Chitonidae – Chitoninae: Chiton (Rhyssoplax) tricostalis Pilsbry, 1894 (‘three-ribbed chiton’)
Synonym(s): tricostalis Pilsbry, 1894 aureomaculatus Bednall & Matthews, 1906.
Typical shell-length 28 mm. Lives intertidally and subtidally under rocks and stones, especially those near sand on moderately exposed shores. Native. Endemic to southeastern and southwestern Australia (TAS, VIC, SA and WA).