The feeding end can be packed awaySourced
Peanut worms retract their narrow front section
Marine sipunculans have a narrow anterior section called the introvert, with the mouth at its tip. They extend it to collect food and can retract it into the wider trunk when conditions are unsuitable or danger threatens.
The feeding end need not stay extended.
Summary / translation: Unbubly · CC BY-SA 4.0
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Sipuncula · Wikimedia contributors
Adapted, summarized and translated from the source. Adapted text is also available under CC BY-SA 4.0.
Reviewed: 2026-10-05