Claim: Vittoria Tesi, an Italian opera singer (later singing teacher) of the 18th century who participated in the inauguration of the Teatro San Carlo in Naples in 1737, assuming the travesti title role in Sarro's Achille in Sciro, moved to Vienna the following year, where she debuted in the title role in Gluck's Semiramide riconosciuta, set to a libretto by Metastasio, on the occasione of the inauguration of the new Burgtheater.
Evidence: Vittoria Tesi Tramontini, also known as "La Fiorentina" or "La Moretta" (the Florentine or the Moorish brown girl) (Florence, 13 Feb 1701 – 9 May 1775 in Vienna) was an Italian opera singer (later singing teacher) of the 18th century. In 1737 she participated in the inauguration of the Teatro San Carlo in Naples, assuming the travesti title role in Sarro's Achille in Sciro; in 1744 she performed the title role in Gluck's Ipermestra at the Teatro San Giovanni Grisostomo in Venice and in 1747 she took her leave of Italian audiences appearing at the Naples court and the Teatro San Carlo in the festa teatrale Il sogno di Olimpia by Giuseppe de Majo, opposite Caffarelli, Gizziello and Giovanni Manzuoli. The following year she moved to Vienna, where she debuted in the title role in Gluck's Semiramide riconosciuta, set to a libretto by Metastasio, on the occasione of the inauguration of the new Burgtheater.