The risk of the nudibranch Baeolidia rieae (Mollusca: Gastropoda: Heterobranchia) in the international aquarium trade

Baeolidia rieae Carmona, Pola, Gosliner & Cervera, 2014 was described based on a single specimen from the subtropical Amami-Oshima Island (SW Japan). In this study, we recorded B. rieae feeding on a zoantharian, Zoanthus sp., in an aquarium store in Barcelona (Spain). The morphological and molecular match from the original description corroborated its identification. We discuss the possible origin of the B. rieae in aquarium stores, its resistance to ordinary disinfection processes, the harm it may cause to commercial coral species, and how it might develop into an invasive species if it continues to be found in aquarium stores around the world without treating the problem properly. Finally, we describe for the first time the spawn of B. rieae and its eggs features, and provide new morphological and biological data.