Marcos Mundstock, (born May 25, 1942) is an Argentinian musician, writer, comedian, and former broadcaster and copywriter.
Born in Santa Fe, Argentina, he is best known as a founding member of Les Luthiers, their emcee, and writing many of their shows and lyrics.
He also invented one of their most famous instruments, the gom-horn (a trumpet parody) and occasionally played keyboards and percussion for their numbers.
Mostly, his role is that of the 'non-musician' member, in spite of having sung for their (mostly operatic) pieces with some frequency.