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Oligosphaeridium poculum
Oligosphaeridium poculum Jain, 1977
Holotype: Jain 1977b: Pl. 1, fig. 3;
Locus typicus: Kallakkudi Limestone Quarry II, Dalmiapuram, South India.
Stratum typicum: Grey Shale Member, Dalmiapuram Formation, Early Albian.
Age: Early Albian
Original diagnosis: Jain 1977b, p. 181
Cyst spherical, double-walled; periphragm covered with vase or cup shaped processes with narrow proximal and wider distal end, distally open, with recurved or denticulate margin. Proximal contact with periphragm form thick ring at the base; distinct hole seen when viewed through tube. Tabulation typical of the genus. Archaeopyle apical.
Measurements Holotype Range
Cyst diameter without processes 80 µm 50-80 µm
Process height 6 µm 6-10 µm
Process distal up to width 24 µm 8-24 µm
Process proximal up to width 16 µm 6-16 µm
Comparison: Jain 1977b, p. 181
O. poculum sp. nov. is characterized by its typical vase or cup shaped processes without stem. It can only be compared with O. albertense (Pocock) Davey & Williams (1966) in having a few distally broad processes with very small stem.
Polystephanephorus sp. cf. P. urnafarmis (Cookson) Sarjeant described by Singh (1971, p. 341, pl. 57, figs. 1-2) and P. urnaformis (Cookson Sarjeant by Pocock (in Press, pl. 1, fig. 5 from Albian of Canada appear to be synonymous. The specimens need critical re-examination.
Holotype: Jain 1977b: Pl. 1, fig. 3;
Locus typicus: Kallakkudi Limestone Quarry II, Dalmiapuram, South India.
Stratum typicum: Grey Shale Member, Dalmiapuram Formation, Early Albian.
Age: Early Albian
Original diagnosis: Jain 1977b, p. 181
Cyst spherical, double-walled; periphragm covered with vase or cup shaped processes with narrow proximal and wider distal end, distally open, with recurved or denticulate margin. Proximal contact with periphragm form thick ring at the base; distinct hole seen when viewed through tube. Tabulation typical of the genus. Archaeopyle apical.
Measurements Holotype Range
Cyst diameter without processes 80 µm 50-80 µm
Process height 6 µm 6-10 µm
Process distal up to width 24 µm 8-24 µm
Process proximal up to width 16 µm 6-16 µm
Comparison: Jain 1977b, p. 181
O. poculum sp. nov. is characterized by its typical vase or cup shaped processes without stem. It can only be compared with O. albertense (Pocock) Davey & Williams (1966) in having a few distally broad processes with very small stem.
Polystephanephorus sp. cf. P. urnafarmis (Cookson) Sarjeant described by Singh (1971, p. 341, pl. 57, figs. 1-2) and P. urnaformis (Cookson Sarjeant by Pocock (in Press, pl. 1, fig. 5 from Albian of Canada appear to be synonymous. The specimens need critical re-examination.