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Spinidinium eggeri
Spinidinium eggeri Kirsch, 1991
Holotype: Kirsch, 1991, pl.23, fig.1; text-figs.56a-b
Age: Late Santonian
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Original description: [Kirsch, 1991]:
Spinidinium eggerii sp. nov.
Plate 23, Figs. 1-3; Figs. 56a-e
Derivation nominis: In honor of Dr. J. G. Egger.
Holotype: Specimen 170.2, EF: J 4g
Paratype: Specimen 170.2, EF: G 46/2.
Locus typicus: Diesselbach; Upper Bavaria.
Stratum typicalum: Buntmergel series; Upper Santon (asymetrica zone).
Diagnosis: Circumcavate, smooth cyst with a diamond-shaped habit and a subspheroidal, smooth central body.
Characteristic features are the acuminate, basally broadened, and often proximally connected, short spines, particularly on the cingulate. A mostly reduced right antapical horn contrasts with a relatively long, acuminate left antapical horn. Archaeopyle
intercalary, Attenuated-hexa-2a.
Description: Overall, a distinctly diamond-shaped cyst with a subspheroidal central body that is not contiguous at the sides. The tapered epicyst is strikingly trigonal in shape with straight flanks and an apical horn that is either almost completely receding or conical, ending distally bluntly. The epicyst is approximately the same length as the hypocyst, whose flanks are straight to slightly convex.
The acuminate or distally rounded, massive spines, narrowing towards the free end, are irregularly distributed and arranged in sutural rows, tracing plate boundaries. Plates 2a and 1' (KOFOID) are most clearly identified by single spines arranged in a row.
The sulcus is indicated by a process-free area. The cingulum is formed by ridges of proximally connected spines, which appear laterally separated and process-free. Archaeopyle intercalary, attenuated-hexa-2a, with posterior adnate operculum.
Tabulation: ?4', 3a, 7", xc, 5"', 2"".
Comparison: Spinidinium eggeri sp. nov. differs from Spinidinium rhombicum (COOKSON & EISENACK 1974) in its diamond-shaped habitus and finer processes. In contrast to the morphologically similar species Spinidinium mariae AURISANO 1984, the characteristic bifid and bifurcate spines are missing (AURISANO 1984: 7).
Dimensions: Holotype: Endocyst size 32 x 32 μ; Pericyst size 56 x 42 μ; length of apical horn 7 μ; length of antapical horn 10 μ; spine length max. 1.5 μ.
Variation: Total size 47-56 x 38-42 μ; size of central body 28-32 x 30-32 μ; length of apical horn 5-7 μ; length of antapical horn 7-10 μ.
Material: 10 specimens.
Occurrence: Diesselbach profile (BMS); Schußkogel profile (Amden beds).
Age: Upper Santonian (asymetrica zone).
Holotype: Kirsch, 1991, pl.23, fig.1; text-figs.56a-b
Age: Late Santonian
------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Kirsch, 1991]:
Spinidinium eggerii sp. nov.
Plate 23, Figs. 1-3; Figs. 56a-e
Derivation nominis: In honor of Dr. J. G. Egger.
Holotype: Specimen 170.2, EF: J 4g
Paratype: Specimen 170.2, EF: G 46/2.
Locus typicus: Diesselbach; Upper Bavaria.
Stratum typicalum: Buntmergel series; Upper Santon (asymetrica zone).
Diagnosis: Circumcavate, smooth cyst with a diamond-shaped habit and a subspheroidal, smooth central body.
Characteristic features are the acuminate, basally broadened, and often proximally connected, short spines, particularly on the cingulate. A mostly reduced right antapical horn contrasts with a relatively long, acuminate left antapical horn. Archaeopyle
intercalary, Attenuated-hexa-2a.
Description: Overall, a distinctly diamond-shaped cyst with a subspheroidal central body that is not contiguous at the sides. The tapered epicyst is strikingly trigonal in shape with straight flanks and an apical horn that is either almost completely receding or conical, ending distally bluntly. The epicyst is approximately the same length as the hypocyst, whose flanks are straight to slightly convex.
The acuminate or distally rounded, massive spines, narrowing towards the free end, are irregularly distributed and arranged in sutural rows, tracing plate boundaries. Plates 2a and 1' (KOFOID) are most clearly identified by single spines arranged in a row.
The sulcus is indicated by a process-free area. The cingulum is formed by ridges of proximally connected spines, which appear laterally separated and process-free. Archaeopyle intercalary, attenuated-hexa-2a, with posterior adnate operculum.
Tabulation: ?4', 3a, 7", xc, 5"', 2"".
Comparison: Spinidinium eggeri sp. nov. differs from Spinidinium rhombicum (COOKSON & EISENACK 1974) in its diamond-shaped habitus and finer processes. In contrast to the morphologically similar species Spinidinium mariae AURISANO 1984, the characteristic bifid and bifurcate spines are missing (AURISANO 1984: 7).
Dimensions: Holotype: Endocyst size 32 x 32 μ; Pericyst size 56 x 42 μ; length of apical horn 7 μ; length of antapical horn 10 μ; spine length max. 1.5 μ.
Variation: Total size 47-56 x 38-42 μ; size of central body 28-32 x 30-32 μ; length of apical horn 5-7 μ; length of antapical horn 7-10 μ.
Material: 10 specimens.
Occurrence: Diesselbach profile (BMS); Schußkogel profile (Amden beds).
Age: Upper Santonian (asymetrica zone).