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Wilsonisphaera
From Williams et al., 2017:
[Wilsonisphaera, Slimani, 1994, p. 67-68
Type species: originally as Thalassiphora? petila, Corradini, 1973 (pl.31, fig.2)] ; Wilsonisphaera petila, Slimani, 1994
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Original description: [Slimani, 1994]: (Translation: LPP):
Diagnosis:
Proximate, cavate cyst with a subcircular outline in dorsoventral view. A large, dorsally open, subspheroidal pericyst and a small central ovoidal to ellipsoidal endocyst are separated by a large pericoel, and connected in the posterior sulcal area by means of a large membranous, funnel-shaped process.
The endophragm and periphragm are smooth to scabrate, the surface of the periphragm is subdivided by low parasutural crests which indicate a complete or partial paratabulation. The archaeopyle is precingular type P (3`` only) with a small endoarchaeopyle with an attached or free operculum, and a large periarchaeopyle with a free operculum. The paratabulation is gonyaulacoid and corresponds to the formula: 4`, 5-6``, 5-6c, 5-6```, 1p, 1````. The paracingulum is indicated by by 5 to 6 rectangular paraplates. The parasulcus stretches from the apex to the antapex. The size is intermediate to large, 60 to 110 µm.
Affinities:
This genus is characterized by its large cyst with the endophragm and periphragm separated by a large pericoel and interconnected ventrally by a posterior sulcal membranous process. The periphragm and endophragm in Amiculosphaera Harland, 1979, are also separated by a pericoel, but are in contact on the antapical surface and interconnected by means of an apical process. Invertocysta Edwards, 1984, and Turnhosphaera Slimani, 1994, have a close resemblance with Wilsonisphaera, especially in the presence of a type P(3``) precingular archaeopyle with a small endoarchaeopyle and a large periarchaeopyle; but they differ respectively in a circumcavate cyst with an endophragm and periphragm which are in contact midventrally, and an epicavate cyst. Thalassiphora Eisenack and Gocht, 1960 emend. Gocht, 1968 emend. Benedek and Gocht, 1981 and Disphaeria Cookson and Eisenack, 1960 emend. Norvick, 1973 emend. Norvick, 1976 have a periphragm which is ventrally open and middorsally in contact with the endophragm. Stephodinium Deflandre, 1936 emend. Davey, 1970 has an equatorial pericoel.
[Wilsonisphaera, Slimani, 1994, p. 67-68
Type species: originally as Thalassiphora? petila, Corradini, 1973 (pl.31, fig.2)] ; Wilsonisphaera petila, Slimani, 1994
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Slimani, 1994]: (Translation: LPP):
Diagnosis:
Proximate, cavate cyst with a subcircular outline in dorsoventral view. A large, dorsally open, subspheroidal pericyst and a small central ovoidal to ellipsoidal endocyst are separated by a large pericoel, and connected in the posterior sulcal area by means of a large membranous, funnel-shaped process.
The endophragm and periphragm are smooth to scabrate, the surface of the periphragm is subdivided by low parasutural crests which indicate a complete or partial paratabulation. The archaeopyle is precingular type P (3`` only) with a small endoarchaeopyle with an attached or free operculum, and a large periarchaeopyle with a free operculum. The paratabulation is gonyaulacoid and corresponds to the formula: 4`, 5-6``, 5-6c, 5-6```, 1p, 1````. The paracingulum is indicated by by 5 to 6 rectangular paraplates. The parasulcus stretches from the apex to the antapex. The size is intermediate to large, 60 to 110 µm.
Affinities:
This genus is characterized by its large cyst with the endophragm and periphragm separated by a large pericoel and interconnected ventrally by a posterior sulcal membranous process. The periphragm and endophragm in Amiculosphaera Harland, 1979, are also separated by a pericoel, but are in contact on the antapical surface and interconnected by means of an apical process. Invertocysta Edwards, 1984, and Turnhosphaera Slimani, 1994, have a close resemblance with Wilsonisphaera, especially in the presence of a type P(3``) precingular archaeopyle with a small endoarchaeopyle and a large periarchaeopyle; but they differ respectively in a circumcavate cyst with an endophragm and periphragm which are in contact midventrally, and an epicavate cyst. Thalassiphora Eisenack and Gocht, 1960 emend. Gocht, 1968 emend. Benedek and Gocht, 1981 and Disphaeria Cookson and Eisenack, 1960 emend. Norvick, 1973 emend. Norvick, 1976 have a periphragm which is ventrally open and middorsally in contact with the endophragm. Stephodinium Deflandre, 1936 emend. Davey, 1970 has an equatorial pericoel.