Shell-boring species of the genus Polydora present a growing threat to the sustainability of shellfish aquaculture in Korean coastal waters. As one of the world’s leading producers of shellfish, Korea is especially vulnerable to the economic and ecological impacts caused by these polychaete annelids. Polydora species penetrate the calcareous shells of commercially valuable mollusks such as oysters, mussels, scallops, clams, and abalone. Their burrowing compromises shell integrity, reduces growth rates, increases susceptibility to secondary infections, and significantly lowers the market value of infested shellfish. This review synthesizes current global knowledge on shell-boring Polydora species, with a focus on those reported from Korean waters. Emphasis is placed on diagnostic morphological characteristics, reproductive biology, host associations, and taxonomic identification. Special attention is given to molecular advances, particularly the use of mitochondrial cox1 and nuclear 18S rRNA gene markers for species-level resolution. The review evaluates the implications of Polydora infestations for aquaculture operations, discusses available detection and mitigation strategies, and highlights critical knowledge gaps, especially the lack of standardized histological methods for observing gonadal development. By integrating insights from both classical and molecular studies, this review aims to inform targeted management strategies and guide future research on this economically significant group of shell-boring polychaetes.
Jayaweera et al. (Wed,) studied this question.