Lockshells
The Lockshells are a large genus descending from the Shutshell, consisting of hundreds of species. They are predominately planktivores but larger species will also catch fauna and flora with their four arms and bring them into their blind gut for digestion. Their arms are lined with small hairs coated in a paralytic film which can incapacitate small fauna on contact, allowing them to consume fauna near their own size without much risk of harm.
They are hermaphrodites, releasing spores en masse to then enter the water column. The timing of spore release and other stages of their life cycle vary between species. Spores are released on a 5 to 20 day cycle, usually synchronized to the release schedule of neighboring Lockshell individuals of the same species. These spores will transition into their motile larval stage anywhere from 3 to 21 days from release. The spores themselves are very resilient, and will enter a dormant stage whenever the condition of the water changes rapidly. This dormancy can last for up to 6 months, and in temperate and polar seas serves as a means to overwinter outside of their vulnerable larval stage. This larval stage can live anywhere from 7 to 10 days, with its main purpose being to find a suitable location to anchor itself and transition into its adult stage.
This anchoring location depends on the species, as each has adapted to settling on different supports. Some species anchor themselves to exposed rock along shorelines, while others anchor onto the various crystal flora. Some species will even anchor onto the hard surfaces of fauna, including their distant relatives the Nautstars and Roths. They are common throughout all marine sunlight waters. Species living in tidal zones have particularly tightly locking shells, such that they can keep a small reservoir of water inside their shells during low tide. They are able to close their shells incredibly quickly, such that the impact of the shells against one another creates an audible clicking sound akin to a padlock closing. Rocky beaches tend towards the lowering tide being marked by sporadic faint clicking from the rock pools as they dry out.