Several species of acorn or balanoid barnacles inhabit the waters in and around the IRL. Probably the most commonly confused species with B. eburneus is the white bay barnacle, Balanus improvisus. This species is usually smaller than B. eburneus, at a maximum height of about 0.6 cm (Kaplan 1988). Definitive identification between species of acorn barnacles similar in appearance usually requires examination of the shape of the terga and scuta through dissection. The striped acorn barnacle, Balanus amphitrite, is similar in size and shape, but bears pink vertical stripes on the capitular plates. The non-native titan acorn barnacle, Megabalanus coccopoma, recently discovered in Florida waters as of the date of this text, has plates that are distinctly pink in color. The average size of most M. coccopoma is considerably larger than the other acorn barnacles found in Florida.Regional Occurrence & Habitat Preference: The range of the ivory barnacle is extensive, probably due in part to introductions of the species via the ballast water and hull fouling of ships (eg. Hawaii, Matsui et al. 1964). The native distribution of B. eburneus extends from Nova Scotia to Florida, the Caribbean and Gulf of Mexico (Kaplan 1988). Large aggregations of the barnacle can be found on a variety of hard surfaces at or below the low tide line to a depth of about 37 m (Voss 1980), including: rocks; oysters, mussels and other mollusk shells; pilings; buoys; seawalls and prop roots of the red mangrove, Rhizophora mangle (Kaplan 1988, Ruppert & Fox 1988, Voss 1980, Zullo 1979).