They are called mystery snails due to their ability to seemingly disappear and reappear in the tank. Some aquarists have noted that mystery snails have a tendency to vanish without a trace for a few days. Later, they mysteriously come back as if they never went missing in the first place.
Aside from their Houdini-like disappearing ability, there is another reason why they’re called mystery snails: these gastropods reproduce very quickly. Female mystery snails can keep laying eggs even after being without a mate for months.
Mystery snail babies often go unnoticed, only becoming visible when they become fully developed juveniles. Therefore, a tank’s snail population can appear to double overnight.