C. mariei was a small land snail found on Mayotte, the oldest island in the Comoros, an archipelago located between the northern coast of Mozambique and Madagascar. In the 1880s, 90 species of land snails and slugs were discovered in Mayotte, of which 46 percent were endemic to the island. In line with habitat loss, many of these snails, like C. mariei, have suffered extinction or declines in their population. However, a study of Mayotte in 2001 and 2002 resulted in the discovery of 20 new species of land snail and concluded that 56 percent of its endemic species were doing surprisingly well and thriving in the island’s forests and in areas where humans have cultivated or settled.