Unfinished symphony: updating the systematics of Aeolidiidae (Nudibranchia, Gastropoda), with special focus on Aeolidiella Bergh, 1867

Abstract

This paper updates the systematics of Aeolidiidae (Heterobranchia, Nudibranchia), with special emphasis on the genus Aeolidiella Bergh, 1867. Up to now, Aeolidiella was composed of five valid species: A. alderi, A. glauca, A. rubra, A. sanguinea from the Mediterranean Sea and the Eastern Atlantic and A. drusilla comb. nov. from the Pacific Ocean. To clarify the systematics of this genus we present an integrative approach based on molecular and morphological data, literature review, species delimitation approaches, and haplotype network analysis. Aeolidiella glauca was recognized as a species complex resulting in the description of Aeolidiella avatar sp. nov., whereas the nominal name A. rubra is considered nomem dubium. The species Aeolidiella drusilla comb. nov. is ascribed to the new genus Novaeolidiella gen. nov. together with the new species Novaeolidiella janae sp. nov. from the Philippines. This restricts the genus Aeolidiella to the Atlantic Ocean and Mediterranean Sea.