What is "statoblast"

Statoblast \Stat"o*blast\ (st[a^]t"[-o]*bl[a^]st), n. [Gr. stato`s standing (i. e., remaining) + -blast.] (Zo["o]l.) One of a peculiar kind of internal buds, or germs, produced in the interior of certain Bryozoa and sponges, especially in the fresh-water species; -- also called winter buds.

Note: They are protected by a firm covering, and are usually destined to perpetuate the species during the winter season. They burst open and develop in the spring. In some fresh-water sponges they serve to preserve the species during the dry season. See Illust. under Phylactol[ae]mata.

n. (context zoology English) One of a peculiar kind of internal buds, or germs, produced in the interior of certain Bryozoa and sponges. They are protected by a firm covering, and are usually destined to perpetuate the species during the winter season. They burst open and develop in the spring. In some freshwater sponges they serve to preserve the species during the dry season.

Statoblasts are a means to reproduce asexually by a method that is unique among bryozoans and enables a colony's lineage to survive the variable and uncertain conditions of freshwater environments. Statoblasts are masses of cells that function as "survival pods" rather like the gemmules of sponges. Statoblasts form on the funiculus (cord) connected to the parent's gut, which nourishes them. As they grow, statoblasts develop protective bivalve-like shells made of chitin. When they mature, some types stick to the parent colony, some fall to the bottom, some contain air spaces that enable them to float, and some remain in the parent's cystid (outer casing) to re-build the colony if it dies. Statoblasts can remain dormant for considerable periods, and while dormant can survive harsh conditions such as freezing and desiccation. They can be transported across long distances by animals, floating vegetation, currents and winds. When conditions improve, the valves of the shell separate and the cells inside develop into a zooid that tries to form a new colony. A study estimated that one group of colonies in a patch produced 800,000 statoblasts.