Truncatellas are small marine snails that spend most of their lives away from seawater, living among dead leaves, above the high tide line in mangrove areas. Last week I presented the Beautiful Truncatella, Truncatella pulchella Pfeiffer, 1839. The other, closely related species, is the Caribbean Truncatella, Truncatella caribaeensis Reeve, 1842. The latter has similar color, a variable sculpture pattern of 16–40 ribs. The Caribbean Truncatella is larger, reaching 8 mm (0.32 inch), and has a thinner outer lip, never “doubled,” as in the Beautiful Truncatella. [This is the 300th “Shell of the Week” column, all originally published by me on Sanibel’s Island Sun weekly newspaper.]