Scissurellidae

Scissurellidae is a family of small to minute sea snails, marine gastropod mollusks. These snails are characterized by their thin, often transparent shells which are typically helicoid, meaning they are coiled in a spiral. A defining feature of Scissurellidae, and indeed the family's namesake, is the presence of a slit or hole in the shell, known as a selenizone or slit band. This slit is a unique characteristic among gastropods. The shells of scissurellids are usually dextral, coiling to the right, although sinistral coiling can occasionally occur.

The family is found worldwide, inhabiting a variety of marine environments, but they are most commonly encountered in temperate and tropical waters. They are often found in benthic habitats, living on the seabed, and can be associated with algae, sponges, or other sessile invertebrates. Their diet typically consists of microorganisms, such as algae or bacteria, which they graze from surfaces.

Scissurellidae are a diverse group, with numerous genera and species described, though many are still poorly understood. Their small size and preference for cryptic habitats can make them challenging to find and study. Despite their widespread distribution, they are not considered commercially important, but they play a role in the broader marine ecosystem as grazers and as a food source for other small invertebrates.