Can encapsulated embryos of crepidula fornicata (L.) use extracapsular dissolved organic matter? an experimental study with a 13 C-enriched amino acid
Date
2012Author
Leroy, Fanny
Comtet, Thierry
Brante, Antonio
Leroux, Cedric
Riera, Pascal
Publisher
Journal of Molluscan StudiesDescription
Artículo de publicación ISIMetadata
Show full item recordAbstract
Many marine gastropod species brood their embryos in thin-walled capsules to protect them during
development. Despite its beneficial effects, encapsulation has two major constraints, nutrition and
oxygen supply, which affect embryo development and larval survival. Developing embryos usually
rely on intracapsular food sources provided by the mother, in the form of yolk, nurse eggs and intracapsular
fluid. However, it is still not clear if they are able to feed on extracapsular sources that may
cross the capsule wall. We investigated this possibility in the calyptraeid species Crepidula fornicata. In
this species, the internal capsule wall thickness sharply decreases during embryonic development,
which might change wall permeability to small organic molecules, thus providing embryos with external
dissolved organic matter. To test this hypothesis, encapsulated and excapsulated embryos of C.
fornicata were placed for 48 h in a 13C-enriched amino acid (L-alanine) solution. Excapsulated
embryos were enriched in 13C (þ5.75‰), which suggested that they were able to assimilate the labelled
amino acid. In contrast, encapsulated embryos were weakly enriched (þ0.75‰), suggesting
that encapsulation greatly reduces the potential for the use of extracapsular amino acids and that
encapsulated embryos mainly rely on maternal food.