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Operculodinium nanaconulum
Operculodinium nanaconulum Islam, 1983
Holotype: Islam, 1983, pl.3, figs.12-13
Locus typicus: Isle of Sheppey, SE England
Stratum typicum: Early Eocene
Original diagnosis: Islam, 1983, p.241
The cyst is subspherical to ellipsoidal, proximochorate and biphragmal; the endophragm is chagrinate and the periphragm is psilate; the phragma are closely adpressed exept at the bases of processes possesses numerous nontabular very short conical processes, hollow with broad base and pointed tip, closed at both ends; nearly as long as broad at bases but normally a bit longer; the archeopyle is precingular type P.
Dimensions: Holotype: cyst body 34 X 30 Ám length of processes 2-3 Ám. Range: cyst length 36(31)29 Ám breadth 31(28)24 Ám, length of processes 2-3 Ám - Specimens measured 7.
Affinities:
Islam, 1983, p.242: It differs from other species of the genus in possessing very small conical processes which may raise a question concerning its generic attribution. It is not referable to Pyridiella Cookson and Eisenack which possesses an intercalary archeopyle. It resembles Tectatodinium Wall but that genus does not bear processes.
Holotype: Islam, 1983, pl.3, figs.12-13
Locus typicus: Isle of Sheppey, SE England
Stratum typicum: Early Eocene
Original diagnosis: Islam, 1983, p.241
The cyst is subspherical to ellipsoidal, proximochorate and biphragmal; the endophragm is chagrinate and the periphragm is psilate; the phragma are closely adpressed exept at the bases of processes possesses numerous nontabular very short conical processes, hollow with broad base and pointed tip, closed at both ends; nearly as long as broad at bases but normally a bit longer; the archeopyle is precingular type P.
Dimensions: Holotype: cyst body 34 X 30 Ám length of processes 2-3 Ám. Range: cyst length 36(31)29 Ám breadth 31(28)24 Ám, length of processes 2-3 Ám - Specimens measured 7.
Affinities:
Islam, 1983, p.242: It differs from other species of the genus in possessing very small conical processes which may raise a question concerning its generic attribution. It is not referable to Pyridiella Cookson and Eisenack which possesses an intercalary archeopyle. It resembles Tectatodinium Wall but that genus does not bear processes.