Sea acorn balianus is a genus of barnacle cancers (suborder of sea acorns). Adult individuals of this biological species lead an immobile life, attaching themselves to solid surfaces. Resettlement is possible only at the larval stage. Currently, about 60 species belong to this genus.
These marine animals (photo below) have a calcareous shell that attaches to the substrate. The sink itself consists of 6 plates, four of which form a lid and have the ability to move apart. The crustacean lies at the bottom of this house, protruding the limbs between the open plates. At the same time, he makes energetic rhythmic swings in order to drive water with food particles into the house.
In diameter, the sea acorn reaches seven centimeters, and in length - 13. Coloring, as a rule, whitish or grayish with longitudinal stripes of purple or brown.
The sea acorn, with its wide sole, attaches to any surface - mollusk shells, stones, tree roots, piles of piers, ship bottoms, and also to various animals. Below you can see photos of marine animals to which the acorn can attach. The sticky substance that is produced by the sea acorn is very stable. It withstands temperatures up to 200 degrees and is not affected by alkalis, acids and other solvents.
In turn, soft sponges often settle on large cusps of marine acorns, for which the crustacean house is a reliable and solid foundation.
Sea Life Acorn Life Cycle
The development of the sea acorn consists of the following phases: egg, larva, adult crustacean. The larvae that emerge from the eggs swim freely and go through two stages: nauplius and cipris. In cold-water species, the larval stage lasts from 2 weeks to the 1st month, and in tropical species it takes about 3-5 days.
Larvae in the cipris stage do not feed. For a while they swim, but, having found themselves in favorable conditions, they are attached to the substrate. Adult crustaceans lead a still life.
The sea acorn grows and develops quite rapidly. In the tropical zone, some species reach maturity within 1-2 weeks after settling. In the colder Baltic Sea, this takes about three months. The lifespan of crustaceans is from 1-2 years to 5-7 or more.
How the marine acorn breeds
Between individuals sitting nearby, cross-fertilization is carried out. The sea acorn is a hermaphrodite, that is, each of them has both male and female sex glands. Near the base of the anterior pair of legs, oviducts open, from which eggs emerge, which then enter the mantle cavity. The vas deferens flow into the tubular copulative male organ, which straightens when mated, protrudes outward and enters the mantle cavity of the anterior individual. The sperm secreted by him fertilizes eggs. Studies have been carried out, during which it became clear that the sea acorn can multiply alone. After fertilization, groups of eggs in the mantle cavity join into the ovum and begin crushing.
Cold-loving individuals form eggs in the summer, fertilize them in the winter so that the larvae emerge in the spring. Heat-loving individuals lay eggs several times throughout the year.
