Which larval form of mollusk is known for swimming freely using cilia?

The trochophore larval form is characteristic of many mollusks and some annelids. Trochophores are recognized for their distinctive shape and are equipped with a band of cilia around their body. This ciliary band enables the larvae to swim freely in the water column, allowing for better dispersal and access to different habitats.

During its early stages, the trochophore larva undergoes vital processes such as growth and development, and the cilia play a crucial role in both locomotion and feeding. In contrast, other larval forms like gemmules, scoleces, and proglottids do not have the same swimming capabilities or ciliated structures that define trochophores. Gemmules are actually structures related to asexual reproduction in certain sponges, scolex refers to the head segment of a tapeworm, and proglottids are segments of a tapeworm's body. Each of these serves distinct functions unrelated to free-swimming larval forms.