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Spinidinium rallum
From Fensome et al., 2019:
Spinidinium ?rallum Heisecke, 1970, p.226,228, pl.1, figs.1–2; pl.2, fig.1. Originally Spinidinium, subsequently Magallanesium, thirdly (and now) Spinidinium? Questionable assignment: Sluijs et al. (2009, p.48). Age: Danian.
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Original description (Heisecke, 1970) Not yet translated from Spanish
DIAGNOSIS. Ovoid, excavated cyst. The surface is covered with sharp spines, more numerous than usual for the genus, and distributed irregularly and at intervals along the body, generally aligned and occasionally joined by septa. The periphragm forms an apical horn and an antiapical protuberance; it has a slightly indented angle. No aperture was observed.
HOLOTYPE: Preparation 67(6), coordinates 46.6/111.3. Horns) 24 µm, width 32 µm, length of apical horn 16 µm, length of antiapical protuberance 5.5 µm.DESCRIPTION. Excavated cyst of varied shape, generally ovoid. The outline is oval to irregular pentagonal, exceptionally triangular or conical. The surface is covered with a few long, sharp spines, which are preferentially distributed along lines forming borders between plates; in some cases, they are joined by septa. The wall is composed of two layers; the periphragm, which forms the spines, comprises a pyramidal apical horn that generally culminates in an apical pore and an antiapical protuberance that culminates in a spine. The endophragm forms a capsule that occupies the entire width and slightly more than half the length of the cyst. The reflected tabulation is unclear, making it difficult to establish; however, in the holotype, 5 plates are clearly distinguishable in the apical zone. The body shows evidence of a precingular and a postcingular area separated by a series of lower plates that correspond to the cingulate cortex. However, the number of plates in each series could not be determined. No openings were observed.
DIMENSIONS. Total length 34.5-48 μm, length (without horns) 20-31 μm, width 24-34.5 μm, apical horn length 11.5-22 μm, antiapical protuberance length 1-19 μm. Number of specimens measured: 14.
MAIN MATERIAL STUDIED. Preparation 67(4), coordinates 53.3/108.6; 44.2/11.8; preparation 67(6), coordinates 46.4/111.3; 44.1/110.8; Preparation 429(4), coordinates 49/107.5.
DISCUSSION Y COMPARACIONES. Se ha incluido Ia nueva · especie en el genero Spinidinium por presentar en lugar : de cuernos antiapica:les, una prominencia o proyección y pbr ten er ·Ia supetfide cubierta por espinas. Sin embargo las especies anteriormente descriptas corresponpondientes
a este genero tienen Ia superficie mas densamente cubierta por espinas y estas son mas cortas, por lo que la nueva especie no puede ser comparada con ninguna de aquellas. Varios de los ejemplares
de Deflandrea descriptos en este trabajo tienen las espinas muy similares a las de la nueva especie. Sin embargo, por otras caracterfsticas ( ver las Observaciones hechas para Deflandrea irmoechinata)
se concluye que estas formas no pueden pertenecr a una misma especie. La nueva especie difiere de Deflandrea cf. macmurdoensis y Deflandrea sp. I en que ambas poseen un dngulo bien marcado,
cuernos antiapicales, no presentan division en areas o campos y D. cf. macmurdoensis presenta arqueopilo intercalar, ad,emas . de un aspecto externo ( forma, dimensiones) diferente.
Spinidinium ?rallum Heisecke, 1970, p.226,228, pl.1, figs.1–2; pl.2, fig.1. Originally Spinidinium, subsequently Magallanesium, thirdly (and now) Spinidinium? Questionable assignment: Sluijs et al. (2009, p.48). Age: Danian.
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Original description (Heisecke, 1970) Not yet translated from Spanish
DIAGNOSIS. Ovoid, excavated cyst. The surface is covered with sharp spines, more numerous than usual for the genus, and distributed irregularly and at intervals along the body, generally aligned and occasionally joined by septa. The periphragm forms an apical horn and an antiapical protuberance; it has a slightly indented angle. No aperture was observed.
HOLOTYPE: Preparation 67(6), coordinates 46.6/111.3. Horns) 24 µm, width 32 µm, length of apical horn 16 µm, length of antiapical protuberance 5.5 µm.DESCRIPTION. Excavated cyst of varied shape, generally ovoid. The outline is oval to irregular pentagonal, exceptionally triangular or conical. The surface is covered with a few long, sharp spines, which are preferentially distributed along lines forming borders between plates; in some cases, they are joined by septa. The wall is composed of two layers; the periphragm, which forms the spines, comprises a pyramidal apical horn that generally culminates in an apical pore and an antiapical protuberance that culminates in a spine. The endophragm forms a capsule that occupies the entire width and slightly more than half the length of the cyst. The reflected tabulation is unclear, making it difficult to establish; however, in the holotype, 5 plates are clearly distinguishable in the apical zone. The body shows evidence of a precingular and a postcingular area separated by a series of lower plates that correspond to the cingulate cortex. However, the number of plates in each series could not be determined. No openings were observed.
DIMENSIONS. Total length 34.5-48 μm, length (without horns) 20-31 μm, width 24-34.5 μm, apical horn length 11.5-22 μm, antiapical protuberance length 1-19 μm. Number of specimens measured: 14.
MAIN MATERIAL STUDIED. Preparation 67(4), coordinates 53.3/108.6; 44.2/11.8; preparation 67(6), coordinates 46.4/111.3; 44.1/110.8; Preparation 429(4), coordinates 49/107.5.
DISCUSSION Y COMPARACIONES. Se ha incluido Ia nueva · especie en el genero Spinidinium por presentar en lugar : de cuernos antiapica:les, una prominencia o proyección y pbr ten er ·Ia supetfide cubierta por espinas. Sin embargo las especies anteriormente descriptas corresponpondientes
a este genero tienen Ia superficie mas densamente cubierta por espinas y estas son mas cortas, por lo que la nueva especie no puede ser comparada con ninguna de aquellas. Varios de los ejemplares
de Deflandrea descriptos en este trabajo tienen las espinas muy similares a las de la nueva especie. Sin embargo, por otras caracterfsticas ( ver las Observaciones hechas para Deflandrea irmoechinata)
se concluye que estas formas no pueden pertenecr a una misma especie. La nueva especie difiere de Deflandrea cf. macmurdoensis y Deflandrea sp. I en que ambas poseen un dngulo bien marcado,
cuernos antiapicales, no presentan division en areas o campos y D. cf. macmurdoensis presenta arqueopilo intercalar, ad,emas . de un aspecto externo ( forma, dimensiones) diferente.