Afrânio Pompílio Gastos do Amaral (1 December 1894 in Belém – 29 November 1982 in São Paulo) was a Brazilian herpetologist.
As a youngster, he collected snakes for Augusto Emilio Goeldi (1859-1917).
He studied medicine in Salvador, Bahia, later finding employment at the Instituto Butantan in São Paulo.
Here, his work involved research and production of anti-venom serum.
In 1921 he succeeded Vital Brazil (1865-1950) as director of the Instituto Butantan.
During his career, he was the author of over 450 published works.