Diagnosis_Species: Parasites of Thalassicolles. The trophont grows inside the endoplasm of the capsule, without dividing, and totally substitutes to the host endoplasm (including the host nucleus). Food uptake, by osmotrophy, using particular structures. The nucleus becomes geant (synenergide). Numerous trichocysts observed in the trophont. Sporogenesis occurs when the parasite occupy the whole central capsule. Sporocytes and spores have typical dinocaryon. The calymna of the Thalassicoles desintegrates, following by the central capsule, leading to the liberation of the spores. Free-living spores may survived several days, additional divisions have been observed. (Hollande and Corbel 1952).
Body_length: 600-950 µm