One of the most common ones we find in the backwaters and placid shores of the Upper Mississippi. Spiral and black. Seems to grow to one half inch. Soft shelled and seemingly not invasive. It is very mobile and aggressive. Will attack other species of freshwater snails many times larger than its size like a pack of hyenas, from an unfortunate aquarium experiment. I realize there are over 50 of aquatic snails in NE Iowa, but perhaps the commonness

of this one might help with identification.

Thanks for looking at this.