The Solenogastres (less often referred to as Neomeniomorpha), commonly known as solenogasters, are a class of small, worm-like, shell-less molluscs (Aplacophora), the other class being the Caudofoveata (Chaetodermomorpha).

Some recent literature and recent molecular evidence, indicates that the Aplacophora may be polyphyletic, and therefore some taxonomists may divide Solenogastres and Caudofoveata into separate classes.

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