The freshwater gastropod fauna of the Nanning
Basin in Guangxi Province exhibits certain similarities
to contemporaneous faunas at the family and genus
level, but differs from them by a remarkably high
diversity and extraordinary preservation. More than
eighty years ago, Odhner (1930) was the first scholar
who described freshwater molluscs from the Oligocene
deposits of Nanning. Based on shells collected
by W.J. Ding, Odhner (1930) detailed 20 species of
freshwater molluscs, of which he regarded 18 species
as new to science. His material yielded fragments of a
single large viviparid species, which he described as
Tulotoma gigas Odhner, 1930. A few years later, three
additional gastropod species, including the small viviparid
Viviparus wongi Yen, 1936, were described by
Yen (1936). Since then, the mollusc fauna of the Nanning
Basin fell into oblivion.