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Sverdrupiella usitata
Sverdrupiella usitata Bujak and Fisher, 1976
Holotype:Bujak and Fisher 1976, pl.2, fig.1-2; text-fig.2H
Locus typicus: Drake Point F-16, core 3722", Queen Elizabeth Islands, arctic Canada
Stratum typicum: ?Carnian-Norian
Original diagnosis: Bujak and Fisher, 1976, p.49
Cavate cysts, capsule oval to circular in polar view and occasionally absent. Capsule, when developed, often differing in size in individual specimens. Periphragm broader than long, typically seen in polar view and usually forming one rounded apical horn and one rounded antapical horn, both strongly reduced when present. Presence of second, strongly reduced antapical horn sometimes also suggested by swelling of periphragm. Cingulum rigid, defined along each margin by crest which typically bears acuminate, baculate, or clavate spines, or is rarely, distally smooth, undulate, or verrucose. Sulcus not defined on epitract, but delimited on hypotract by two distally smooth or undulate crests, or by two rows of spines sometimes proximally united. Remainder of periphragm usually bears randomly arranged baculate to clavate spines and occasional tubules or acuminate spines, but may be rarely smooth, granular, or verrucose. Archeopyle formed by displacement of one to three anterior intercalary plates offset with respect to middorsal line. Opening in capsule comprising simple split.
Dimensions: Holotype, periphragm breadth 75 µm, periphragm thickness 77 µm, capsule breadth 37 µm, capsule thickness 42 µm. Observed range, periphragm length 51-66 µm, periphragm breadth 54-81 µm, periphragm thickness 56-87 µm, capsule length 32-56 µm, capsule breadth 35-66 µm, capsule thickness 40-66 µm.
Holotype:Bujak and Fisher 1976, pl.2, fig.1-2; text-fig.2H
Locus typicus: Drake Point F-16, core 3722", Queen Elizabeth Islands, arctic Canada
Stratum typicum: ?Carnian-Norian
Original diagnosis: Bujak and Fisher, 1976, p.49
Cavate cysts, capsule oval to circular in polar view and occasionally absent. Capsule, when developed, often differing in size in individual specimens. Periphragm broader than long, typically seen in polar view and usually forming one rounded apical horn and one rounded antapical horn, both strongly reduced when present. Presence of second, strongly reduced antapical horn sometimes also suggested by swelling of periphragm. Cingulum rigid, defined along each margin by crest which typically bears acuminate, baculate, or clavate spines, or is rarely, distally smooth, undulate, or verrucose. Sulcus not defined on epitract, but delimited on hypotract by two distally smooth or undulate crests, or by two rows of spines sometimes proximally united. Remainder of periphragm usually bears randomly arranged baculate to clavate spines and occasional tubules or acuminate spines, but may be rarely smooth, granular, or verrucose. Archeopyle formed by displacement of one to three anterior intercalary plates offset with respect to middorsal line. Opening in capsule comprising simple split.
Dimensions: Holotype, periphragm breadth 75 µm, periphragm thickness 77 µm, capsule breadth 37 µm, capsule thickness 42 µm. Observed range, periphragm length 51-66 µm, periphragm breadth 54-81 µm, periphragm thickness 56-87 µm, capsule length 32-56 µm, capsule breadth 35-66 µm, capsule thickness 40-66 µm.