New collection work in Mount Flora, Hope Bay, Antarctic Peninsula, has confirmed the presence of bivalve moulds in the Jurassic Mount Flora Formation. In contrast to a twenty-first century article claiming to report the first discovery of fossil freshwater molluscs in Antarctica, evidence of these molluscs was first reported for Antarctica more than 110 years ago by J. Gunnar Andersson. The bivalve was formally described and named some 50 years later, by Camacho, as Antediplodon esperanzaensis. The species was subsequently transferred to the genus Diplodon for unknown reasons. Here, we illustrate specimens from the same locality for the first time with photographs, considering them Unionida incertae saedis, in view of the absence of diagnostic characters. In fact, two morphotypes are present, one elongated, very similar to the nominal species A. esperanzaensis, and another one subelliptical in shape.

中文翻译：

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（真正）第一个来自南极的化石淡水软体动物

在南极半岛希望湾的弗洛拉山新的采集工作已经证实，侏罗纪的弗洛拉山地层中存在双壳类霉菌。与二十一世纪的一篇报道声称在南极首次发现化石淡水软体动物的文章形成鲜明对比的是，J。Gunnar Andersson于110多年前首次在南极报道了这些软体动物的证据。大约50年后，卡马乔（Camacho）对这种双壳类进行了正式描述并命名为esperanzaensis。该物种随后被转移到Diplodon属中原因不明。在这里，由于缺乏诊断特征，我们首次使用照片对来自同一地区的标本进行了说明，并考虑到它们为无翅小Union。实际上，存在两种形态型，一种是细长的，非常类似于名义物种A. esperanzaensis，另一种是亚椭圆形。