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Diconodinium paucigranulatum
Diconodinium paucigranulatum Burger, 1980
Holotype: Burger, 1980, pl.44, fig.3
Age: Aptian
Original diagnosis (Burger, 1980):
Holotype: GSQ Surat 1, depth 305.3 m (100 ft 6 in); Wallumbilla Formation, Doncaster Member; Cretaceous, late Aptian (MFP 5015-1, 282/1117; CPC 16439. Pl. 44, fig. 3).
Description: Cyst biconical, epicyst longer than hypocyst, with a prominent and thin, tubular or tapering horn 8-18 p.m long; hypocyst with a similar but shorter (2-10 p.m) horn. A small intercalary archaeopyle with a triangular to hemispherical outline is formed in a few specimens. A paracingulum is vaguely indicated in several specimens; no other traces of paratabulation are visible. Cyst wall thin, sparsely and to all appearances randomly granulate.
Dimensions: Length (14 specimens) 67-85 µm, width (11 specimens) 40-56 µm.
Distribution: A rare to common species in the Odontochitina operculata Zone.
Comments: The species is a typical representative of Diconodinium. It differs from D. arcticum Manum & Cookson, 1964, in lacking a broad paracingulum and having longer horns. D. glabrum Eisenack & Cookson, 1960, displays a more or less prominent parasulcus and paracingulum. D. inflatum Eisenack & Cookson, 1960, has shorter horns and a clearly delimited parasulcus. D. davidii Morgan, 1975, is of similar size but has a much denser and more accentuated granulate-verrucate ornament, which clearly shows alignment along parasutural boundaries.
Holotype: Burger, 1980, pl.44, fig.3
Age: Aptian
Original diagnosis (Burger, 1980):
Holotype: GSQ Surat 1, depth 305.3 m (100 ft 6 in); Wallumbilla Formation, Doncaster Member; Cretaceous, late Aptian (MFP 5015-1, 282/1117; CPC 16439. Pl. 44, fig. 3).
Description: Cyst biconical, epicyst longer than hypocyst, with a prominent and thin, tubular or tapering horn 8-18 p.m long; hypocyst with a similar but shorter (2-10 p.m) horn. A small intercalary archaeopyle with a triangular to hemispherical outline is formed in a few specimens. A paracingulum is vaguely indicated in several specimens; no other traces of paratabulation are visible. Cyst wall thin, sparsely and to all appearances randomly granulate.
Dimensions: Length (14 specimens) 67-85 µm, width (11 specimens) 40-56 µm.
Distribution: A rare to common species in the Odontochitina operculata Zone.
Comments: The species is a typical representative of Diconodinium. It differs from D. arcticum Manum & Cookson, 1964, in lacking a broad paracingulum and having longer horns. D. glabrum Eisenack & Cookson, 1960, displays a more or less prominent parasulcus and paracingulum. D. inflatum Eisenack & Cookson, 1960, has shorter horns and a clearly delimited parasulcus. D. davidii Morgan, 1975, is of similar size but has a much denser and more accentuated granulate-verrucate ornament, which clearly shows alignment along parasutural boundaries.