A recent deep-sea expedition off the coasts of Chile and Peru is revealing the secrets of a vast underwater mountain system — and making the strongest case yet for greater protections there. Using underwater robots capable of descending more than 4,500 meters (14,760 feet), researchers say they may have discovered more than 100 never-before-seen species living on the Salas y Gómez and Nazca ridges, which stretch across the southeastern Pacific. “These findings just blew us away,” said Erin Easton, the expedition’s lead scientist. “It was almost baffling to discover so many new creatures. In some areas, we were finding species we’d never encountered before every few meters.” The creatures include cactus urchins — of which there is currently only one known species — squat lobsters with spiky shells and beady eyes, ancient corals likely dating back thousands of years, translucent “glass” squids and potentially 30 new species of sea sponges, including some unusually colorful ones.…