This drawing by Leonardo da Vinci was rediscovered in the 19th century and was immediately assumed to be a self-portrait. This is no longer thought to be true.
This sketch dates from the 1490s, when Leonardo would only have been in his forties. No one is even sure that Leonardo had a beard until his later years.
Compare with a portrait of da Vinci by Francesco Melzi.
Leonardo was certainly interested in the features of old people. He drew them many times during his career. This was unusual at a time when most artists were solely interested in painting beauty.
The original work is held by the Biblioteca Reale in Turin.