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Thalassiphora pansa
Thalassiphora? pansa Stover, 1977
Now Saturnodinium. Originally Thalassiphora?, subsequently (and now) Saturnodinium. Stover, 1977 questionably included this species in Thalassiphora.
Holotype: Stover, 1977, pl.2, figs.34-36
Locus typicus: Corehole 5/5B, Blake Plateau, Western N Atlantic
Stratum typicum: Middle Oligocene
Original description: Stover, 1977, p. 78
Cysts are cavate, compressed equatorially, and the outline of the pericyst is subcircular, generally with shallow concavities. Endocyst is subspherical, but its shape is almost allways modified by folding. Endophragm is thin and smooth; periphragm is also thin, smooth or faintly ornamented and may have faint parasutural lines. Periphragm appressed to endophragm dorsally and separated elsewhere with the resulting pericoel being exceptionally wide ventrally. Archeopyle is precingular, type P, formed by release of paraplate 3"" only, and the operculumis free. Paratabulation indicated mainly by archeopyle and paracingulum; parasutural features are discontinuous and occur inconsistently. Paracingulum indicated marginally by 5 to 10 linear groups of denticles or short spines separated by generally shallow concavities. Linear groups may be single or inapical-antapical pairs (one above the other), and groups on the dorsal surface are more commonly paired than the others. Width of linear groups is 8 to 30 Ám, and the number of projections in each group varies from 2 to 10 and is usually 5. A large midventral paracingular pore-like opening occurs in the periphragm. Parasulcus is not expressed. Overall size in apical-antapical view is 64 by 66 Ám to 82 by 84 Ám; endocystdiameter 38 to 50 Ám.
Affinities: Stover, 1977, p. 78-79
The unique characteristics of Thalassiphora? pansa are its preferred apical-antapical flattening, the presence of paracingular linear groups of denticles or short spines on the periphragm and the paracingular pore-like feature in the midventral area. Among species of Thalassiphora, T. delicata Williams and Downie in Davey et al., 1966 emend. Eaton, 1976 appearsmost similar to T. ? pansa; it differs from T. ? pansa by having low parasutural ridges, a much larger ventral opening that is not confined to the paracingulum and by lacking the groups of denticles or short spines along the paracingulum. The new species is placed in Thalassiphora with reservation because of its apical-antapical flattening - a condition not associated with the current concept of the genus.
Now Saturnodinium. Originally Thalassiphora?, subsequently (and now) Saturnodinium. Stover, 1977 questionably included this species in Thalassiphora.
Holotype: Stover, 1977, pl.2, figs.34-36
Locus typicus: Corehole 5/5B, Blake Plateau, Western N Atlantic
Stratum typicum: Middle Oligocene
Original description: Stover, 1977, p. 78
Cysts are cavate, compressed equatorially, and the outline of the pericyst is subcircular, generally with shallow concavities. Endocyst is subspherical, but its shape is almost allways modified by folding. Endophragm is thin and smooth; periphragm is also thin, smooth or faintly ornamented and may have faint parasutural lines. Periphragm appressed to endophragm dorsally and separated elsewhere with the resulting pericoel being exceptionally wide ventrally. Archeopyle is precingular, type P, formed by release of paraplate 3"" only, and the operculumis free. Paratabulation indicated mainly by archeopyle and paracingulum; parasutural features are discontinuous and occur inconsistently. Paracingulum indicated marginally by 5 to 10 linear groups of denticles or short spines separated by generally shallow concavities. Linear groups may be single or inapical-antapical pairs (one above the other), and groups on the dorsal surface are more commonly paired than the others. Width of linear groups is 8 to 30 Ám, and the number of projections in each group varies from 2 to 10 and is usually 5. A large midventral paracingular pore-like opening occurs in the periphragm. Parasulcus is not expressed. Overall size in apical-antapical view is 64 by 66 Ám to 82 by 84 Ám; endocystdiameter 38 to 50 Ám.
Affinities: Stover, 1977, p. 78-79
The unique characteristics of Thalassiphora? pansa are its preferred apical-antapical flattening, the presence of paracingular linear groups of denticles or short spines on the periphragm and the paracingular pore-like feature in the midventral area. Among species of Thalassiphora, T. delicata Williams and Downie in Davey et al., 1966 emend. Eaton, 1976 appearsmost similar to T. ? pansa; it differs from T. ? pansa by having low parasutural ridges, a much larger ventral opening that is not confined to the paracingulum and by lacking the groups of denticles or short spines along the paracingulum. The new species is placed in Thalassiphora with reservation because of its apical-antapical flattening - a condition not associated with the current concept of the genus.