Figure 1. A. Radula, overview with anatomical directions. B–G. Magnifications, displaying cracks and wear (highlighted by arrows), probably resulting from interaction with hard ingesta particles (stones, spicules, Foraminifera tests). Abbreviations: a, anterior (towards the degenerative zone); CU, cusp; DE, denticle; GR, groove; IL, inner lateral; l, lateral; m, medial; OL A, outer lateral A; OL B, outer lateral B; OL C, outer lateral C; OL D, outer lateral D; OL E, outer lateral E; p, posterior (towards the building zone). Scale bars: A, 200 µm; B, 80 µm; C, D, E, F, 20 µm; G, 8 µm.