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Lejeunecysta oliva
Lejeunecysta oliva (Reid, 1977) Turon and Londeix, 1988
Originally Trinovantedinium, subsequently (and now) Lejeunecysta.
Taxonomic senior synonym: Lejeunia (now Lejeunecysta) paratenella, according to Harland (1977b, p.105) - however, Turon and Londeix (1988, p.344) retained Trinovantedinium (as Lejeunecysta) oliva.
Holotype: Reid, 1977, pl.1, figs.12-13
Locus typicus: Dover, England
Stratum typicum: Recent
Original diagnosis: Reid, 1977, p.440: Trinovantedinium olivum
Pentagonal cyst in dorsoventral view with two pointed, solid tipped antapical horns. Wall thin, surface smooth; thickened ridges marking a narrow excavated, circular cingulum. Archaeopyle intercalary elongated posterior/anteriorly.
Original description: Reid, 1977, p.440: Trinovantedinium olivum
The test is diamond shaped in lateral view and compressed dorsoventrally with an epitract and hypotract of equal size. Two pointed antapical horns with solid terminations are separated by a deep to shallow antapical depression. A prominent apical horn is flattened at its tip and marked by a thickening of the wall. The hypotract is concave and the epitract is straight to convex occasionally with a shoulder. The wall is single layered and an olive brown colour.
Thickened ridges define a narrow circular, excavated girdle at 90¦ to the longitudinal axis. Two small posterior sulcal thickenings of the wall are probably flagellar pore scars. Micro-verrucate ornament may connect these to the girdle. A similar thickening occurs in the apical region possibly reflecting the apical pore. Diverging thickenings of the wall may mark the margins of lhe sulcus in the epitraclal area. The ventral sulcus is wide and very deep in both the epitract and hypotract. A subrectangular intercalary archeopyle is elongated in a posterior/anterior direction with a length/breadth ratio of approximately 2:1. Four specimens of this species were found with an outer periphragm. The thin colourless periphragm adopted the shape of the inner cyst. The archeopyle operculum has broken away on one of the inner cysts but the method of opening in the periphragm was not seen.
Dimensions: Holotype Length 82 Ám Breadth 80 Ám Range: Length 63-83 Ám. Breadth 74-88 Ám Thickness 53 Ám (one specimen) Girdle width 5-6 Ám. Antapical tips 36-42 Ám apart. Number of specimens measured 15.
Originally Trinovantedinium, subsequently (and now) Lejeunecysta.
Taxonomic senior synonym: Lejeunia (now Lejeunecysta) paratenella, according to Harland (1977b, p.105) - however, Turon and Londeix (1988, p.344) retained Trinovantedinium (as Lejeunecysta) oliva.
Holotype: Reid, 1977, pl.1, figs.12-13
Locus typicus: Dover, England
Stratum typicum: Recent
Original diagnosis: Reid, 1977, p.440: Trinovantedinium olivum
Pentagonal cyst in dorsoventral view with two pointed, solid tipped antapical horns. Wall thin, surface smooth; thickened ridges marking a narrow excavated, circular cingulum. Archaeopyle intercalary elongated posterior/anteriorly.
Original description: Reid, 1977, p.440: Trinovantedinium olivum
The test is diamond shaped in lateral view and compressed dorsoventrally with an epitract and hypotract of equal size. Two pointed antapical horns with solid terminations are separated by a deep to shallow antapical depression. A prominent apical horn is flattened at its tip and marked by a thickening of the wall. The hypotract is concave and the epitract is straight to convex occasionally with a shoulder. The wall is single layered and an olive brown colour.
Thickened ridges define a narrow circular, excavated girdle at 90¦ to the longitudinal axis. Two small posterior sulcal thickenings of the wall are probably flagellar pore scars. Micro-verrucate ornament may connect these to the girdle. A similar thickening occurs in the apical region possibly reflecting the apical pore. Diverging thickenings of the wall may mark the margins of lhe sulcus in the epitraclal area. The ventral sulcus is wide and very deep in both the epitract and hypotract. A subrectangular intercalary archeopyle is elongated in a posterior/anterior direction with a length/breadth ratio of approximately 2:1. Four specimens of this species were found with an outer periphragm. The thin colourless periphragm adopted the shape of the inner cyst. The archeopyle operculum has broken away on one of the inner cysts but the method of opening in the periphragm was not seen.
Dimensions: Holotype Length 82 Ám Breadth 80 Ám Range: Length 63-83 Ám. Breadth 74-88 Ám Thickness 53 Ám (one specimen) Girdle width 5-6 Ám. Antapical tips 36-42 Ám apart. Number of specimens measured 15.