Semiorbis hemicyclus is most similar to S. eliasiae and these taxa could easily be confused as the size range and morphometrics are overlapping. In general, S. eliasiae is greater in width and has a lower stria density.
Semiorbis rotundus values are much more curved.
Semiorbis catillifera has an undulation on the dorsal side at the valve middle. Valves have less curvature.
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