Philinidae
Philinidae is a family of small, predatory sea slugs, commonly known as bubble shells or philine snails. They are marine gastropods in the superfamily Runcinoidea. These are shell-less, or nearly shell-less, nudibranchs, with only a small, internal shell, or none at all. Philinids have a distinctive morphology with a distinctive mantle that is not present in most other nudibranchs.
Common Names
Philinids are commonly called "bubble shells" due to their translucent, bubble-like appearance. They are also sometimes referred to as "philine snails."
Characteristics
Philinids are small, typically less than 10 mm in length. They have a distinctive body shape that is more or less ovoid. Unlike most nudibranchs, philine snails lack a cerata, the soft, finger-like projections on the dorsal surface. Instead, they have a distinct, fleshy mantle that often covers the head and has a distinctive shape. These animals are known for their translucent bodies that often have a slightly bluish, greyish, or whitish coloration. They lack a well-developed radula, but have a long, extensible proboscis that is used to capture prey.
Environment
Philinids are found in a variety of marine environments, including shallow coastal waters, intertidal zones, and the open ocean. They are particularly common in sandy and muddy habitats, where they feed on small invertebrates, such as polychaete worms, foraminiferans, and other small mollusks. They use their proboscis to capture prey by sucking the contents out of their shells. Philinids are important components of marine ecosystems, contributing to the food web and playing a role in the regulation of populations of their prey.
References
For further information on Philinidae, please refer to the following reliable sources: