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Heibergella aculeata
Heibergella aculeata Bujak and Fisher, 1976
Holotype: Bujak and Fisher, 1976, pl.8, figs.14-16
Locus typicus: Skybattle Bay C-15, cuttings 8110-8170" Queen Elizabeth Islands, arctic Canada
Stratum typicum: Carnian-Norian
Original diagnosis: Bujak and Fisher, 1976, p.56
Apparently single-walled cysts. Epitract of triangular to subtriangular outline. Hypotract of ovoidal or symmetrical or asymmetrical trapezoidal outline. Small, distinct apical horn always present, and presence of one or two antapical horns sometimes suggested by small lobes or relatively long spines. Cingulum circular or slightly laevo-rotary, delimited by two rows of proximally united spines. Sulcal position marked by depression near cingulum on hypotract and sometimes on epitract. Sulcus also occasionally bordered by two rows of spines. Remainder of wall bearing dense cover of spines similar to those of cingular borders, these being evexate, bifid, bifurcate, or rarely acuminate or baculate, and either isolated or proximally united by low crests in fielded arrangement. Arrangement possibly of peritabular significance on occasional specimens. Archeopyle anterior intercalary, formed by loss of two or sometimes three plates.
Dimensions: Holotype, length 69 Ám, breadth 45 Ám. Observed range, length 48-72 Ám, breadth 43-51 Ám.
Holotype: Bujak and Fisher, 1976, pl.8, figs.14-16
Locus typicus: Skybattle Bay C-15, cuttings 8110-8170" Queen Elizabeth Islands, arctic Canada
Stratum typicum: Carnian-Norian
Original diagnosis: Bujak and Fisher, 1976, p.56
Apparently single-walled cysts. Epitract of triangular to subtriangular outline. Hypotract of ovoidal or symmetrical or asymmetrical trapezoidal outline. Small, distinct apical horn always present, and presence of one or two antapical horns sometimes suggested by small lobes or relatively long spines. Cingulum circular or slightly laevo-rotary, delimited by two rows of proximally united spines. Sulcal position marked by depression near cingulum on hypotract and sometimes on epitract. Sulcus also occasionally bordered by two rows of spines. Remainder of wall bearing dense cover of spines similar to those of cingular borders, these being evexate, bifid, bifurcate, or rarely acuminate or baculate, and either isolated or proximally united by low crests in fielded arrangement. Arrangement possibly of peritabular significance on occasional specimens. Archeopyle anterior intercalary, formed by loss of two or sometimes three plates.
Dimensions: Holotype, length 69 Ám, breadth 45 Ám. Observed range, length 48-72 Ám, breadth 43-51 Ám.