Back
Operculodinium flucturum
Operculodinium fucturum Davey, 1969
Holotype: Davey, 1969, pl.2, fig.7
Paratype: Davey, 1969
Locus typicus: Northern Natal, South Africa
Stratum typicum: Maastrichtian-?Danian
Original diagnosis: Davey, 1969, p.8
Test subspherical; wall of moderate thickness bearing low vermicular ridges and tubercles. Spines numerous and arise from the surface structures. Spines of variable shape, mainly simple but sometimes joined medially; the simple spines are typically of an elongate conical form, capitate distally. Polar structures and tabulation absent. Archaeopyle precingular, of a rounded, triangular shape.
Dimensions: Holotype: central body diameter 49 by 52 Ám, length of spines up to 7 Ám. Paratype: central body diameter 42 by 45 Ám, length of spines up to 6 Ám. Range: central body diameter 42(49.9)64 Ám, maximum length of spines 5-7 Ám. Number of specinlens measured, 12.
Original description: Davey, 1969, p.8
The test wall is of moderate thickness (1 to 2 Ám) and bears many irregularly arranged vermicular ridges which may be reduced in size to simple tubercles. The ridges and tubercles give rise to the numerous spines. The spines are delicate, typically simple each with a broad base (up to 4 Ám in width), narrowing rapidly to terminate with a truncate or capitate extremity. The more broadly conical spines may be fenestrate proximally. All spines of approximately equal height; spine aligmnent is absent. The rounded, triangular shape of the cyst opening is characteristic of a precingular archaeopyle.
Affinities:
Davey, 1969, p.8: O. flucturum is similar to O. israelianum (Rossignol 1962) in overall form and basic conical shape of the spines but differs by the absence of the vermicular ornamentation. The type material of the latter species also possesses acuminate spines. O. israelianum, as described by Wall (1967) from recent Caribbean sediments, does possess capitate spines but again the characteristic ornamentation of O. flucturum is absent.
Holotype: Davey, 1969, pl.2, fig.7
Paratype: Davey, 1969
Locus typicus: Northern Natal, South Africa
Stratum typicum: Maastrichtian-?Danian
Original diagnosis: Davey, 1969, p.8
Test subspherical; wall of moderate thickness bearing low vermicular ridges and tubercles. Spines numerous and arise from the surface structures. Spines of variable shape, mainly simple but sometimes joined medially; the simple spines are typically of an elongate conical form, capitate distally. Polar structures and tabulation absent. Archaeopyle precingular, of a rounded, triangular shape.
Dimensions: Holotype: central body diameter 49 by 52 Ám, length of spines up to 7 Ám. Paratype: central body diameter 42 by 45 Ám, length of spines up to 6 Ám. Range: central body diameter 42(49.9)64 Ám, maximum length of spines 5-7 Ám. Number of specinlens measured, 12.
Original description: Davey, 1969, p.8
The test wall is of moderate thickness (1 to 2 Ám) and bears many irregularly arranged vermicular ridges which may be reduced in size to simple tubercles. The ridges and tubercles give rise to the numerous spines. The spines are delicate, typically simple each with a broad base (up to 4 Ám in width), narrowing rapidly to terminate with a truncate or capitate extremity. The more broadly conical spines may be fenestrate proximally. All spines of approximately equal height; spine aligmnent is absent. The rounded, triangular shape of the cyst opening is characteristic of a precingular archaeopyle.
Affinities:
Davey, 1969, p.8: O. flucturum is similar to O. israelianum (Rossignol 1962) in overall form and basic conical shape of the spines but differs by the absence of the vermicular ornamentation. The type material of the latter species also possesses acuminate spines. O. israelianum, as described by Wall (1967) from recent Caribbean sediments, does possess capitate spines but again the characteristic ornamentation of O. flucturum is absent.