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Petalodinium granulatum
From Fensome et al., 2019:
Petalodinium granulatum (Morgenroth, 1966a, p.12, pl.2, fig.10) Fensome et al., 2019a, p.57. Holotype: Morgenroth, 1966a, pl.2, fig.10; Fensome et al., 2019a, fig.20P. Originally Canningia, subsequently Canningia?, thirdly (and now)
Petalodinium?. Questionable assignment: Fensome et al. (2019a. p.57). Age: Early Eocene.
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Original description: [Morgenroth, 1966, p. 12]: (Translation: LPP):
Description:
Dark-brown shell rounded pentadonal in outline, dorsoventrally flattened. Apex marked by a very small, blunted horn. The two lateral horns are of unequal length. Shell surface granulate. Girdle furrow not indicated. Holotype with wide, ellipsoidal pylome.
Dimensions:
Holotype - length 90 µm, breadth 78 µm, pylome c. 31x42 µm.
Paratype 1 - length 81 µm, breadth 70 µm; Paratype 2 - length 112 µm, breadth 87 µm.
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Comments Fensome et al., 2019a:
Morgenroth (1966, p. 12) provided the following diagnosis and description.
"Diagnosis: A species of the genus Canningia with a thick-walled, strongly granulate shell. Description: The dorsoventrally compressed, thick, dark brown shell has a rounded-pentagonal outline. The apical pole is distinguished by a very short, more or less truncated horn. The two short, broad antapical horns are of unequal length. The whole shell has a strong granulation. The girdle furrow [paracingulum] is not present. The holotype has a broad ellipse-like pylome [archaeopyle] below the apical horn."
[Translation; paragraphs joined]
Although the detailed morphology of the holotype is unclear from the single image of Morgenroth (1966), the shape and probable intercalary nature of the archaeopyle (as Morgenroth noted, it is “below the apical horn”) and the suggestion of an endophragm in one of the antapical horns suggest that it is a wetzelielloidean. If wetzelielloidean affinity is confirmed, the archaeopyle would be lati-epeliform, and hence we provisionally transfer this species to Petalodinium. We recommend that the name be restricted to the holotype.
Stratigraphical occurrence. Morgenroth (1966) recovered this species from the Lower Eocene of northern Germany.
Petalodinium granulatum (Morgenroth, 1966a, p.12, pl.2, fig.10) Fensome et al., 2019a, p.57. Holotype: Morgenroth, 1966a, pl.2, fig.10; Fensome et al., 2019a, fig.20P. Originally Canningia, subsequently Canningia?, thirdly (and now)
Petalodinium?. Questionable assignment: Fensome et al. (2019a. p.57). Age: Early Eocene.
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Original description: [Morgenroth, 1966, p. 12]: (Translation: LPP):
Description:
Dark-brown shell rounded pentadonal in outline, dorsoventrally flattened. Apex marked by a very small, blunted horn. The two lateral horns are of unequal length. Shell surface granulate. Girdle furrow not indicated. Holotype with wide, ellipsoidal pylome.
Dimensions:
Holotype - length 90 µm, breadth 78 µm, pylome c. 31x42 µm.
Paratype 1 - length 81 µm, breadth 70 µm; Paratype 2 - length 112 µm, breadth 87 µm.
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Comments Fensome et al., 2019a:
Morgenroth (1966, p. 12) provided the following diagnosis and description.
"Diagnosis: A species of the genus Canningia with a thick-walled, strongly granulate shell. Description: The dorsoventrally compressed, thick, dark brown shell has a rounded-pentagonal outline. The apical pole is distinguished by a very short, more or less truncated horn. The two short, broad antapical horns are of unequal length. The whole shell has a strong granulation. The girdle furrow [paracingulum] is not present. The holotype has a broad ellipse-like pylome [archaeopyle] below the apical horn."
[Translation; paragraphs joined]
Although the detailed morphology of the holotype is unclear from the single image of Morgenroth (1966), the shape and probable intercalary nature of the archaeopyle (as Morgenroth noted, it is “below the apical horn”) and the suggestion of an endophragm in one of the antapical horns suggest that it is a wetzelielloidean. If wetzelielloidean affinity is confirmed, the archaeopyle would be lati-epeliform, and hence we provisionally transfer this species to Petalodinium. We recommend that the name be restricted to the holotype.
Stratigraphical occurrence. Morgenroth (1966) recovered this species from the Lower Eocene of northern Germany.