Cross-sectional slices of the left first costal plate obtained through CT scanning of the carapace of the holotype of Eochelone brabantica (specimen IRSNB R 0001) from the Lutetian (middle Eocene) of the Saint-Remy-Geest locality (Walloon Brabant, Belgium). a–c. 3D models of the ventral (a, b) and lateral (c) views digitized by photogrammetry. a1–a8. Perpendicular view of the hole along the XY plane; b1–b8. Perpendicular view of the hole along the YZ plane; c1–c4. Parallel view of the hole along the XZ plane. Scale bars: 2 cm. The arrow indicates the hypodense bone structure.