Chemical signals involved in larval metamorphosis in Hydroides ezoensis (Serpulidae; Polychaeta). Part I: Induction of larval metamorphosis by extract of adult tube clumps

A chemical cue involved in larval metamorphosis of Hydroides ezoensis (Serpulidae; Polychaeta) was found to be contained in the conspecific adult tube clumps, which was expected from their gregarious settlement, Chromatographic fractionation of the MeOH extracts of tube clumps gave an active fraction, designated L3, Fraction L3 Induced metamporphosis in more than 50% of larvae at a dose equivalent to 1 g of the tube clumps. The changes in the metamorphosis rates with larval age after hatching were different between the two metamorphosis-inducing cues, L-3,4-dihydroxyphenylalanine (L-DOPA) and the active fraction, The chemical signal in the active fraction was different from L-DOPA and was concluded to act on a different site of the metamorphic pathway from that of L-DOPA.