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Cerodinium verrucosum
From Fensome et al., 2019:
Cerodinium verrucosum (Heisecke, 1970, p.232,234, pl.9, figs.2–3; pl.10, fig.3) Lentin and Williams, 1989, p.56. Holotype: Heisecke, 1970, pl.9, fig.2; pl.10, fig.3. Originally Scriniodinium, subsequently Scriniodinium?, thirdly (and now) Cerodinium. Age: Danian.
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Original description (Heisecke, 1970) Not yet translated from Spanish
DIAGNOSIS. Cyst excavated in subcircular to rhomboidal contour composed of two layers. Endophragm
thick, opaque, infragranulated, with warty sculpture; periphragm delicate, hyaline, forming an apical horn and two small antiapical horns. In the equatorial zone, a poorly defined cingulum is observed. It has a precingular archeopyle.
HOLOTYPE. Slide 429(1), coordinates 35.7/104.2.
DIMENSIONS. Holotype: total length 84 μm, polled length 68 μm, width 67 μm, apical horn length 8 μm, greater antiapical horn length 9 μm, lesser antiapical horn length 4 μm.
DESCRIPTION. Subspherical excavated cyst with a circular to subcircular contour with a tendency to rhomboidal,
composed of two layers. The endophragm, opaque, reddish brown, presents warty sculpture; The warts are distributed in a fairly spaced and irregular manner, and the shapes of these warts are diverse, with irregular contours, in some cases elongated, with one wart joining another. The periphragm is delicate, hyaline and forms a small apical protuberance or horn and two antiapical horns, one larger than the other, also small. Both layers are separated forming a period of 1-1.5 μm. wide, except in the apical and antiapical area, where they separate to form the horns. In the equatorial zone, irregular thickenings of the wall are observed, which would indicate the presence of a little characteristic or defined angle. It has a precingular archeopyle. irregular pentagonal.
DIMENSIONS. Total length 84-86 μm, length (without horns) 64-68 μm, width 67-68 μm, apical horn length 8-10 μm, length of major antiapical horn 9-15 μm, length of the minor antiapical horn 4-7 μm, Number of specimens measured: 2.
STUDY MATERIAL. slide 67( 4 ), coordinates 46.2/111.8 and slide 429( 1 ), coordinates
35.7/104.2.
DISCUSSION. This new species differs from those observed corresponding to the same genus, mainly in the warty structure of the endophragm and the great contrast between the thick and opaque endophragm and the delicate and hyaline periphragm. Deflandrea endopapillata Archangelsky, 1959, is the only species comparable to the one described here because of its endophragm provided with papillae. However, Scriniodinium verrucosum differs from this form due to the position of the archaeopil; The horns of the new species are relatively small, the periphragm is smooth (it does not present more condensed granules in the horns and in the pericingular region as in D. endopapillata) and the size is smaller.
HORIZON. Samples MH6 and MH2.
DERIVATIO NOMINIS. From the Latin verrucosus, warty, referring to the warty sculpture of the endophragm.
Cerodinium verrucosum (Heisecke, 1970, p.232,234, pl.9, figs.2–3; pl.10, fig.3) Lentin and Williams, 1989, p.56. Holotype: Heisecke, 1970, pl.9, fig.2; pl.10, fig.3. Originally Scriniodinium, subsequently Scriniodinium?, thirdly (and now) Cerodinium. Age: Danian.
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Original description (Heisecke, 1970) Not yet translated from Spanish
DIAGNOSIS. Cyst excavated in subcircular to rhomboidal contour composed of two layers. Endophragm
thick, opaque, infragranulated, with warty sculpture; periphragm delicate, hyaline, forming an apical horn and two small antiapical horns. In the equatorial zone, a poorly defined cingulum is observed. It has a precingular archeopyle.
HOLOTYPE. Slide 429(1), coordinates 35.7/104.2.
DIMENSIONS. Holotype: total length 84 μm, polled length 68 μm, width 67 μm, apical horn length 8 μm, greater antiapical horn length 9 μm, lesser antiapical horn length 4 μm.
DESCRIPTION. Subspherical excavated cyst with a circular to subcircular contour with a tendency to rhomboidal,
composed of two layers. The endophragm, opaque, reddish brown, presents warty sculpture; The warts are distributed in a fairly spaced and irregular manner, and the shapes of these warts are diverse, with irregular contours, in some cases elongated, with one wart joining another. The periphragm is delicate, hyaline and forms a small apical protuberance or horn and two antiapical horns, one larger than the other, also small. Both layers are separated forming a period of 1-1.5 μm. wide, except in the apical and antiapical area, where they separate to form the horns. In the equatorial zone, irregular thickenings of the wall are observed, which would indicate the presence of a little characteristic or defined angle. It has a precingular archeopyle. irregular pentagonal.
DIMENSIONS. Total length 84-86 μm, length (without horns) 64-68 μm, width 67-68 μm, apical horn length 8-10 μm, length of major antiapical horn 9-15 μm, length of the minor antiapical horn 4-7 μm, Number of specimens measured: 2.
STUDY MATERIAL. slide 67( 4 ), coordinates 46.2/111.8 and slide 429( 1 ), coordinates
35.7/104.2.
DISCUSSION. This new species differs from those observed corresponding to the same genus, mainly in the warty structure of the endophragm and the great contrast between the thick and opaque endophragm and the delicate and hyaline periphragm. Deflandrea endopapillata Archangelsky, 1959, is the only species comparable to the one described here because of its endophragm provided with papillae. However, Scriniodinium verrucosum differs from this form due to the position of the archaeopil; The horns of the new species are relatively small, the periphragm is smooth (it does not present more condensed granules in the horns and in the pericingular region as in D. endopapillata) and the size is smaller.
HORIZON. Samples MH6 and MH2.
DERIVATIO NOMINIS. From the Latin verrucosus, warty, referring to the warty sculpture of the endophragm.