Calcitic resting cysts in Peridinium trochoideum (Stein) Lemmermann, an autotrophic marine dinoflagellate

摘要: Abstract Numerous calcareous cysts of the marine dinoflagellate Peridinium trochoideum (Stein) Lemmermann have been obtained from a fresh clonal culture that was isolated by incubation cyst sediment in Harrington Sound, Bermuda. Electron diffraction analysis demonstrates crystalline spines these are composed calcite. A few additional observations made concerning encystment-excystment behaviour, vegetative cell morphology, and biogeographic distribution P. trochoideum. The phylogenetic relationships between this species other living fossil spore-producing dinoflagellates also discussed briefly.