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Phanerodinium ovum
From Fensome et al., 2019:
Phanerodinium ovum Slimani, 1994, p.46–47, pl.7, figs.5–6,33–38. Holotype: Slimani, 1994, pl.7, figs.5–6,33–35. NIA. Age: late Campanian–earliest Danian.
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Original description (Slimani, 1994): Translation PKB 2025:
Phanerodinium ovum sp. nov. (P1.7, fig. 5, 6, 33-38)
Name derivation: Latin: ovum, egg; reference to the ovoid shape of the cyst.
Holiday site: Turnhout -807.90 m, preparation 8, E.F. coord. Z46/2.
Type locality: Turnhout -807.90 m.
Type horizon: Maastrichtian.
Svnonvmie:
?1986:1 Phanerodimum sp. - MARHEINECKE, pl. 7, ftg. 7-8.
?1992: Phanerodinium cayeuxii - MARHEINECKE, pl. 23, fig. 1-2.
Diagnosis: Small proximal, acavate, ovoid cyst. The epicyst is approximately hemispheroidal and about four laws smaller than the hypocyst. The hypocyst is hemiovoidal with a maximum width in its anterior part. Low parasutural ridges with short gonal processes indicate a paratabulation that is expressed only on the dorsal surface; the ventral surface is devoid of it. The paratabulation conforms to the following formula: 7', 3"- 7/6". 3c - ?6c, 3"'- 7/6"", 1"". The archaeopyle is precingulate of type P (73"), the operculum is free.
Dimensions:
Holotype: Maximum diameter: 20 µm.
Variations: Maximum diameter: 16-26 µm.
Number of specimens measured: 10.
Material; > 20 specimens.
Description: The cyst is often flattened dorsoventrally. The autophragm is smooth to slightly scabrous. The parasutural ridges are slightly microperforated with weakly serrate and dense thickenings at their base, and a straight to slightly wavy distal margin. The gonal processes (2 µm long in the holotype) are present only at the ridge junctions; they are acuminate or slightly capitate, and consist of strong axes that support the ridges. The paracingulate processes are sometimes connected distally, forming two small lateral arches. The dorsal surface of the cyst is occupied by three triangular precingulate paraplates, two rectangular precingulate paraplates, three trapezoidal postcingulate paraplates, and one pentagonal antapical paraplate; the posterior intercalary paraplate is absent. The paracingulum is apparently non-spiral. The archaeopyle is triangular and medial in position on the dorsal surface of the cyst.
Note: Phanerodinùm ovum sp. nov. is distinguished from Phanerodinium cayeuxii (DEFLANDRE, 1935) DEFLANDRE ( 1937a) by the ovoid shape of its cyst, by its microperforated ridges with a straight to slightly undulating distal margin and especially by the absence of the posterior intercalary paraplate and the presence of only three postcingulate paraplates. In accordance with the specimens of the original material figured by Deflandre, Ph. cayeuxii has a polyhedral hypocyst which presents four postcingulate paraplates and one posterior intercalary paraplate. Some of the specimens from the Coniacian of Pas-de-Calais (France) named Ph. cayeuxii by FOUCHER (1971 b: p. 108, pl. 10, fig. 17-18) also have parasutural crests which are weakly undulated but differ from the species studied mainly by the presence of the posterior intercalary paraplate and probably 4 postcingulate paraplates which are discernible on the figures. Ph. ovum sp. nov. is probably comparable to the specimens from the Maastrichtian of Hemmoor (Germany), which are recently attributed to Ph. cayeuxii by MARHEINECKE (see synonymy above).
Stratigraphic distribution: Halembaye: sample. 25 to 57, upper Campanian. - Maastrichtian upper. (B. mucronata zone - B. junior zone). Turnhout: -932 to -759.89 m, Maastrichtian inf. - late late Maastrichtian, early Danian. MARHEINECK E (1992), Maastrichtian, Hemmoor, Germany.
Phanerodinium ovum Slimani, 1994, p.46–47, pl.7, figs.5–6,33–38. Holotype: Slimani, 1994, pl.7, figs.5–6,33–35. NIA. Age: late Campanian–earliest Danian.
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Original description (Slimani, 1994): Translation PKB 2025:
Phanerodinium ovum sp. nov. (P1.7, fig. 5, 6, 33-38)
Name derivation: Latin: ovum, egg; reference to the ovoid shape of the cyst.
Holiday site: Turnhout -807.90 m, preparation 8, E.F. coord. Z46/2.
Type locality: Turnhout -807.90 m.
Type horizon: Maastrichtian.
Svnonvmie:
?1986:1 Phanerodimum sp. - MARHEINECKE, pl. 7, ftg. 7-8.
?1992: Phanerodinium cayeuxii - MARHEINECKE, pl. 23, fig. 1-2.
Diagnosis: Small proximal, acavate, ovoid cyst. The epicyst is approximately hemispheroidal and about four laws smaller than the hypocyst. The hypocyst is hemiovoidal with a maximum width in its anterior part. Low parasutural ridges with short gonal processes indicate a paratabulation that is expressed only on the dorsal surface; the ventral surface is devoid of it. The paratabulation conforms to the following formula: 7', 3"- 7/6". 3c - ?6c, 3"'- 7/6"", 1"". The archaeopyle is precingulate of type P (73"), the operculum is free.
Dimensions:
Holotype: Maximum diameter: 20 µm.
Variations: Maximum diameter: 16-26 µm.
Number of specimens measured: 10.
Material; > 20 specimens.
Description: The cyst is often flattened dorsoventrally. The autophragm is smooth to slightly scabrous. The parasutural ridges are slightly microperforated with weakly serrate and dense thickenings at their base, and a straight to slightly wavy distal margin. The gonal processes (2 µm long in the holotype) are present only at the ridge junctions; they are acuminate or slightly capitate, and consist of strong axes that support the ridges. The paracingulate processes are sometimes connected distally, forming two small lateral arches. The dorsal surface of the cyst is occupied by three triangular precingulate paraplates, two rectangular precingulate paraplates, three trapezoidal postcingulate paraplates, and one pentagonal antapical paraplate; the posterior intercalary paraplate is absent. The paracingulum is apparently non-spiral. The archaeopyle is triangular and medial in position on the dorsal surface of the cyst.
Note: Phanerodinùm ovum sp. nov. is distinguished from Phanerodinium cayeuxii (DEFLANDRE, 1935) DEFLANDRE ( 1937a) by the ovoid shape of its cyst, by its microperforated ridges with a straight to slightly undulating distal margin and especially by the absence of the posterior intercalary paraplate and the presence of only three postcingulate paraplates. In accordance with the specimens of the original material figured by Deflandre, Ph. cayeuxii has a polyhedral hypocyst which presents four postcingulate paraplates and one posterior intercalary paraplate. Some of the specimens from the Coniacian of Pas-de-Calais (France) named Ph. cayeuxii by FOUCHER (1971 b: p. 108, pl. 10, fig. 17-18) also have parasutural crests which are weakly undulated but differ from the species studied mainly by the presence of the posterior intercalary paraplate and probably 4 postcingulate paraplates which are discernible on the figures. Ph. ovum sp. nov. is probably comparable to the specimens from the Maastrichtian of Hemmoor (Germany), which are recently attributed to Ph. cayeuxii by MARHEINECKE (see synonymy above).
Stratigraphic distribution: Halembaye: sample. 25 to 57, upper Campanian. - Maastrichtian upper. (B. mucronata zone - B. junior zone). Turnhout: -932 to -759.89 m, Maastrichtian inf. - late late Maastrichtian, early Danian. MARHEINECK E (1992), Maastrichtian, Hemmoor, Germany.