Scacchia plenilunium Melvill & Standen, 1907, [Basis of the current name] Range: 51.7°S to 51.7°S; 57.7°W Depth: 0 m Distribution: Falkland Islands References: Dell (1964) c; Smaldon et al. (1976) DdNSEW Comments: A freshwater species erroneously described as marine.