Back
Apteodinium warringtonii
Apteodinium warringtonii, (Poulsen, 1996, p. 69-70, pl.11, figs.1-4; pl.12, figs.1-4), Riding and Fensome, 2003, p.19.
Holotype: Poulsen, 1996, pl.11, figs.1-3.
Recorded occurrences: In the Late? Oxfordian? of the Fjerritslev-2 borehole (1226 m), at the Oxfordian - Kimmeridgian boundary, i.e. Subzone c-d of the Scriniodinium crystallinum Zone of the Haldager-1 borehole (3591 ft.), and in the earliest Volgian (Subzone a of the Glossodinium dimorphum Zone) of the Sound-lA borehole (52 m).
Age: Late Oxfordian?-earliest Volgian.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Poulsen, 1996, p. 69-70]:
Diagnosis:
A proximate cyst having an ornamented surface consisting of an autophragm and a fibrous ectophragm that forms rows and/or a network on the exterior surface. The rows may be pandasutural bands. A hollow apical horn formed by the ectophragm alone.
No or only faint indications of paratabulation, except for the precingular archeopyle, type P3"".
Ectocoel with single or interconnected spines.
Paracingulum indicated by a depression with reduced fibrous ectophragmal network. Parasulcus a narrow, straight, elongate depression.
Description:
An ovoidal to ellipsoidal species of Aldorfia generally with a hollow apical horn formed only from the ectophragm. The wall is an autophragm with an irregular, highly fibrous ectophragm. An ectocoel crossed by interconnected spines separates the autophragm and the ectophragm. The ectophragm and the interconnecting spines may be arranged in rows reflecting pandasutural bands; this feature is best seen under the SEM. The ectophragm may be discontinuous or missing, especially in the central parts of paraplates.
The paratabulation is indicated in varying degrees by the ectophragm as gonyaulacoid L-type.
The archeopyle is precingular, type P3 .
The paracingulum is indicated by a depression with reduced ectophragmal network. The displacement offset (laevorotatory) of the paracingulum is small, about 1 paracingular width. The parasulcus is a long and narrow, straight depression, its paratabulation only visible under the SEM. The size of the cyst is intermediate, length about 50-70 µm; the apical horn is about 6-9 µm. The ectophragmal layer including the interconnected spines is about 3 µm thick.
Dimensions:
18 specimens measured.
Holotype: length 53 µm, width 53 ,um, length of horn 3 µm.
Paratype: length 65 µm, width 46 µm, length of horn 6 µm.
Overall cyst length (minimum-mean-maximum): 52 µm - 58 µm- 66µm.
Overall cyst width (minimum-mean-maximum): 45 µm - 49 µm - 53 µm.
Affinities/Comparison:
Aldorfia warringtonii differs from Aldorfia sp. A of Davey (1982), Aldorfia aldorfensis (Gocht 1970) Stover and Evitt 1978 and Apteodinium spongiosum McIntyre and Brideaux 1980 in having a more open ectophragm and a smaller size. It differs from Aldorfia dictyota (Cookson and Eisenack 1960) Davey 1982 in possessing an irregular fibrous network on the ectophragm.
Holotype: Poulsen, 1996, pl.11, figs.1-3.
Recorded occurrences: In the Late? Oxfordian? of the Fjerritslev-2 borehole (1226 m), at the Oxfordian - Kimmeridgian boundary, i.e. Subzone c-d of the Scriniodinium crystallinum Zone of the Haldager-1 borehole (3591 ft.), and in the earliest Volgian (Subzone a of the Glossodinium dimorphum Zone) of the Sound-lA borehole (52 m).
Age: Late Oxfordian?-earliest Volgian.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Poulsen, 1996, p. 69-70]:
Diagnosis:
A proximate cyst having an ornamented surface consisting of an autophragm and a fibrous ectophragm that forms rows and/or a network on the exterior surface. The rows may be pandasutural bands. A hollow apical horn formed by the ectophragm alone.
No or only faint indications of paratabulation, except for the precingular archeopyle, type P3"".
Ectocoel with single or interconnected spines.
Paracingulum indicated by a depression with reduced fibrous ectophragmal network. Parasulcus a narrow, straight, elongate depression.
Description:
An ovoidal to ellipsoidal species of Aldorfia generally with a hollow apical horn formed only from the ectophragm. The wall is an autophragm with an irregular, highly fibrous ectophragm. An ectocoel crossed by interconnected spines separates the autophragm and the ectophragm. The ectophragm and the interconnecting spines may be arranged in rows reflecting pandasutural bands; this feature is best seen under the SEM. The ectophragm may be discontinuous or missing, especially in the central parts of paraplates.
The paratabulation is indicated in varying degrees by the ectophragm as gonyaulacoid L-type.
The archeopyle is precingular, type P3 .
The paracingulum is indicated by a depression with reduced ectophragmal network. The displacement offset (laevorotatory) of the paracingulum is small, about 1 paracingular width. The parasulcus is a long and narrow, straight depression, its paratabulation only visible under the SEM. The size of the cyst is intermediate, length about 50-70 µm; the apical horn is about 6-9 µm. The ectophragmal layer including the interconnected spines is about 3 µm thick.
Dimensions:
18 specimens measured.
Holotype: length 53 µm, width 53 ,um, length of horn 3 µm.
Paratype: length 65 µm, width 46 µm, length of horn 6 µm.
Overall cyst length (minimum-mean-maximum): 52 µm - 58 µm- 66µm.
Overall cyst width (minimum-mean-maximum): 45 µm - 49 µm - 53 µm.
Affinities/Comparison:
Aldorfia warringtonii differs from Aldorfia sp. A of Davey (1982), Aldorfia aldorfensis (Gocht 1970) Stover and Evitt 1978 and Apteodinium spongiosum McIntyre and Brideaux 1980 in having a more open ectophragm and a smaller size. It differs from Aldorfia dictyota (Cookson and Eisenack 1960) Davey 1982 in possessing an irregular fibrous network on the ectophragm.