Ivory barnacle

Balanus eburneus

Family Balanidae - barnacles (crustacea)

Shell conical, made of 6 triangular plates (parietes) fused together with walls (radii) between plates; plates set close together at the base, diverge at the top, walls between wider at the top; sometimes plates extend past the walls giving an undulating or toothed appearance to aperture; plates are whitish, smooth; aperture is diamond-shaped except one point is flat; internal opercular plates distinctly striated longitudinally; base plate is calcareous, usually stays on hard substrate when barnacle is removed; tergum spur fairly long with basal margin curved, angular.
Similar Species
The ivory barnacle can be distinguished from most common barnacles by the longitudinal striations on its scutum (can be seen with the naked eye in larger specimens, or with magnifying glass in smaller ones). Most other barnacles scuta have radial striations. The ivory barnacle also has a deeply concaved basal margin of the tergum. This barnacle gets larger than most other common barnacles.
Gulf nearshore and bay
Maximum Size
2.5 cm (1 in)
Other Common Names
Previous Scientific Names