A checklist of Australian marine Cenozoic Mollusca Author Darragh, Thomas A. text Memoirs of Museum Victoria 2024 2024-08-23 83 37 206 https://doi.org/10.24199/j.mmv.2024.83.02 journal article 10.24199/j.mmv.2024.83.02 1447-2554 Placamen placidum (Philippi, 1844) Placamen placidum (Philippi, 1844) .— Ludbrook, 1978: 78 , pl. 9, figs 5, 6. Distribution . Eucla Basin: Roe Calcarenite. Otway Basin: Whalers Bluff Formation. Bass Basin: Memana Formation. Southeastern Australia (living). Age : late Pliocene–present. Gomphina Mörch, 1853