Puu Kala Pt., Hawaii, 50 feet, 23mm

Kahe Pt., Oahu, 35 feet, 20mm

Uncommon at scuba depths.  Matte brown with strong curved ribs, subsutural band of deep punctures, fine spiral threads between ribs.  Attains 1 inch.   South Africa to Hawaii and French Polynesia.  Formerly known as Hastula swainsonii.