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Sophismatia
From Williams et al., 2017:
[Sophismatia, Williams et al., 2015, p. 312–313.
Type species: as Wetzeliella tenuivirgula, Williams and Downie, 1966b (pl.19, figs.2,4; text-fig.49)]
Stratigraphic occurrence: Early to Middle Eocene (Ypresian–Lutetian), Williams et al., 2015
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Original description [Williams et al., 2015]:
Diagnosis:
Wetzelielloidean cysts with an equiepeliform archeopyle and pericyst with processes that are distally trabeculate.
Description:
Shape: Dorso-ventral outline of pericyst rhomboidal, with variable horn development. Dorso-ventral outline of endocyst ovoidal to quadrate. Horns, other than the right antapical, are generally of the same length.
Wall structure: Periphragm moderately thick, ornamented with penitabular processes or clusters of intratabular processes which are distally connected by trabecula. Endophragm moderately thick, surface smooth to granular, or with features of low relief.
Pericoels: Cysts typically cornucavate.
Tabulation: Delineated by trabecular network, which is supported by penitabular processes and forms simulate complexes.
Archeopyle: Equiepeliform. Perioperculum free. End-operculum of approximately equal size to that of peri-operculum; endoperculum free.
Furrows: Delineated by trabecular network, as above.
Size: Large.
Dimensions:
Williams & Downie (1966) provided the following dimensions for the type material of Wetzeliella (now Sophismatia) tenuivirgula:
overall pericyst length 125–175 μm, pericyst width 120–158 μm, endocyst length 72–113 μm and endocyst breadth 70–104 μm.
For the holotype of Sophismatia crassiramosa, the measurements are overall length 125 μm, overall width 122 μm, endocyst length 80 μm and endocyst width 71 μm.
Discussion:
Sophismatia may be distinguished from other genera having an equiepeliform archeopyle on the basis of its trabeculate processes. Apectodinium and Axiodinium have processes that are distally free. Charlesdowniea has an ectophragm. Epelidinium has a pericyst that is smooth or has features of low relief. Vallodinium has penitabular to sutural ornamentation. Kledodinium, Michouxdinium and Sagenodinium also have trabeculate processes. However, Kledodinium has a latiepeliform archeopyle, Michouxdinium has a soleiform archeopyle and Sagenodinium has a hyperepeliform archeopyle.
[Sophismatia, Williams et al., 2015, p. 312–313.
Type species: as Wetzeliella tenuivirgula, Williams and Downie, 1966b (pl.19, figs.2,4; text-fig.49)]
Stratigraphic occurrence: Early to Middle Eocene (Ypresian–Lutetian), Williams et al., 2015
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description [Williams et al., 2015]:
Diagnosis:
Wetzelielloidean cysts with an equiepeliform archeopyle and pericyst with processes that are distally trabeculate.
Description:
Shape: Dorso-ventral outline of pericyst rhomboidal, with variable horn development. Dorso-ventral outline of endocyst ovoidal to quadrate. Horns, other than the right antapical, are generally of the same length.
Wall structure: Periphragm moderately thick, ornamented with penitabular processes or clusters of intratabular processes which are distally connected by trabecula. Endophragm moderately thick, surface smooth to granular, or with features of low relief.
Pericoels: Cysts typically cornucavate.
Tabulation: Delineated by trabecular network, which is supported by penitabular processes and forms simulate complexes.
Archeopyle: Equiepeliform. Perioperculum free. End-operculum of approximately equal size to that of peri-operculum; endoperculum free.
Furrows: Delineated by trabecular network, as above.
Size: Large.
Dimensions:
Williams & Downie (1966) provided the following dimensions for the type material of Wetzeliella (now Sophismatia) tenuivirgula:
overall pericyst length 125–175 μm, pericyst width 120–158 μm, endocyst length 72–113 μm and endocyst breadth 70–104 μm.
For the holotype of Sophismatia crassiramosa, the measurements are overall length 125 μm, overall width 122 μm, endocyst length 80 μm and endocyst width 71 μm.
Discussion:
Sophismatia may be distinguished from other genera having an equiepeliform archeopyle on the basis of its trabeculate processes. Apectodinium and Axiodinium have processes that are distally free. Charlesdowniea has an ectophragm. Epelidinium has a pericyst that is smooth or has features of low relief. Vallodinium has penitabular to sutural ornamentation. Kledodinium, Michouxdinium and Sagenodinium also have trabeculate processes. However, Kledodinium has a latiepeliform archeopyle, Michouxdinium has a soleiform archeopyle and Sagenodinium has a hyperepeliform archeopyle.