Eyelash worms get a makeover: integrative taxonomy of Myxicola (Sabellidae) reveals four new species in the Mediterranean Sea and a novel genus

Taxonomists in the 19th and early 20th centuries described several species of Myxicola Meneghini, 1847 in Europe. Until recently, all historical taxa were considered synonyms of M. infundibulum. Using an integrative taxonomic approach—combining molecular phylogenetics and morphological re-evaluation of museum samples, and newly collected material from the Mediterranean Sea and Macaronesia—we uncovered significant diversity within this genus. Phylogenetic analyses based on three molecular markers reveal that Myxicola comprises two highly supported and deeply divergent clades. The morphological synapomorphies unique to one of these clades, reported for the first time for Sabellidae as a whole, led to the establishment of Paramyxicola gen. nov. We confirm the distinction of M. cosentini and M. giuliae from M. infundibulum, while M. cataldoi is identified as junior synonym of M. infundibulum. We describe two new species of Myxicola (M. albertoangelai sp. nov. and M. pirainoi sp. nov.) and two new species of Paramyxicola (P. mariacristinae sp. nov. and P. marielouisae sp. nov.). We synonymize M. polychroma with M. modesta and report it, together with M. cf. fauveli, in the Mediterranean Sea for the first time. The biogeography and distribution of species in these genera are discussed, with emphasis on their possible evolutionary history.