FIGURE 13A–B, Callochiton sp., S. Nilandu Atoll, Maldive, NHM 1903.4.11.71 (living specimen collected by J.S. Gardiner), close-up of the head and tail valves. C–H, Lucilina carnosa (Kaas, 1979), valves, Maldive. C–D, head valves, M13, showing differences in the number of ocelli rows, widths 3 and 3.1 mm, respectively. E, intermediate valve, M13, width 3.5 mm. F, tail valve, M13, width 3.3 mm. G–H, anomalous tail valve, dorsal and posterior views, respectively, M20, width 3.2 mm. I–K, Lucilina sp., valves, Maldive. I, head valve, M13, width 3.1 mm. J, intermediate valve, M20, width 4.7 mm. K, tail valve, M65, width 3.4 mm. L–M, Craspedochiton cf. laqueatus (Sowerby, 1842), head and intermediate valves, Maldive, M65, widths 5.7 and 5.2 mm, respectively. N, Craspedochiton sp., tail valve, Maldive, M65, width 5.8 mm. O–R, Cryptoplax burrowi E.A. Smith, 1884, NHM 1881.11.1.100, syntype, detached valves, coll. Coppinger, Port Molle, Queensland. O–P, intermediate valve, length 4 mm, dorsal and right lateral views, respectively. Q, intermediate valve, length 4.2 mm. R, head valve, length 3.5 mm.