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Chatangiella vnigrii ssp. vnigrii
Chatangiella vnigrii ssp. vnigrii
Autonym
Holotype: Vozzhennikova, 1967, pl.109, figs.2a-b; Lentin and Vozzhennikova, 1990, pl.5, figs.4-5
Locus typicus: Siberia, Khatanga depression
Stratum typicum: Santonian
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Original description as Cooksoniella vnigrii: [Vozzhennikova, 1967, p. 185]: (Translation: Lentin and Vozzhennikova, 1990):
Description:
Theca elongated along the longitudinal axis, with convex equatorial part and some tapering at the level of the upper and lower boundaries of the internal body. Theca divided into two equal parts. Epitheca broad and rounded anteriorly to form a straight "shoulder" to the outline.
Apical horn short, conical, somewhat bent and bluntly rounded at the distal end. Hypotheca with straight or slightly convex walls posteriorly and with its posterior margin truncated or curved as a result of the formation of the two antapical horns of different size. One horn is short, broadly triangular and rounded at the end, the other is longer, triangular and acutely pointed.
Transverse furrow equatorial, annulate. Between the ends of the furrow, on the ventral side, there is a depression which extends a little way onto the epitheca and ends at the antapex of the hypotheca. This depression corresponds in position to the longitudinal furrow.
The internal body is compressed so that its width exceeds its length and the two sides are closely applied to the lateral walls of the theca. Surface of internal body granulate, thickness of wall uniform or slightly greater towards the poles.
Thecal surface punctate, divided into fields by coarse spines. Similar spines occur on the edge of the transverse furrow, where they are interrupted in places which apparently correspond to the position of the sutures. Pylome of rounded hexagonal form.
Dimensions:
Holotype - length of pericyst 92 µm, width 49 µm, width of paracingulum about 6 µm; length of endocyst 42 µm, width 48 µm.
Range, length of pericyst 100-103 µm, width 49-62 µm, width of paracingulum about 6 µm; length of endocyst 40-43 µm, width 49 - 62 µm.
Autonym
Holotype: Vozzhennikova, 1967, pl.109, figs.2a-b; Lentin and Vozzhennikova, 1990, pl.5, figs.4-5
Locus typicus: Siberia, Khatanga depression
Stratum typicum: Santonian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description as Cooksoniella vnigrii: [Vozzhennikova, 1967, p. 185]: (Translation: Lentin and Vozzhennikova, 1990):
Description:
Theca elongated along the longitudinal axis, with convex equatorial part and some tapering at the level of the upper and lower boundaries of the internal body. Theca divided into two equal parts. Epitheca broad and rounded anteriorly to form a straight "shoulder" to the outline.
Apical horn short, conical, somewhat bent and bluntly rounded at the distal end. Hypotheca with straight or slightly convex walls posteriorly and with its posterior margin truncated or curved as a result of the formation of the two antapical horns of different size. One horn is short, broadly triangular and rounded at the end, the other is longer, triangular and acutely pointed.
Transverse furrow equatorial, annulate. Between the ends of the furrow, on the ventral side, there is a depression which extends a little way onto the epitheca and ends at the antapex of the hypotheca. This depression corresponds in position to the longitudinal furrow.
The internal body is compressed so that its width exceeds its length and the two sides are closely applied to the lateral walls of the theca. Surface of internal body granulate, thickness of wall uniform or slightly greater towards the poles.
Thecal surface punctate, divided into fields by coarse spines. Similar spines occur on the edge of the transverse furrow, where they are interrupted in places which apparently correspond to the position of the sutures. Pylome of rounded hexagonal form.
Dimensions:
Holotype - length of pericyst 92 µm, width 49 µm, width of paracingulum about 6 µm; length of endocyst 42 µm, width 48 µm.
Range, length of pericyst 100-103 µm, width 49-62 µm, width of paracingulum about 6 µm; length of endocyst 40-43 µm, width 49 - 62 µm.