The following taxon apparently lies within the circumscription of Caulerpa serrulata but has not yet been transferred or reduced to synonymy:
Caulerpa freycinetii C. Agardh forma longidentata Weber-van Bosse, 1898: 314–315 ("var. typica'' forma `longi-dentata') (type locality: "Côte orientale de Malacca'').
INDIAN OCEAN DISTRIBUTION: Malaysia.