Fig. 3. Arthropod bioerosion trace fossil Amphifaoichnus isp. on bone fragments of the rhynchosaurid archosauromorph Hyperodapedon mariensis (Tupi Caldas, 1933) from Buriol Site, Brazil, Hyperodapedon AZ, Carnian. A. UFRGS-PV-1581-T #3; A1, close up showing Amphifaoichnus isp. (note the bone chips) associated to a perpendicular boring (dashed outline) and feeding traces of Osteocallis mandibulus Roberts et al., 2007 (arrow; see also Fig. 4A1); A2, axial view of µCT scan showing the internal morphology of the tube, meniscate structures and the perpendicular boring; A3, coronal view of µCT scan showing the trace (dotted surface) and the destruction of both cortical (black outline) and trabecular bone. B. UFRGS-PV-1581-T #4; B1, specimen arrow) showing the uneven distribution of bone chips in the filling; B2, specimen in transversal view showing the rounded morphology of the filling. C. UFRGS-PV-1581-T #10; C1, specimen in negative relief with a small portion of filling still preserved (arrow); C2, close up of filling; C3, specimen in transversal view showing the U-shape of the boring.