Two Types of Freshwater Snail Semisulcospira reiniana (Brot) (Mesogastropoda: Pleuroceridae) Identified by Electrophoresis

Abstract

The genetic and morphological variations of a freshwater snail, Semisulcospira reiniana were studied in the Lake Biwa water system and its adjacent two localities. The two types distinguished genetically were distributed sympatrically at Hamaotsu, Uji, and Mino-tsuya. MPI-A type snails had relatively small, and smooth or ribbed embryonic shells. MPI-B type snails had large and ribbed embryonic shells. However, these two types in the same locality could not be distinguished by adult shell morphology. Thus, the convergence of shell morphology with growth was suggested. These results clarified the confusion between these two types in past taxonomic studies of S. reiniana. © 1993, The Japanese Society of Limnology. All rights reserved.