Tintinnid cysts

Distinctive flask-shaped cysts have been observed within the loricae of the tintinnids Favella serrata (Mobius),Helicostomella subulata (Ehrenberg), Parundella caudata (Ostenfeld) and Leprotintinnus pellucidus (Cleve) from samples taken by the Continuous Plankton Recorder. Similar cysts occur as a common element in palynological preparations of intertidal sediments from the British Isles. Encystment in tintinnids is now known for over 20 species and appears to be a more important process in the tintinnid life-cycle than previously believed. A possible relationship between tintinnid cysts and the extinct microfossil order Chitinozoa is proposed.