The occurrence of an area of methane seepage of Chile is reported for the first time. Shell fragments of two species of bivalves of the genus Calyptogena and one species of Acharax were retrieved in dredge hauls from 651 to 934 m depth of Concepción (*368S). A large quantity of carbonate blocks was also collected, indicating anaerobic oxidation of methane in the sediment. The accompanying, non-chemosynthetic fauna from one of the hauls was diverse, containing some species new to science. Our preliminary data suggests an assemblage similar in structure to those reported elsewhere, albeit with an important endemic component.