Williams et al. 1978 AASP Contrib 7

DINOFLAGELLATES: Unicellular aquatic organisms, motile and heterotrophic, parasitic, or photosynthetic. Generally with two flagella, one within an encircling sulcus, the second (longitudinal) oriented porteriorly. Life cycles various, but often with motile thecate stage having a cellulose cell wall, and a resting cyst (hypnozygote) with a chitinous or "dinosporinous" wall forming inside the theca. Form of the cyst ranges from similar to the theca (proximate) to bearing several trumpet-shaped processes (chorate). Theca and cyst often comprised of polygonal plates separated by sutures
Chorate cysts categorized based on relation of processes to theca sutures. Example: Spiniferate cysts have processes along the sutures. Cyst often with a polygonal opening (arceopyle) through which excystment occurs.

Evitt 1970 G&M

Evitt 1970 G&M

Andrew MacRea
Archeopyle (MacRea)

Owen Davis 12/99