Pedunculate, goose or goose-neck barnacles have a flexible, muscular stalk, known as the peduncle, which supports the main body known as the capitulum. Scalpellum scalpellum is typically whitish grey and grows up to 3 cm in height. The stalk is armoured with embedded calcareous scales. The capitulum is comprised of 13 distinct plates and a rudimentary rostrum, but is often covered by an epidermis with small articulated spines which can obscure these details. Scalpellum scalpellum is an androdioecious species, that is that there are hermaphrodites and males present. For Scalpellum scalpellum the typical individual is hermaphroditic and the dwarf complemental males can be found attached to the inside of the capitulum.