A trochophore is a type of free-swimming planktonic marine larva with several bands of cilia. By moving their cilia rapidly, they make a water eddy to control their movement, and to bring their food closer in order to capture it more easily.

[The anatomy of a trochophore

A - episphere B - hyposphere 1 - ganglia 2 - apical tuft 3 - prototroch 4 - metatroch 5 - nephridium 6 - anus 7 - protonephridia 8 - gastrointestinal tract 9 - buccal opening 10 - blastocoele | upload.wikimedia.org/wikipedia/commons/b/b4/Trocofora.svg]

Occurrence

Trochophores exist as a larval form within the trochozoan clade, which include the entoprocts, molluscs, annelids (including echiurans and sipunculans) and nemerteans. Together, these phyla make up part of the Lophotrochozoa; it is possible that trochophore larvae were present in the life cycle of the group's common ancestor.

Etymology

The term trochophore derives from the ancient Greek, meaning "wheel", and — or —, meaning 'to bear, to carry', because the larva is bearing a wheel-shaped band of cilia.

Feeding habits

Trochophore larvae are often planktotrophic; that is, they feed on other plankton species.

Life cycle

The example of the development of the annelid Pomatoceros lamarckii (family Serpulidae) shows various trochophore stages (image: D-F): D - early trochophore ; E - complete trochophore ; F - late trochophore ; G - metatrochophore.