Macfarlane Gregory Anthony Mackey (18 February 1942 – 25 January 1997), known professionally as Tony McKay and Exuma, was a Bahamian musician, artist, playwright, and author best known for his music that blends folk, rock, carnival, junkanoo, calypso, reggae, and African music stylings.

His Exuma persona, as well as his lyrics, were influenced by the West African and Bahamian tradition of Obeah, a system of spiritual and healing practices developed among enslaved West Africans in the West Indies, practiced by many on the islands of The Bahamas. He was also a practitioner of herbal medicine. Reviewers have often identified McKay's music as containing or invoking voodoo-related imagery, and have compared his music to that of New Orleans-born musician Dr. John (and vice versa). However, McKay clarified against the association between the imagery of his music and the popular concept of voodoo as depicted in Hollywood-produced films, stressing that his music is instead based on the healing practices of Obeah: "It isn't voodoo or witchcraft [...] not in the way that the man goes home at night and makes a secret potion."

Exuma's self-titled debut album was released in 1970 through Mercury Records, and was followed by Exuma II later that same year. His next four albums, Do Wah Nanny (1971), Snake, Reincarnation (both 1972), and Life (1973), were issued by Kama Sutra Records. In 1977, he created a musical stage production titled Junkanoo Drums that incorporated a number of his songs; the success of the show led to Exuma becoming a regular performer at the New Orleans Jazz & Heritage Festival. By the 1980s, McKay had founded his own record label, Inagua Records, and moved to New Orleans. After moving to Colorado in 1994, he spent time living in Miami, Florida, and Nassau, Bahamas, and died in his sleep in the latter city in January 1997.

In a 1970 interview, McKay, as Exuma, said the "'electrical part' of his being 'came from beyond Mars; down to Earth on a lightning bolt'". He described his music as "all music that has ever been written and all music not yet written. It's feeling, emotion, the sound of man, the sound of day creatures, night creatures and electrical forces".