In a given ecosystem one dominant species goes extinct in order to have the largest on the ecosystem what type of food Web role would this species have filled?

The dominant species that goes extinct likely filled a keystone species role, which is crucial for maintaining the structure and balance of the ecosystem. Keystone species have a disproportionately large impact on their environment relative to their abundance, often influencing the types and numbers of other species in the food web. Their extinction can lead to significant changes in community dynamics, potentially resulting in the decline or proliferation of other species and altering habitat structure.