Members of the family are found worldwide and many live largely buried in soft substrates with only their oral disc and tentacles protruding.
The base is often rounded and used for digging but in some species it is flattened and adhesive to small objects.
At least six pairs of the mesenteries are perfect, reaching from the base as far as the actinopharynx or throat of the anemone.
There is a single, well defined siphonoglyph, a ciliated groove, which is often elongated and nearly detached from the rest of the actinopharynx.
[2][3] According to the World Register of Marine Species, the family includes the following genera:[4]