Hi all,
Trochidae have a trochophore and then a veliger in their development.
Anyway (as most archaeogastropods) they undergo a lecithotrophic
development, thus with a non-planktotrophic pelagic phase.
It means a relatively short pelagic phase, although one should not
necessarily think in terms of minutes-hours: days, even several days may be
employed to reach metamorphosis.
They don't feed on the phytoplankton, but the larvae can uptake dissolved
organic matter from the sea-water thru the body wall. This is not actually
feeding but is an important issue in their developmental ecology.
=========================================================
Marco Oliverio - Evolutionary Biology PhD
Research Scientist
Dipartimento di Biologia Animale e dell'Uomo
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