Noah's Keyhole Limpet
NameNoah's Keyhole Limpet
Scientific NameDiodora noachina
Common NameNoah's Keyhole Limpet
FamilyFissurellidae
GenusDiodora
Speciesnoachina
Geographic DistributionNorth Atlantic Ocean, including European coasts (e.g., British Isles, Norway, Mediterranean Sea) and occasionally reported from the western Atlantic.
Habitatintertidal
Shell Shapeconical
Average Size (mm)15-30
Identifying FeaturesThe most prominent identifying feature is the oval apical foramen (keyhole). The shell also exhibits strong, often nodulose, radial ribs and concentric growth lines, giving the margin a crenulated appearance.
Raritycommon
Author CitationLinnaeus, 1758
Description
A small, cap-shaped marine gastropod, commonly known as Noah's Keyhole Limpet. Its shell is characterized by a conical profile, strong radial ribs, and concentric growth lines, culminating in a distinctive oval apical opening or 'keyhole'. The shell color typically ranges from light to dark brown, often with radiating or concentric patterns. It lives attached to hard substrates in marine environments.
