Meeting Abstract
Slipper limpets use different ciliary feeding mechanisms as a larva and as an adult. Before metamorphosis larvae of Crepidula fornicata developed the ctenidial (gill) filaments that produce the feeding current and the radula that aids ingestion in the postlarval feeding mechanism, but ctenidial feeding did not begin either in the larval stage or immediately after loss of the larval feeding apparatus (velum) at metamorphosis. Delay of settlement in the absence of a stimulus resulted in earlier postmetamorphic feeding. When younger larvae were induced to metamorphose, the juveniles began ctenidial feeding in about a day after metamorphosis. When older larvae were induced to metamorphose, juveniles began ctenidial feeding in a few hours after metamorphosis. Ctenidial feeding was recorded for juveniles attached to a coverglass, ventral side upward. In their first feeding, juveniles formed a food cord from phytoplankton caught on mucous strands, transported it to the mouth, and grasped it with the radula. Ctenidial feeding by juveniles resembled feeding by adults, except that there was no distinct food canal in the path from ctenidial filaments to the mouth. The juveniles became sedentary soon after metamorphosis and were not observed to feed by scraping the substratum with the radula, in contrast to the first feeding by juveniles of another Crepidula species, observed by Montiel et al. (2005).