Abstract
Ctenophores represent one of the earliest-diverging animal lineages and are distinguished by their exceptional feeding efficiency. The tentacular apparatus of Mnemiopsis leidyi mediates feeding and likely serves diverse sensory roles, yet its structure remains poorly resolved, with conflicting accounts in the literature. Here, we clarify its organization through anatomical and experimental analyses. Light microscopy shows that tentilla bundles arise from a fan-shaped structure previously misidentified as a vestigial principal tentacle. Each tentillum connects directly to the aboral end of the tentacular bulb, contradicting earlier embedding models. Cryosectioning and lesion experiments define the origin and migration of tentilla, while videography reveals fan swaying that bilaterally distributes them. We further show that tentilla can be recycled via entrapment in the transport groove and redirected to the mouth. These findings provide an updated model for understanding tentillar growth, distribution, transport, and recycling within the feeding apparatus.