The life history of Pyramimonas amylifera Conrad (Prasinophyceae)

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Several possible life history stages of a clone of Pyramimonas amylifera Conrad (Prasinophyceae) have been encountered in culture studies. These include: 1) octoflagellates; 2) cysts; 3) quadriflagellates; 4) biflagellates; and 5) multilobate cells with each lobe bearing eight flagella. The octoflagellates have the ultra-structural characteristics previously documented for P. amylifera. Scanning electron microscopy was used to examine surfaces of cysts and biflagellates. Scales of the type which form the middle (basket-shaped) and outer (coronate) scale layers on the octoflagellate were observed on the surface of cysts. Scales of the type which form the middle body layer on octoflagellates were observed on the bodies of biflagellates. Biflagellates, quadriflagellates, and empty cysts were observed in several cultures which had been subjected to a 5-week dark incubation before return to a low-light regime. In one of those cultures, a single cyst containing motile swarmers was observed. The biflagellates or quadriflagellates may represent cyst-germination products. © 1980 IRL Press Limited.

Publication Title, e.g., Journal

Journal of Plankton Research