SEM photomicrographs of the body wall ossicles of Eupentacta species A–D E. quinquesemita, Mendocino, California (holotype, Museum of Comparative Zoology at Harvard University) A basket B knobbed plate C fenestrated hollow ellipsoid D very large scale-like multilayer plate E, F E. pseudoquinquesemita, Kodiak Island, Shelikof Strait, Uyak Bay, Heard of Larson’s Inlet, Alaska (paralectotype, United States National Museum E2288) E basket F irregular plate with tubercles rising above G, H E. fraudatrix, Peter the Great Bay, Vostok Bay, Russia G plate with oval disk with four holes and a handle-like arch between the two holes in the longitudinal axis (underdeveloped table with modified 2-pillared spire?) H plate with small elevation in the center. Scale bars: 10 µm (A, B, E, G); 30 µm (F, H); 100 µm (C, D).