21. ""'Calliostoma amamiense " "'is a species of sea snail, a marine gastropod mollusk in the family Calliostomatidae. 22. ""'Calliostoma angolense " "'is a species of sea snail, a marine gastropod mollusk in the family Calliostomatidae. 23. ""'Calliostoma antipodense " "'is a species of sea snail, a marine gastropod mollusk in the family Calliostomatidae. 24. ""'Calliostoma aporia " "'is a species of sea snail, a marine gastropod mollusk in the family Calliostomatidae. 25. ""'Calliostoma aprosceptum " "'is a species of sea snail, a marine gastropod mollusk in the family Calliostomatidae. 26. ""'Calliostoma arx " "'is a species of sea snail, a marine gastropod mollusk in the family Calliostomatidae. 27. ""'Calliostoma aupourianum " "'is a species of sea snail, a marine gastropod mollusk in the family Calliostomatidae. 28. ""'Calliostoma babelicum " "'is a species of sea snail, a marine gastropod mollusk in the family Calliostomatidae. 29. ""'Calliostoma barbouri " "'is a species of sea snail, a marine gastropod mollusk in the family Calliostomatidae. 30. ""'Calliostoma belauense " "'is a species of sea snail, a marine gastropod mollusk in the family Calliostomatidae.
