Cysts with antapical protusions

Zonneveld, K.A.F. and Pospelova V. (2015). A determination key for modern dinoflagellate cysts. Palynology 39 (3), 387- 407.

smooth wall
bifurcate and trifucrate processes
antapical processes connected with septa forming a crown-shape
Spiniferites mirabilis +

smooth wall
trifurcate processes
two antapical processes connected with an enlarged septum
Spiniferites membranaceus +

smooth wall

trifurcate processes

no apical boss

two antapical processes enlarged

Spiniferites pacificus