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Phanerodinium septatum
From Fensome et al., 2019:
Phanerodinium septatum Slimani, 1994, p.47–48, pl.7, figs.13–14,39–43. Holotype: Slimani, 1994, pl.7, figs.13–14,39–41. Age: late Campanian–late Maastrichtian.
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Original description (Slimani, 1994): Translation PKB 2025:
Phanerodinium septatum sp. nov. (P1.7, Fig. 13, 14, 39-43)
Name derivation: From parasutural septa.
Holotype: Turnhout -933 m, preparation 3, E.F. coord. S32/1.
Type locality: Turnhout -933 m.
Type horizon: Campanian.
Diagnosis: Small, proximochorate, acavate, polyhedral cyst with a subovoidal to subspheroidal central body. The epicyst is about four times smaller than the hypocyst, which is prismatic and wider, with a maximum width at the posterior margin of the paracingulate. The dorsal surface has a paratabulaiion indicated by high parasutural septa supported by gonal axes, while the ventral surface lacks one. The paratabulaiion conforms to the following formula: ?', 3" - ?6", 3c - ?6c, 3"'- ?6"', lp, 1"". The archaeopyle is precingulate of type P (?3"), the operculum is free.
Dimensions:
Holotype: central body, length: 18 µm, width: 14 µm; entire cyst, length: 24 µm, width: 24 µm.
Variations: central body; length: 16-22 µm, width: 12-18 µm; entire cyst: length: 20-30 µm, width: 18-30 µm.
Number of specimens measured: 7.
Material: 8 specimens.
Description: The cyst is dorsoventrally flattened. The autophragm is smooth to finely punctate. The parasutural septa are also smooth to punctate and tall relative to the cyst size (up to 4 µm in height); the gonal axes that support them are located at their junctions; they are solid, inserted proximally on the central body, and reach a length of 4 to 12 µm. The septa extend distally around these axes, forming short, protruding processes that are acuminate to slightly capitate. The paratabulaiion is expressed dorsally by 3 subtriangular precingulate paraplates, 3 rectangular paracingulate paraplates, a pentagonal antapical paraplate, a quadrangular posterior intercalary paraplate and 3 postcingulate paraplates of which the middle one is pentagonal and the other two trapezoidal. The paracingulum (up to 4 µm wide) is weakly laevogyrous. The median archaeopyle is subtriangular.
Note: Phanerodinium septatum sp. nov. is characterized by the presence of high parasutural septa, supported by long gonal axes; it therefore differs from Phanerodinium ovum sp. nov. which, on the contrary, has low micropyrrulated ridges and which lacks the posterior intercalary plate. Ph. cayeuxii (DEFLANDRE, 1935) DEFLANDRE (1937a) has low and warty ridges and presents 4 postcingulate paraplates instead of 3. Mirrodinium ?horridum (BELOW, 1987b) LENTIN and WILLIAMS (1989) has a form comparable to that of the studied species but, given its complete paratabulaiion and its apical and intercalary archaeopyle, it belongs rather to the Mirrodinium complex than to that of Phanerodinium (Evitt, 1985: p. 216).
Stratigraphic distribution: Turnhout: -933 to -775.01 m, Upper Campanian - Late Upper Maastrichtian.
Phanerodinium septatum Slimani, 1994, p.47–48, pl.7, figs.13–14,39–43. Holotype: Slimani, 1994, pl.7, figs.13–14,39–41. Age: late Campanian–late Maastrichtian.
---------------------------------------------------------------------------------------------------
Original description (Slimani, 1994): Translation PKB 2025:
Phanerodinium septatum sp. nov. (P1.7, Fig. 13, 14, 39-43)
Name derivation: From parasutural septa.
Holotype: Turnhout -933 m, preparation 3, E.F. coord. S32/1.
Type locality: Turnhout -933 m.
Type horizon: Campanian.
Diagnosis: Small, proximochorate, acavate, polyhedral cyst with a subovoidal to subspheroidal central body. The epicyst is about four times smaller than the hypocyst, which is prismatic and wider, with a maximum width at the posterior margin of the paracingulate. The dorsal surface has a paratabulaiion indicated by high parasutural septa supported by gonal axes, while the ventral surface lacks one. The paratabulaiion conforms to the following formula: ?', 3" - ?6", 3c - ?6c, 3"'- ?6"', lp, 1"". The archaeopyle is precingulate of type P (?3"), the operculum is free.
Dimensions:
Holotype: central body, length: 18 µm, width: 14 µm; entire cyst, length: 24 µm, width: 24 µm.
Variations: central body; length: 16-22 µm, width: 12-18 µm; entire cyst: length: 20-30 µm, width: 18-30 µm.
Number of specimens measured: 7.
Material: 8 specimens.
Description: The cyst is dorsoventrally flattened. The autophragm is smooth to finely punctate. The parasutural septa are also smooth to punctate and tall relative to the cyst size (up to 4 µm in height); the gonal axes that support them are located at their junctions; they are solid, inserted proximally on the central body, and reach a length of 4 to 12 µm. The septa extend distally around these axes, forming short, protruding processes that are acuminate to slightly capitate. The paratabulaiion is expressed dorsally by 3 subtriangular precingulate paraplates, 3 rectangular paracingulate paraplates, a pentagonal antapical paraplate, a quadrangular posterior intercalary paraplate and 3 postcingulate paraplates of which the middle one is pentagonal and the other two trapezoidal. The paracingulum (up to 4 µm wide) is weakly laevogyrous. The median archaeopyle is subtriangular.
Note: Phanerodinium septatum sp. nov. is characterized by the presence of high parasutural septa, supported by long gonal axes; it therefore differs from Phanerodinium ovum sp. nov. which, on the contrary, has low micropyrrulated ridges and which lacks the posterior intercalary plate. Ph. cayeuxii (DEFLANDRE, 1935) DEFLANDRE (1937a) has low and warty ridges and presents 4 postcingulate paraplates instead of 3. Mirrodinium ?horridum (BELOW, 1987b) LENTIN and WILLIAMS (1989) has a form comparable to that of the studied species but, given its complete paratabulaiion and its apical and intercalary archaeopyle, it belongs rather to the Mirrodinium complex than to that of Phanerodinium (Evitt, 1985: p. 216).
Stratigraphic distribution: Turnhout: -933 to -775.01 m, Upper Campanian - Late Upper Maastrichtian.