Tutuila
... that 11 out of 19 species of land snails found on the Samoan island of Tutuila are endemic?
... that 11 out of 19 species of land <a href="./Snail" id="mwBNQ" rel="mw:WikiLink" title="Snail">snails</a> found on the <a href="./Samoan_Islands" id="mwBNU" rel="mw:WikiLink" title="Samoan Islands">Samoan</a> island of <b id="mwBNY"><a href="./Tutuila" id="mwBNc" rel="mw:WikiLink" title="Tutuila">Tutuila</a></b> are endemic?