Description
A sessile species, pedunculate in appearance. Size about 2 inches in length. Shell rudimentary, star-shaped, about a quarter of an inch in diameter, almost completely embedded in skin of the whale. Mantle extended to cover whole of body, and forming what appears to be a peduncle. Pseudo-peduncle cylindrical, flexible, narrowest at base, and with reflexed hood at the outer end surrounding the opening through which the cirri are protruded. Opercular valves absent.
Colour
Colour of shell, white; pseudo-peduncle, brown or dark chocolate-red; hood, light brown.
Distribution
World-wide but not common on the sei whale Balaenoptera borealis Lesson), the common finback Balaenoptera physalus (Linnaeus) ), and the blackfish, or pilot whale Globicephala ventricosa (Lacepède) ).
Notes
In spite of its pedunculate appearance, Xenobalanus globicipitis is an acorn barnacle in which the body has been elongated to form a false peduncle. Groups consisting of several individuals have been found attached to the tips of the flippers of the sei whale, an unusual habitat for any barnacle (Cachalot Whaling Station, 1925), and once it was found attached to the side of the head of a blue whale (Gordon C. Pike). Star-shaped scars on the skin of the whale mark old points of attachment.
