Crossopus fodiens, the water shrew, has also brown-stained teeth.
It is these differences in the teeth that has led to the water shrew being placed in a separate genus.
This indicates that the ancestors of the modern S. cinereus and of the water shrew had diverged from one another before that time.
The water shrew is much more local in its occurrence than are the other Shrews.
The water shrew is somewhat larger than the common shrew attaining to a length of five and a half inches including the tail.