Ivory Barnacle
Amphibalanus eburneus
Summary 2
Amphibalanus eburneus, the ivory barnacle, is a species of acorn barnacle in the family Balanidae. It occurs on the east coast of North America, the Caribbean Sea and Gulf of Mexico.
Description 3
The ivory barnacle, Balanus eburneus, is a medium-sized sessile barnacle belonging to the class Cirripedia. This group contains approximately 900 described species, about two-thirds of which are free-living barnacles that foul or attach to rocks and other hard intertidal and submerged surfaces (Ruppert & Barnes 1994). Like other members of the suborder Balanomorpha, the soft tissue of B. eburneus is protected within a series of rigid plates, known as capitular plates. The solid white plates of the ivory barnacle form a conical appearance that is largest at the base, with a diamond-shaped opening guarded by a movable opercular lid composed of two symmetrical triangular halves (eg. Gosner 1978). Each of these halves contains two plates, the tergum and the scutum. During feeding, excretion, larval release and copulation, the operculum opens as the terga and scuta are flexed out to the sides.
Distribution 4
The ivory barnacle is considered one of the most common fouling organisms found in the India River Lagoon, Florida (Hoskin & Courtney 1983, Mook 1976). Single individuals to large aggregations can be found in all intertidal India River Lagoon habitats. Age, Size and Lifespan: The maximum age of B. eburneus is unknown, and the lifespan can vary with food availability and environmental factors. The maximum reported height and diameter for the ivory barnacle is about 2.5 cm (Gosner 1978, Kaplan 1988), though most specimens are much smaller.
Look alikes 5
Several species of acorn or balanoid barnacles inhabit the waters of Florida. 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).
Reproduction 6
Like most other free-living barnacles, B. eburneus is hermaphroditic. However, populations reproduce via cross-fertilization. The penis of B. eburneus is quite long, and can be protruded out of the body and into the mantle cavity of nearby individuals where sperm is deposited on the first cirri of the recipient before penetrating the ovisac and reaching the lamellae or egg mass (Ruppert & Barnes 1994). The eggs are brooded in the mantle cavity and released as swimming larvae once development is complete.
Link to Access Genomic Data 7
http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=637417&lvl=0
Sources and Credits
- (c) Ken-ichi Ueda, some rights reserved (CC BY), uploaded by Ken-ichi Ueda
- Adapted by matbio from a work by (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Amphibalanus_eburneus
- Adapted by matbio from a work by (c) Smithsonian Marine Station at Fort Pierce, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/11525672
- Adapted by matbio from a work by (c) Smithsonian Marine Station at Fort Pierce, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/11525673
- Adapted by matbio from a work by (c) Smithsonian Marine Station at Fort Pierce, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/11525675
- (c) Smithsonian Marine Station at Fort Pierce, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/11525677
- (c) Emily Rose Sharkey, all rights reserved
