Which gruiform birds eat large snails as their main food?

Within the order Gruiformes, the limpkin (Aramus guarauna) is the bird most notably specialized for a diet consisting chiefly of large snails.12

In regions such as the Florida Everglades, the limpkin feeds primarily on large, greenish, freshwater snails (Ampullaria). To access the snail, the bird carries it to a favorite feeding perch or its nest, holds the shell firmly with one foot, and strikes it with its bill. It then forces its bill into the shell's spiral opening to extract the snail. These feeding stations are often identifiable by the presence of telltale piles of broken shells.12