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Ginginodinium evittii
Ginginodinium evittii Singh, 1983, p.135–136, pl.46, figs.7–10.
NOW Trithyrodinium singhii. Originally Ginginodinium evittii, subsequently (and now) Trithyrodinium singhii.
Holotype: Singh, 1983, pl.46, fig.7
Locus typicus: Upper Shaftesbury Formation of the Peace River area
Stratum typicum: Early Cenomanian
Original description: Singh, 1983, p. 135
Proximate, peridinioid, cornucavate cysts with one short apical and two short, unequal antapical horns; apical horn 3-7 µm long, 2-4 µm wide, and with a blunt tip; the longer antapical horn conical, pointed, 2-4 µm long, and situated on the left side; the right antapical horn vestigial, frequently not developed; endophragm and periphragm thin, closely appressed except at the base of the horns (cornucavate); periphragm densely spinulose; spinules about 0.5 µm long; paratabulation not clearly discernible; paracingulum slightly helicoidal, 4-6 µm wide, and delineated by low, parallel, transverse, equatorial ridges; ventral ends of the paracingulum offset by about one paracingular width; parasulcus poorly delimited by a shallow depression narrowing anteriorly on the ventral hypocyst; archeopyle intercalary, type 3I; operculum free, composed of three disassociated paraplates la, 2a, and 3a of the appressed layers of endophragm and periphragm.
Size range: Length of the pericyst 37(49)59 µm. Holotype 54 µm. Breadth of the pericyst 30(39)47 µm. Holotype 41 µm. Specimens measured 55.
NOW Trithyrodinium singhii. Originally Ginginodinium evittii, subsequently (and now) Trithyrodinium singhii.
Holotype: Singh, 1983, pl.46, fig.7
Locus typicus: Upper Shaftesbury Formation of the Peace River area
Stratum typicum: Early Cenomanian
Original description: Singh, 1983, p. 135
Proximate, peridinioid, cornucavate cysts with one short apical and two short, unequal antapical horns; apical horn 3-7 µm long, 2-4 µm wide, and with a blunt tip; the longer antapical horn conical, pointed, 2-4 µm long, and situated on the left side; the right antapical horn vestigial, frequently not developed; endophragm and periphragm thin, closely appressed except at the base of the horns (cornucavate); periphragm densely spinulose; spinules about 0.5 µm long; paratabulation not clearly discernible; paracingulum slightly helicoidal, 4-6 µm wide, and delineated by low, parallel, transverse, equatorial ridges; ventral ends of the paracingulum offset by about one paracingular width; parasulcus poorly delimited by a shallow depression narrowing anteriorly on the ventral hypocyst; archeopyle intercalary, type 3I; operculum free, composed of three disassociated paraplates la, 2a, and 3a of the appressed layers of endophragm and periphragm.
Size range: Length of the pericyst 37(49)59 µm. Holotype 54 µm. Breadth of the pericyst 30(39)47 µm. Holotype 41 µm. Specimens measured 55.