1. Muriel Salina Costa-Greenspon was an American mezzo-soprano who had a lengthy career at the New York City Opera from 1963 to 1993.

1. Muriel Salina Costa-Greenspon was an American mezzo-soprano who had a lengthy career at the New York City Opera from 1963 to 1993.
Muriel Costa-Greenspon portrayed a gallery of character roles that extended from twentieth-century works by Leonard Bernstein, Benjamin Britten, Carlisle Floyd, Lee Hoiby, Arthur Honegger, Gian Carlo Menotti, and Douglas Moore, to the contralto heroines of Gilbert and Sullivan, and comic scene-stealers by Puccini, Mozart, and Donizetti.
Muriel Costa-Greenspon attended Cass Technical High School and later to the University of Michigan, Ann Arbor, where she earned bachelor's and master's degrees in vocal performance.
Muriel Costa-Greenspon studied voice under Joseph Blatt at the University of Michigan and later with Sam Morgenstern in New York City.
Muriel Costa-Greenspon made her professional debut with the Detroit Grand Opera Association at the Detroit Opera House as Miss Todd in The Old Maid and the Thief in 1960.
Muriel Costa-Greenspon participated in some of the company's landmark productions of the 1960s and 1970s, including Frank Corsaro's La traviata, as well as Tito Capobianco's production of Le coq d'or and Corsaro's Faust, both opposite Beverly Sills and Norman Treigle.
Muriel Costa-Greenspon took on leading roles for NYCO in the American premieres of Prokofiev's The Fiery Angel and von Einem's Dantons Tod, and the 1964 world-premiere of Hoiby's Natalia Petrovna.
Muriel Costa-Greenspon portrayed Madame Flora, and Sal Mineo both directed and took the part of the mute, Toby.
Menotti, who was an admirer of Muriel Costa-Greenspon, later invited her to sing Madame Flora at the Spoleto Festival in 1975.
In 1995, Muriel Costa-Greenspon made her only appearance at the Metropolitan Opera, as the Duchesse of Krakentorp, a speaking role, in La fille du regiment with June Anderson as Marie and Luciano Pavarotti as Tonio.
Muriel Costa-Greenspon died on December 26,2005, aged 68, in New York City.
Muriel Costa-Greenspon's death was due to natural causes, according to her son, Stefano Costa, who, along with her husband, Giorgio, were her immediate survivors.