A sea snail that lives near hydrothermal vents thousands of feet below the ocean surface has a unique solution to navigating such a volatile home: It builds itself an armored shell out of iron.
The scaly-foot snail (Chrysomallon squamiferum), also known as the sea pangolin for its tough plates, is known to inhabit only three locations near hydrothermal vents in the Indian Ocean. Prior studies suggested that the snails' metal armor provides defense against predators and rival snails near these vents, which spew scaldingly hot, mineral-rich water.
On July 18, the International Union for Conservation of Nature (IUCN) listed the sea pangolin as endangered. As the first animal species to be assigned that status due to deep-sea mining, it was a "notable" addition to the list, IUCN representatives said in a statement.
Scaly-foot snails, first discovered in 2003, inhabit an area roughly the size of two American football fields, and live at depths of up to 9,500 feet (2,900 meters).
The mollusk's shell consists of three layers: a calcified inner layer, an organic middle layer, an outer layer fortified with iron sulfides, MIT News previously reported. The snails also have enormous hearts, in part to accommodate the oxygen needs of symbiotic bacteria that live in their bodies and provide most of their nutrition.
Little is known about these snails' habits and biology. However, just because they've evolved to survive in a volatile hydrothermal environment doesn't mean that the snails could weather severe disruption caused by seabed mining.