The American slipper limpet Crepidula fornicata (Linnaeus, 1758) is a recent invader in the Ria de Aveiro coastal lagoon, with the first occurrence reported in 2014. This alien species, native to the Atlantic coast of the United States of America, is relatively abundant in northern European coast, where it has been reported to have caused several environmental and economic impacts. Portugal is the southern limit of its current distribution in Europe but the species presence and dynamic is yet poorly described. The CREPIDULA project will contribute to understand the invasion process and current stage the American slipper limpet Crepidula fornicata (Linnaeus, 1758) populations in the Ria de Aveiro coastal lagoon, located in the Atlantic North West coast of Portugal. To achieve that it will focus on several aspects and lines of evidence, namely the species characteristics, the local introduction history, the invaded niche, the life-cycle, and the local impacts on biodiversity and ecosystem services.