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Mancodinium semitabulatum ssp. glabrum
Mancodinium semitabulatum ssp. glabrum (Below, 1987); Lentin and Williams, 1989
Originally Mancodinium semitabulatum var. glabrum, subsequently (and now) Mancodinium semitabulatum ssp. glabrum.
Holotype: Below, 1987b, pl. 5, fig. 17-22, 25
Locus typicus: Marloffstein clay pit, Franconia, Germany
Stratum typicum: Late Pliensbachian
Translation Below, 1987: Translation Bureau, Secretary of State Canada, 1988
Original description: Below, 1987, p. 27
A variant of the species Mancodinium semitabulatum with a scabrate to densely fine-grained or glabrous surface without intraareate ornament, nonareate; areation formula PR, 4", 4a, 7"", as, NRc/ Xc, NR""", NR"""", NRs/Xs.
Dimensions: Holotype: length 57 µm, breadth 46 µm, thickness 42 µm.
Remarks:
Below, 1987, p. 27: The surface structure and the coating of intraareate gemmae are variable in Mancodinium semitabulatum. Thus, alongside of the typical scabrate surface, we find also reticulate, densely fine-grained, or glabrous surfaces. The tubercles can be complete or locally reduced. Plate 5, fig. 17-22 and 25 show this variety without ornament (var. glabrum). The epicystal areation is distinctly recognizable from the archeopyle sutures. But hypocystal areation, marked in the type form of Mancodinium semitabulatum by limbi between intraareate tubercles, is absent. Transitional forms with only traces of very low tubercles (pl. 5, fig. 20-21, 24) connect the varieties. Mancodinium semitabulatum var. glabrum could easily be confused with Maturodinium inornatum, which is also free of ornament, but has hypocystal fines and a different archeopyle.
Originally Mancodinium semitabulatum var. glabrum, subsequently (and now) Mancodinium semitabulatum ssp. glabrum.
Holotype: Below, 1987b, pl. 5, fig. 17-22, 25
Locus typicus: Marloffstein clay pit, Franconia, Germany
Stratum typicum: Late Pliensbachian
Translation Below, 1987: Translation Bureau, Secretary of State Canada, 1988
Original description: Below, 1987, p. 27
A variant of the species Mancodinium semitabulatum with a scabrate to densely fine-grained or glabrous surface without intraareate ornament, nonareate; areation formula PR, 4", 4a, 7"", as, NRc/ Xc, NR""", NR"""", NRs/Xs.
Dimensions: Holotype: length 57 µm, breadth 46 µm, thickness 42 µm.
Remarks:
Below, 1987, p. 27: The surface structure and the coating of intraareate gemmae are variable in Mancodinium semitabulatum. Thus, alongside of the typical scabrate surface, we find also reticulate, densely fine-grained, or glabrous surfaces. The tubercles can be complete or locally reduced. Plate 5, fig. 17-22 and 25 show this variety without ornament (var. glabrum). The epicystal areation is distinctly recognizable from the archeopyle sutures. But hypocystal areation, marked in the type form of Mancodinium semitabulatum by limbi between intraareate tubercles, is absent. Transitional forms with only traces of very low tubercles (pl. 5, fig. 20-21, 24) connect the varieties. Mancodinium semitabulatum var. glabrum could easily be confused with Maturodinium inornatum, which is also free of ornament, but has hypocystal fines and a different archeopyle.