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Eurydinium ovatum
Eurydinium ovatum , Vieira, M. et al., 2018, p. 187
Holotype: Vieira, M. et al., 2018, Plate 3, figure 9
Type locality: southern part of the Ormen Lange field (Norway) over the Danian-aged reservoir
Local stratigraphical range: Danian (Early Paleocene)
Original description: Vieira, M. et al., 2018:
Diagnosis:
Pericyst circumcavate peridinoid to deflandreoid, being elliptical to ovoidal outline in dorsoventral view. Apex is broadly rounded with a short, wide and blunt apical horn which has a closed distal end. Antapex broadly rounded to slightly asymmetrical with small variably developed antapical horns. Endocyst is thick and visible and its outline follows the pericyst but lacks horns. Epicyst and hypocyst approximately equal in
length. Wall is two layered – periphragm thin, delicate and sparsely scabrate to finely granulate; endophragm smooth to punctuate and thicker and more discernible than periphragm, usually bearing short, long or irregular folds. Maximum wall separation is at apical and antapical areas. In nearly all specimens observed, the height exceeds the width.
Archeopyle: intercalary (type 2a), operculum usually free or remains attached
Paratabulation: no indication and only indicated by archeopyle and occasionally with faint paracingulum.
Dimensions:
Holotype: pericyst length 58 µm, breadth 48 µm, endocyst length 47 µm, breadth 40 µm, apical horn 8.5 µm in length.
20 specimens measured: Pericyst length 57 (64) 74 µm, breadth 46 (50.5) 55 µm, endocyst length 40 (51) 60 µm, breadth 35 (44) 53 µm,
apical horn 6 (10) 14 µm
Affinities/Comparison:
This species is distinguished by its elliptical to oval shape with much reduced antapical horns. Eurydinium ellipticum Mao & Mohr (1992) from the Maastrichtian differs in having no apical or antapical horns, in its larger size, and by both periphragm and endophragm being thin. This species is closely resembles Manumiella druggii (Stover 1974) Bujak & Davies 1983. The new species differs by being almost half the size of
M. druggii (width 92–103 mm; length 104–122 mm), irregularly granulate and also having the endoblast consistently separated laterally. Manumiella seelandica (Lange 1969) Fairth 1987 differs in having a pointed apical protrusion and large hypocyst, and has a relatively small, distally pointed left antapical horn whereas the right antapical horn is reduced. Fairth (1987) made M. seelandica a junior synonym of M. druggii. However, Thorn et al. (2009) retained M. druggii as a separate species from M. seelandica.
Holotype: Vieira, M. et al., 2018, Plate 3, figure 9
Type locality: southern part of the Ormen Lange field (Norway) over the Danian-aged reservoir
Local stratigraphical range: Danian (Early Paleocene)
Original description: Vieira, M. et al., 2018:
Diagnosis:
Pericyst circumcavate peridinoid to deflandreoid, being elliptical to ovoidal outline in dorsoventral view. Apex is broadly rounded with a short, wide and blunt apical horn which has a closed distal end. Antapex broadly rounded to slightly asymmetrical with small variably developed antapical horns. Endocyst is thick and visible and its outline follows the pericyst but lacks horns. Epicyst and hypocyst approximately equal in
length. Wall is two layered – periphragm thin, delicate and sparsely scabrate to finely granulate; endophragm smooth to punctuate and thicker and more discernible than periphragm, usually bearing short, long or irregular folds. Maximum wall separation is at apical and antapical areas. In nearly all specimens observed, the height exceeds the width.
Archeopyle: intercalary (type 2a), operculum usually free or remains attached
Paratabulation: no indication and only indicated by archeopyle and occasionally with faint paracingulum.
Dimensions:
Holotype: pericyst length 58 µm, breadth 48 µm, endocyst length 47 µm, breadth 40 µm, apical horn 8.5 µm in length.
20 specimens measured: Pericyst length 57 (64) 74 µm, breadth 46 (50.5) 55 µm, endocyst length 40 (51) 60 µm, breadth 35 (44) 53 µm,
apical horn 6 (10) 14 µm
Affinities/Comparison:
This species is distinguished by its elliptical to oval shape with much reduced antapical horns. Eurydinium ellipticum Mao & Mohr (1992) from the Maastrichtian differs in having no apical or antapical horns, in its larger size, and by both periphragm and endophragm being thin. This species is closely resembles Manumiella druggii (Stover 1974) Bujak & Davies 1983. The new species differs by being almost half the size of
M. druggii (width 92–103 mm; length 104–122 mm), irregularly granulate and also having the endoblast consistently separated laterally. Manumiella seelandica (Lange 1969) Fairth 1987 differs in having a pointed apical protrusion and large hypocyst, and has a relatively small, distally pointed left antapical horn whereas the right antapical horn is reduced. Fairth (1987) made M. seelandica a junior synonym of M. druggii. However, Thorn et al. (2009) retained M. druggii as a separate species from M. seelandica.