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Dracodinium politum
Dracodinium politum Bujak in Bujak et al., 1980
NOW Rhadinodinium. Originally Dracodinium, subsequently (and now) Rhadinodinium.
Aside from the holotype of Dracodinium (now Rhadinodinium) politum being incorrectly indicated in Williams et al. (1998), confusion is caused by the fact that the plates and captions in the originally-issued protologue publication were mixed up. Hence, in Williams and Downie (1966b, original issue), the holotype appears as pl.19, fig.9, opposite the caption labelled plate 19 but clearly intended as caption to the plate labelled 20; the correct caption for the plate labelled 19 is opposite the plate labelled 20. In the 1983 issue of the monograph, these problems were corrected and the holotype of Dracodinium (now Rhadinodinium) politum is pl.20, fig.9.
Holotype: Williams and Downie, 1966b, pl.19, fig.9 (see discussion above), as Wetzeliella glabra; not Bujak et al., 1980, pl.11, fig.1 as indicated in Williams et al. (1998, p.204).
Locus typicus: Isle of Sheppey, Kent, England
Stratum typicum: Early Eocene
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Dracodinium politum Bujak et al., 1980, has a subtriangular pericyst with rounded apex, occasionally with the suggestion of a short apical horn. Pericingular and left antapical horns well developed. Length of epipericyst considerably shorter than hypopericyst. Periphragm smooth to chagrinate. Size: Pericyst length 130-151 µm, width 140-168 µm, endocyst length 66-80 µm, width 69-76 µm.
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Original diagnosis: Bujak in Bujak et al., 1980, p. 29
Pericyst ambitus subtriangular with a convex epipericyst. Apex rounded, occasionally with the suggestion of a small apical protrusion. Pericingular horns and left antapical horn well developed. Right antapical horn absent or denoted by a slight swelling of the pericyst. Length of epipericyst considerably less than length of hypopericyst. Endocyst ambitus circular. Pericoel well developed, being broad and continuous in ambital view. Periphragm smooth to chagrinate, without processes. Endophragm smooth or granulate, occasionally verrucate around the ambital periphery. Paratabulation indeterminate. Pericingulum only visible at the extremities of the pericingular horns. Perisulcus not seen. Periarchaeopyle resulting from the loss of the second anterior intercalary paraplate 2a. Perioperculum detached. Endoarchaeopyle of similar size and shape to the periarchaeopyle posteriorly, but does not underlie it anteriorly. Endoperculum detached.
Dimensions. Pericyst length 130-151 µm, breadth 140-168 µm. Endocyst length 66-80 µm, breadth 69-76 µm.
NOW Rhadinodinium. Originally Dracodinium, subsequently (and now) Rhadinodinium.
Aside from the holotype of Dracodinium (now Rhadinodinium) politum being incorrectly indicated in Williams et al. (1998), confusion is caused by the fact that the plates and captions in the originally-issued protologue publication were mixed up. Hence, in Williams and Downie (1966b, original issue), the holotype appears as pl.19, fig.9, opposite the caption labelled plate 19 but clearly intended as caption to the plate labelled 20; the correct caption for the plate labelled 19 is opposite the plate labelled 20. In the 1983 issue of the monograph, these problems were corrected and the holotype of Dracodinium (now Rhadinodinium) politum is pl.20, fig.9.
Holotype: Williams and Downie, 1966b, pl.19, fig.9 (see discussion above), as Wetzeliella glabra; not Bujak et al., 1980, pl.11, fig.1 as indicated in Williams et al. (1998, p.204).
Locus typicus: Isle of Sheppey, Kent, England
Stratum typicum: Early Eocene
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Dracodinium politum Bujak et al., 1980, has a subtriangular pericyst with rounded apex, occasionally with the suggestion of a short apical horn. Pericingular and left antapical horns well developed. Length of epipericyst considerably shorter than hypopericyst. Periphragm smooth to chagrinate. Size: Pericyst length 130-151 µm, width 140-168 µm, endocyst length 66-80 µm, width 69-76 µm.
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Original diagnosis: Bujak in Bujak et al., 1980, p. 29
Pericyst ambitus subtriangular with a convex epipericyst. Apex rounded, occasionally with the suggestion of a small apical protrusion. Pericingular horns and left antapical horn well developed. Right antapical horn absent or denoted by a slight swelling of the pericyst. Length of epipericyst considerably less than length of hypopericyst. Endocyst ambitus circular. Pericoel well developed, being broad and continuous in ambital view. Periphragm smooth to chagrinate, without processes. Endophragm smooth or granulate, occasionally verrucate around the ambital periphery. Paratabulation indeterminate. Pericingulum only visible at the extremities of the pericingular horns. Perisulcus not seen. Periarchaeopyle resulting from the loss of the second anterior intercalary paraplate 2a. Perioperculum detached. Endoarchaeopyle of similar size and shape to the periarchaeopyle posteriorly, but does not underlie it anteriorly. Endoperculum detached.
Dimensions. Pericyst length 130-151 µm, breadth 140-168 µm. Endocyst length 66-80 µm, breadth 69-76 µm.