Gran bellota de mar, Balanus de tres filos

Description:

Los cirrípedos (Cirripedia) son una infraclase de crustáceos maxilópodos denominados comúnmente percebes, incluyendo la bellota de mar y la anatifa. De forma similar a un volcán. Presentan seis placas laterales, levemente separadas en la parte superior. Cada placa es de color rosáceo, con varias crestas verticales. El par más largo cierra la abertura bucal. Alcanzan los 2 centímetros de ancho. Denominado trigonus por ser triangular la apertura superior de la concha. Bajo el agua, el animal abre el caparazón y saca de entre sus cubiertas dos apéndices ramificados que baten regularmente las aguas para captar alimento. Vive adherido a superficies de conchas. Es muy cosmopolita y se puede adherir a seres vivos, desde conchas a cetaceso e incluso los cascos de los barcos.

Habitat:

Sobre la cocha de un mejillón procedente de Galicia (España). En un domicilio particular.

Notes:

Balanus perforatus is a cirripedia with a base reaching 3 cm in diameter and up to 5 cm for deeper specimens. The external plates are vertically ribbed. Their pointed ends as well as the conical organization of the plates evoke the form of a small volcano. They are greyish with shades of purple or pink. The operculum that closes the upper aperture is depressed inside the cone formed by the plates. This operculum consists of two pairs of movable plates that open to allow the cirri out so that the barnacle could catch food. In case of emergency or during emersed periods, the operculum is kept hermetically closed thanks to a brown or purple flap with blue and white patches. The common barnacle generally lives in groups attached to rocks or immersed structures such as ships' bottom. It is found from surface to 20 meters deep in the Atlantic Ocean from West Africa to Wales, in the English Channel and in the Mediterranean Sea.