Callianira cristata. A-B. Drawing from the original description (specimen length 12 mm) (modified from Moser 1909) from Gauss Station, Antarctica: lateral view of the substomodeal plane (A) and the subtentacular plane (B); C-H. Specimen MCMEC2019_Callianira_cristata_a observed on 22/11/2018: lateral-substomodeal views (C-D, G-H) oral view (E) and latero-aboral view (F). The contrast and brightness of images G-H were strongly modified to reveal underlying morphological structures. Abbreviations: ad-c., adradial canal; c.g., ciliary groove; m., mouth; o.t.s., opening of tentacle sheath; pe-c., perradial canal; r., ridge; st., statocyst; ss-cr., substomodeal comb row; st-cr., subtentacular comb row; t.b., tentacle bulb. C-H photos courtesy: E. Cimoli.