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Isabelidinium weidichii
Isabelidinium weidichii Kirsch, 1991
Holotype: Kirsch, 1991, pl.21, fig.7
Paratype: Kirsch, 1991
Locus typicus: Wehrprofil, Bavaria, Germany
Stratum typicum: Early Maastrichtian
Translation Kirsch, 1991: LPP
Original diagnosis: Kirsch, 1991, p. 107
Dorsoventrally flattened, bicavate to circumcavate, intermediate cyst with a ellipsoidal to sphaeroidal, smooth central body. The smooth pericyst is characterized by a rounded apical region and shows except the archaeopyle no indication of tabulation. A hypocystal (?) opening is rarely visibly.
Original description: Kirsch, 1991, p. 107
The usually bicavate cyst, which is longer than wide, shows a subpentagonal outline. On bicavate specimens a lateral pericoel is present. Except a weak apical protusion, no apical horn is developed. The hypocyst consists of two weak, pointed antapical processes of variable length. The left antapical horn is slightly longer. The flanks of the hypocyst a nearly straight, while those of the epicyst a convex. "Shoulders" are not developed on the epicyst. Periarchaeopyle intercalary (2a) and isotheta - isoomegaform(?), perioperculum posterior adnat. On some specimens a polygonal opening on the hypocyst was observed.
Dimensions: Range: Endocyst (LxB) 34-36 x 44-50 Ám; pericyst (LxB) 72-80 x 47-60 Ám.
Affinities:
Kirsch, 1991, p. 107: Isabelidinium weidichii differs from I. cretaceum (Cookson 1956) in the elongate form of the cyst and from I. belfastense (Cookson and Eisenack 1961) in the reduced apical horn. I. weidichii differs from I.(?) rhombovale (Cookson and Eisenack 1970) in missing the apical horn and the single antapical horn. I. korojonense (Cookson and Eisenack 1958) differs in the shape of the epicyst.
Holotype: Kirsch, 1991, pl.21, fig.7
Paratype: Kirsch, 1991
Locus typicus: Wehrprofil, Bavaria, Germany
Stratum typicum: Early Maastrichtian
Translation Kirsch, 1991: LPP
Original diagnosis: Kirsch, 1991, p. 107
Dorsoventrally flattened, bicavate to circumcavate, intermediate cyst with a ellipsoidal to sphaeroidal, smooth central body. The smooth pericyst is characterized by a rounded apical region and shows except the archaeopyle no indication of tabulation. A hypocystal (?) opening is rarely visibly.
Original description: Kirsch, 1991, p. 107
The usually bicavate cyst, which is longer than wide, shows a subpentagonal outline. On bicavate specimens a lateral pericoel is present. Except a weak apical protusion, no apical horn is developed. The hypocyst consists of two weak, pointed antapical processes of variable length. The left antapical horn is slightly longer. The flanks of the hypocyst a nearly straight, while those of the epicyst a convex. "Shoulders" are not developed on the epicyst. Periarchaeopyle intercalary (2a) and isotheta - isoomegaform(?), perioperculum posterior adnat. On some specimens a polygonal opening on the hypocyst was observed.
Dimensions: Range: Endocyst (LxB) 34-36 x 44-50 Ám; pericyst (LxB) 72-80 x 47-60 Ám.
Affinities:
Kirsch, 1991, p. 107: Isabelidinium weidichii differs from I. cretaceum (Cookson 1956) in the elongate form of the cyst and from I. belfastense (Cookson and Eisenack 1961) in the reduced apical horn. I. weidichii differs from I.(?) rhombovale (Cookson and Eisenack 1970) in missing the apical horn and the single antapical horn. I. korojonense (Cookson and Eisenack 1958) differs in the shape of the epicyst.