Eustochia Smeralda Calafato was a 15th-century Italian saint and a member of the Order of the Poor Clares. Born in 1434 near Messina, she entered religious life at fifteen despite opposition from her family. Known for her intense devotion and strict adherence to poverty, she eventually established a new convent called Montevergine. She served as its abbess until her death in 1485. Today, she is recognized as a co-patroness of Messina, where her religious legacy remains significant.