twenty five years, in the same small region, among people of similar background, and all three by Black Brazilians of north eastern origin. Because the sacrament is shared and the founders knew of one another, outside accounts sometimes present the Barquinha as a branch of Santo Daime. It is not held that way here, and it is not held that way by the people in it, who describe the three as separate religions rather than as denominations of one thing.
The atlas follows that reading for a reason that goes beyond deference. The three differ on the questions a tradition is actually organised around. Santo Daime works through a growing corpus of received hymns sung in uniform in a fixed order. The Uniao do Vegetal has no hymnal of that kind at all, and doctrine is delivered orally by a master answering questions. The Barquinha keeps the hymns and then adds the Catholic festival calendar, the incorporation of spirits and the charitable mission, none of which is a variation in emphasis. Movement between the three is uncommon.
What the Barquinha does not have is reach or a literature. It remains small and concentrated in Acre while the other two have congregations abroad, and most of what has been written about it is recent Brazilian scholarship with little in English. That imbalance is worth naming, because it is the reason a tradition that any specialist treats as one of three is the one a general reader has never heard of. The atlas describes it, as it describes any living tradition, without instructing anyone in it and without recommending it.