Yacuruna
Yacuruna (Quechua: 'water people') are hairy, deformed-footed aquatic beings who inhabit upside-down underwater cities in Amazonian rivers. They abduct humans (especially menstruating women) by transforming into pink river dolphins or handsome men, using aphrodisiacs. Victims gradually transform into Yacuruna. Shamans summon them as familiars for healing knowledge.