Samuel Edward Wright  (November 20, 1948 – May 24, 2021) was an American actor and singer. He was best known as the voice of  Sebastian  in  Disney 's  The Little Mermaid , for which he provided the lead vocals to " Under the Sea ", [1]  which won the  Academy Award for Best Original Song . He played  Dizzy Gillespie in the  1988 biographical film  about  Charlie Parker . Wright also played the part of  Mufasa in the original cast of  The Lion King  on Broadway and voiced Kron the  Iguanodon  in Disney's 2000  CGI /live-action film  Dinosaur