Costantino Cattoi (1894-1975) was an officer in the Italian Air Force during the First World War, during which he developed the cartographic value of aerial photography. In 1955 he got considerable media coverage for his concept of lost civilisations, which included Lemuria, Mu and Atlantis in the Indian, Pacific and Atlantic oceans respectively. He also posited an extension of Atlantis reaching into the Mediterranean as far as Italy and added his view that just offshore from Ansedonia, 70 miles north of Rome, may have been the location of the Atlantean capital!
Cattoi also announced that he had located three of the cities of Tirrenide between Porto Santo Stefano and Isola del Giglio, but he died without being able to find funding for the underwater exploration that would have proved his hypothesis(b).
(a) https://news.google.com/newspapers?nid=1350&dat=19550605&id=H7lOAAAAIBAJ&sjid=kAAEAAAAIBAJ&pg=5424,765131&hl=en (Toledo Blade Pictorial, June 5, 1955)
(b) See: https://web.archive.org/web/20190414214546/http://www.tuttomisteri.it/tirrenide/ (Italian)*