Plate P2. The modified Kofoid system (as outlined in Fensome et al., 1993b) is used in the labeling of individual plates for the gonyaulacaleans. The Kofoid system is used in the labeling of plates in the peridinialeans. The archeopyle location is denoted by diagonal lines. 1. Ataxiodinium choane Reid 1974. Dorsal view. Holotype dimensions: overall diameter = 49 µm, endocyst diameter = 30 µm. 2. Barssidinium evangelineae Lentin et al. 1994. Dorsal view. Holotype dimensions: cyst length = 99 µm, cyst width = 99 µm, process length up to 11 µm. 3. Biconidinium longissimum Islam 1983c. Ventral view. Holotype dimensions: pericyst length = 140 µm, pericyst width = 51 µm, endocyst length = 57 µm, endocyst width = 49 µm. 4. Cannosphaeropsis passio de Verteuil and Norris 1996a. Dorsal view. Holotype dimensions: overall length = 120 µm, overall width = 100 µm. 5, 6. Callaiosphaeridium asymmetricum (Deflandre and Courteville 1939) Davey and Williams 1966b. Holotype dimensions: central body diameter = 40 µm, process length = 22–34 µm; (5) oblique apical view; (6) antapical view. 7. Cannosphaeropsis utinensis O. Wetzel 1933b. Holotype dimensions: overall length = 116 µm, overall width = 88 µm, central body length = 44 µm, central body width = 36 µm. 8. Carpodinium obliquicostatum Cookson and Hughes 1964. Ventral view. Holotype dimensions: length = 73 µm, width = 36 µm. 9, 10. Carpatella cornuta Grigorovich 1969a. Holotype dimensions: length = 114 µm, width = 90 µm; (9) ventral view; (10) dorsal view. 11. Cassiculosphaeridia reticulata Davey 1969a. Oblique ventral view. Holotype dimensions: diameter = 38 µm x 38 µm, crest height = 4–6 µm. 12. Cerebrocysta bartonensis Bujak in Bujak et al. 1980. Dorsal view. Range of type material: overall diameter = 24 µm x 28 µm, crest height up to 2 µm. 13. Cerebrocysta poulsenii de Verteuil and Norris 1996a. Right lateral view. Holotype dimensions: length = 37 µm, width = 27 µm. 14. Cerodinium diebelii (Alberti 1959b) Lentin and Williams 1987. Dorsal view. Holotype dimensions: pericyst length = 180 µm, pericyst width = 44 µm. 15. Cerodinium wardenense (Williams and Downie 1966c) Lentin and Williams 1987. Dorsal view. Holotype dimensions: pericyst length = 57 µm, pericyst width = 46 µm, endocyst length = 36 µm, endocyst width = 43 µm. 16. Charlesdowniea crassiramosa (Williams and Downie 1966b) Lentin and Vozzhennikova 1989. Dorsal view. Holotype dimensions: pericyst length = 125 µm, pericyst width = 122 µm, endocyst length = 80 µm, endocyst width = 71 µm. 17, 18. Charlesdowniea columna (Michoux 1988) Lentin and Vozzhennikova 1990. Holotype dimensions: pericyst = 121 µm x 124 µm, archeopyle length = 21 µm, archeopyle width = 27 µm; (17) ventral view; (18) dorsal view. 19. Charlesdowniea edwardsii (Wilson 1967c) Lentin and Vozzhennikova 1989. Dorsal view. Holotype dimensions: pericyst length = 96 µm, pericyst width = 107 µm, endocyst length = 50 µm, endocyst width = 58 µm, apical horn length = 16 µm, antiapical horn length = 19 µm, lateral horns length = 19 µm. 20. Chatangiella verrucosa (Manum 1963) Lentin and Williams 1976. Dorsal view. Holotype dimensions: pericyst length = 134 µm, pericyst width = 83 µm.

Plate P2. The modified Kofoid system (as outlined in Fensome et al., 1993b) is used in the labeling of individual plates for the gonyaulacaleans. The Kofoid system is used in the labeling of plates in the peridinialeans. The archeopyle location is denoted by diagonal lines. 1. Ataxiodinium choane Reid 1974. Dorsal view. Holotype dimensions: overall diameter = 49 µm, endocyst diameter = 30 µm. 2. Barssidinium evangelineae Lentin et al. 1994. Dorsal view. Holotype dimensions: cyst length = 99 µm, cyst width = 99 µm, process length up to 11 µm. 3. Biconidinium longissimum Islam 1983c. Ventral view. Holotype dimensions: pericyst length = 140 µm, pericyst width = 51 µm, endocyst length = 57 µm, endocyst width = 49 µm. 4. Cannosphaeropsis passio de Verteuil and Norris 1996a. Dorsal view. Holotype dimensions: overall length = 120 µm, overall width = 100 µm. 5, 6. Callaiosphaeridium asymmetricum (Deflandre and Courteville 1939) Davey and Williams 1966b. Holotype dimensions: central body diameter = 40 µm, process length = 22–34 µm; (5) oblique apical view; (6) antapical view. 7. Cannosphaeropsis utinensis O. Wetzel 1933b. Holotype dimensions: overall length = 116 µm, overall width = 88 µm, central body length = 44 µm, central body width = 36 µm. 8. Carpodinium obliquicostatum Cookson and Hughes 1964. Ventral view. Holotype dimensions: length = 73 µm, width = 36 µm. 9, 10. Carpatella cornuta Grigorovich 1969a. Holotype dimensions: length = 114 µm, width = 90 µm; (9) ventral view; (10) dorsal view. 11. Cassiculosphaeridia reticulata Davey 1969a. Oblique ventral view. Holotype dimensions: diameter = 38 µm x 38 µm, crest height = 4–6 µm. 12. Cerebrocysta bartonensis Bujak in Bujak et al. 1980. Dorsal view. Range of type material: overall diameter = 24 µm x 28 µm, crest height up to 2 µm. 13. Cerebrocysta poulsenii de Verteuil and Norris 1996a. Right lateral view. Holotype dimensions: length = 37 µm, width = 27 µm. 14. Cerodinium diebelii (Alberti 1959b) Lentin and Williams 1987. Dorsal view. Holotype dimensions: pericyst length = 180 µm, pericyst width = 44 µm. 15. Cerodinium wardenense (Williams and Downie 1966c) Lentin and Williams 1987. Dorsal view. Holotype dimensions: pericyst length = 57 µm, pericyst width = 46 µm, endocyst length = 36 µm, endocyst width = 43 µm. 16. Charlesdowniea crassiramosa (Williams and Downie 1966b) Lentin and Vozzhennikova 1989. Dorsal view. Holotype dimensions: pericyst length = 125 µm, pericyst width = 122 µm, endocyst length = 80 µm, endocyst width = 71 µm. 17, 18. Charlesdowniea columna (Michoux 1988) Lentin and Vozzhennikova 1990. Holotype dimensions: pericyst = 121 µm x 124 µm, archeopyle length = 21 µm, archeopyle width = 27 µm; (17) ventral view; (18) dorsal view. 19. Charlesdowniea edwardsii (Wilson 1967c) Lentin and Vozzhennikova 1989. Dorsal view. Holotype dimensions: pericyst length = 96 µm, pericyst width = 107 µm, endocyst length = 50 µm, endocyst width = 58 µm, apical horn length = 16 µm, antiapical horn length = 19 µm, lateral horns length = 19 µm. 20. Chatangiella verrucosa (Manum 1963) Lentin and Williams 1976. Dorsal view. Holotype dimensions: pericyst length = 134 µm, pericyst width = 83 µm.