Divisional morphogenesis in the marine ciliate Anteholosticha manca (Kahl, 1932) Berger, 2003 (Ciliophora: Urostylida)

The cortical development and macronuclear evolution of the marine hypotrichous ciliate Anteholosticha manca, collected from the coastal waters near Qingdao, China, were investigated using the protargol impregnation method.The morphogenesis of A.manca is generally typical for the genus, and can be characterized as the following features:(1) in the proter, a new oral primordium is formed on the bottom (beneath the pellicle) of the buccal cavity, disorganization of the parental undulating membranes do not contribute to the formation of this primordium; (2) FVT-cirral anlagen in both dividers develop independently, and very likely only a few midventral cirri join in the formation of these primordia; (3) both marginal row and dorsal kinety anlagen develop intrakinetally within the parental structure; (4) at the middle stage, macronuclear segments fuse together to form a single mass as observed in most of its related forms.