It is also possible that the specimen is a fossil, in which case additional large species must be considered.  Epitoniids have calcite shells, so they may look nice even though most associated shells are just holes in the rock.  Jung, 1971, reports a new fossil Sthenorhytis from Carriacou, though smaller than the modern pernobilis.

    Dr. David Campbell
    "Old Seashells"
    Biology Department
    Saint Mary's College of Maryland
    18952 E. Fisher Road
    St. Mary's City, MD  20686-3001 USA
    [log in to unmask], 301 862-0372 Fax: 301 862-0996
"Mollusks murmured 'Morning!'.  And salmon chanted 'Evening!'."-Frank Muir, Oh My Word!