Annelida Lamarck, 1809 - segmented worms "polychaetes" see Class Polychaeta Grube, 1850 Scolecida G.W. Rouse & K. Fauchald, 1997 see Order Scolecida Rouse & Fauchald, 1997 Family Capitellidae Grube, 1862 Genus Mediomastus Hartman, 1944 Mediomastus fragilis Rasmussen, 1973