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Gonyaulacysta indicosa
Gonyaulacysta indicosa Brideaux, 1971, nom. subst. pro Palaeoperidinium granulatum C. Singh, 1964
As Gonyaulacysta granulata it would have been a jr. homonym of Gonyaulacysta granulata (Klement, 1960) Sarjeant, 1969.
Now Apteodinium? indicosum. Originally Palaeoperidinium granulatum, subsequently Gonyaulacysta indicosa, thirdly (and now) Apteodinium? indicosum.
Holotype: C. Singh, 1964, pl.18, figs.2-3
Age: Middle-Late Albian
Original description: Singh 1964, p. 135: Paleoperidinium granulatum
Test nearly cingular, approximately as long as broad; apical horn averiging 1/5 of the total length, solid to partly solid, short and conical, arising abruptly from the epitheca; a spirally winding membraneous structure commonly present on the apical horn; body distinctly granulose, the equatorial girdle in the middle marked by two prominent lines bearing longer spinules; no plates or longitudinal furrow visible; one longitudinal fold and two horizontal folds, one on each surface usually present.
Size range:
Total length (including apical horn) 96 to 115Ám (Holotype 100Ám)
Length of the test 80 to 89Ám (Holotype 82Ám)
Breadth of the test 80 to 88Ám (Holotype 83Ám)
Length of the apical horn 16 to 26 Ám (Holotype 18Ám)
Distribution: Middle Albian. Common in the shale member of the Clearwater Formation and the lower grand Rapids Formation.
Remarks: Palaeoperidinium nudum DOWNIE, 1957, can be distinguished from P. granulatum n. sp. by its longer apical horn, which is 1/3 of the total length of the body, elongated test, and smooth transparent wall. P. ventriosum DEFLANDRE, 1935, has a much smaller apical horn compared with the size of the body and has over-all dimensions smaller than P. granulatum n. sp.
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Discussion: Brideaux 1971, p. 83: Gonyaulacysta indicosa.
The new specific epithet is necessary to avoid creating a junior homynym of Gonyaulacysta granulata (KLEMENT) SARJEANT 1969, P. 9. Gonyaulacysta indicosa nom. nov. resembles the generic concept of Gonyaulacysta in shape, possession of a precingular archeopyle, and a faint, although not clearly
definable, tabulation referable to that genus.
Dimensions: On 2 measured specimens respectively: length, 80µ and 119µ ; width, 84µ and 112µ ; length of apical horn, 7µ and 14µ
Distribution: SINGH (1964) records the form from the middle Albian of east-central Alberta;
specimens recorded here from the Joli Fou Formation, Battle Lake well. Late Albian.
As Gonyaulacysta granulata it would have been a jr. homonym of Gonyaulacysta granulata (Klement, 1960) Sarjeant, 1969.
Now Apteodinium? indicosum. Originally Palaeoperidinium granulatum, subsequently Gonyaulacysta indicosa, thirdly (and now) Apteodinium? indicosum.
Holotype: C. Singh, 1964, pl.18, figs.2-3
Age: Middle-Late Albian
Original description: Singh 1964, p. 135: Paleoperidinium granulatum
Test nearly cingular, approximately as long as broad; apical horn averiging 1/5 of the total length, solid to partly solid, short and conical, arising abruptly from the epitheca; a spirally winding membraneous structure commonly present on the apical horn; body distinctly granulose, the equatorial girdle in the middle marked by two prominent lines bearing longer spinules; no plates or longitudinal furrow visible; one longitudinal fold and two horizontal folds, one on each surface usually present.
Size range:
Total length (including apical horn) 96 to 115Ám (Holotype 100Ám)
Length of the test 80 to 89Ám (Holotype 82Ám)
Breadth of the test 80 to 88Ám (Holotype 83Ám)
Length of the apical horn 16 to 26 Ám (Holotype 18Ám)
Distribution: Middle Albian. Common in the shale member of the Clearwater Formation and the lower grand Rapids Formation.
Remarks: Palaeoperidinium nudum DOWNIE, 1957, can be distinguished from P. granulatum n. sp. by its longer apical horn, which is 1/3 of the total length of the body, elongated test, and smooth transparent wall. P. ventriosum DEFLANDRE, 1935, has a much smaller apical horn compared with the size of the body and has over-all dimensions smaller than P. granulatum n. sp.
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Discussion: Brideaux 1971, p. 83: Gonyaulacysta indicosa.
The new specific epithet is necessary to avoid creating a junior homynym of Gonyaulacysta granulata (KLEMENT) SARJEANT 1969, P. 9. Gonyaulacysta indicosa nom. nov. resembles the generic concept of Gonyaulacysta in shape, possession of a precingular archeopyle, and a faint, although not clearly
definable, tabulation referable to that genus.
Dimensions: On 2 measured specimens respectively: length, 80µ and 119µ ; width, 84µ and 112µ ; length of apical horn, 7µ and 14µ
Distribution: SINGH (1964) records the form from the middle Albian of east-central Alberta;
specimens recorded here from the Joli Fou Formation, Battle Lake well. Late Albian.