This study re-examines the type series of the Early Cretaceous freshwater bivalve Unio valdensis Mantell, 1844, in relation to the assignment of the species to the genus Paraheudeana Starobogatov (1970), and the subgenus Pseudunio by Mongin (1961). For the first time, we recognise the type specimens as incomplete lacking critical posterior portions of the shell. We observe that the lectotype, superficially oval in outline, has a shallow, but distinct postero-ventral sinus, seemingly out-grown, the broken ventral margin not preserving actual shell shape or the commissure. Significantly, many other specimens confirm the presence of the postero-ventral sinus and elongate-oval outline. It is unclear why Starobogatov removed Margaritifera (Pseudunio) valdensis but maybe the perceived oval outline was sufficient for separation. Combined with diagnostic characters such as mantle pits, we retain the freshwater mussel Unio valdensis in the genus Margaritifera and refute the validity of the genus Paraheudeana Starobogatov (1970). Araujo et al. (2016) reviewing the phylogeny of the Margaritiferidae, concluded only the genus Margaritifera was valid, discounting Pseudunio as a valid genus or subgenus, placing further doubt upon the use of the then subgenus, conversely more recent studies have supported the genus Pseudunio promoting it to a genus.

这项研究重新审查了早白垩纪淡水双壳类双壳纲Unid valdensis Mantell（1844年）的类型系列，涉及该物种对Paraheudeana Starobogatov属（1970年）和Pseudunio属（Mongin）（1961年）的分配。首次，我们将类型标本识别为不完整，缺少关键的壳体后部。我们观察到，电选型的轮廓是表面呈椭圆形，具有浅但明显的后腹窦，看似长大，腹缘折断，不能保留实际的壳形或连合。值得注意的是，许多其他标本证实存在后腹窦和细长卵形轮廓。目前尚不清楚为什么Starobogatov去除了玛格丽特（Pseudunio）valdensis，但也许椭圆形轮廓足以分离。结合诊断特征（例如地幔坑），我们将淡水贻贝Unio valdensis保留在Margaritifera属中，并驳斥了Paraheudeana Starobogatov属（1970）的有效性。Araujo等。（2016）回顾了玛格丽特科的系统发育，得出结论认为只有玛格丽特科属有效，而将假单胞菌视为有效属或亚属，对当时的亚属的使用提出了进一步的质疑，相反，最近的研究支持假单胞菌属将其推广为一个属。