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Trinovantedinium capitatum
Trinovantedinium capitatum Reid, 1977
Taxonomic senior synonym: Lejeunia (now Trinovantedinium) applanata Bradford, 1977 (April), by implication in Matsuoka (1984b, p.6), who did not specify priority, and de Verteuil and Norris (1992, p.397–398,408).
Harland, 1981 and Lewis et al., 1984 considered this species to represent the encysted stage of Protoperidinium pentagonum (Gran, 1902) Balech, 1974.
Holotype: Reid, 1977, pl.1, figs.6-8
Locus typicus: Rosslare Point, Republic of Ireland
Stratum typicum: Holocene
Original diagnosis: Reid, 1977, p.437
Pentagonal cysts with an apical horn and two antapical lobes or horns separated by a shallow antapical sulcus. Compressed dorsoventrally. Surface ornamented by short capitate spines and by a short bifid thickening of the wall forming an apical boss. Archeopyle intercalary and hexagonal.
Original description: Reid, 1977, p.437-438
The test has a rounded diamond shape in lateral and polar view. Short sutural and intratabular spines with capitate tips ornament the surface of the wall which is single layered, colourless and hyaline. The epitract is straight or convex and the hypotract has almost straight sides tapering to two rounded antapical lobes separated by a shallow antapical depression. The girdle is narrow, circular without displacement, excavated and defined by rows of capitate spines. It is inclined at between 15% and 30% to the longitudinal axis. Smooth areas without processes are found in the midventral, ventral sulcal and dorsal postcingular zones. In a few specimens, two shallow depressions were seen in the ventral sulcus which may be the scars of the flagellar pores in the thecate stage. The archeopyle is hexagonal, subrectangular with an operculum which is covered in spines.
Size: Holotype: length 77 µm, breadth 64 µm. Range of 15 specimens: length 54-80 µm, breadth 54-80 µm, thickness 42 µm (one specimen), maximum height of processes 5-7 µm, width of cingulum 4-6 µm.
Taxonomic senior synonym: Lejeunia (now Trinovantedinium) applanata Bradford, 1977 (April), by implication in Matsuoka (1984b, p.6), who did not specify priority, and de Verteuil and Norris (1992, p.397–398,408).
Harland, 1981 and Lewis et al., 1984 considered this species to represent the encysted stage of Protoperidinium pentagonum (Gran, 1902) Balech, 1974.
Holotype: Reid, 1977, pl.1, figs.6-8
Locus typicus: Rosslare Point, Republic of Ireland
Stratum typicum: Holocene
Original diagnosis: Reid, 1977, p.437
Pentagonal cysts with an apical horn and two antapical lobes or horns separated by a shallow antapical sulcus. Compressed dorsoventrally. Surface ornamented by short capitate spines and by a short bifid thickening of the wall forming an apical boss. Archeopyle intercalary and hexagonal.
Original description: Reid, 1977, p.437-438
The test has a rounded diamond shape in lateral and polar view. Short sutural and intratabular spines with capitate tips ornament the surface of the wall which is single layered, colourless and hyaline. The epitract is straight or convex and the hypotract has almost straight sides tapering to two rounded antapical lobes separated by a shallow antapical depression. The girdle is narrow, circular without displacement, excavated and defined by rows of capitate spines. It is inclined at between 15% and 30% to the longitudinal axis. Smooth areas without processes are found in the midventral, ventral sulcal and dorsal postcingular zones. In a few specimens, two shallow depressions were seen in the ventral sulcus which may be the scars of the flagellar pores in the thecate stage. The archeopyle is hexagonal, subrectangular with an operculum which is covered in spines.
Size: Holotype: length 77 µm, breadth 64 µm. Range of 15 specimens: length 54-80 µm, breadth 54-80 µm, thickness 42 µm (one specimen), maximum height of processes 5-7 µm, width of cingulum 4-6 µm.