Coenocita

Coenocita, also called coenocyte in English, is a multinucleate cell that contains many nuclei within a shared cytoplasm. This condition arises when nuclear divisions occur without accompanying cytokinesis, or when two or more cells fuse to form a single cytoplasmic mass with multiple nuclei.

Coenocytic tissues occur in several groups. In fungi, many hyphae are coenocytic, lacking septa along much of their length and enabling rapid cytoplasmic transport. In certain green algae, such as Caulerpa and Valonia, the thallus is coenocytic, consisting of a single cytoplasmic network with numerous nuclei. Plasmodia of plasmodial slime molds are multinucleate coenocytic masses that function as a feeding stage and migrate through substrates.

In animals, true coenocytic cells are uncommon; multinucleated tissues such as skeletal muscle fibers and osteoclasts arise by cell fusion to form syncytia rather than by mitosis without cytokinesis. These examples illustrate the distinction between coenocytic organization and other forms of multinucleation produced by cell fusion.

Key features of coenocita include the absence or sparse occurrence of internal cross-walls (septa) and cytoplasmic streaming that distributes organelles and nutrients across large cellular extents. Nuclei may be evenly spaced or clustered, and the extent of cytoplasmic connectivity influences growth and metabolism in the organism.

Etymology traces to Greek koinos “common” and kytos “hollow vessel.” The English term coenocyte derives from the same roots, and coenocita is used in some languages as a direct equivalent.