endopolygeny

Endopolygeny is a form of asexual reproduction observed in some unicellular parasites within the phylum Apicomplexa. In endopolygeny, multiple rounds of mitotic nuclear division occur within a single, undivided cytoplasm, resulting in a large number of nuclei without immediate cytokinesis. After the nuclei reach the desired number, the cytoplasm undergoes internal budding to form many daughter cells within the same parent cell. The mature progeny are then released when the host cell ruptures or through further developmental steps.

This mode of division is a type of merogony and is related to other intracellular budding strategies such as endodyogeny and schizogony, but it is distinguished by the pattern and timing of nuclear multiplication and cytoplasmic division. In endopolygeny, the internal production of multiple daughters occurs within a single cell, producing a substantial brood of offspring before any exterior segmentation or release.

Endopolygeny has been described in several genera of Apicomplexa, including Besnoitia and Sarcocystis, among others, where it can maximize parasite yield within a host cell. The process contributes to rapid amplification during certain life-cycle stages and can influence the pathogenicity and transmission dynamics of the parasites.