Cuba is home to the world’s greatest diversity of snails, but no others have shells with such a range of colors and complex patterns. Painted snails, in the genus Polymita, have long been sought by collectors, who sell the shells to tourists or trade them abroad to the United States and Europe. This demand is one reason why Cuba lists all six species as critically endangered, and why it’s been illegal for more than a decade to take these snails from the wild. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which regulates global commerce in wildlife, has banned their trade since 2017.