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Ochetodinium romanum
Ochteodinium romanum Damassa, 1979
Holotype: Damassa, 1979, pl.6, figs.1,5
Paratypes: Damassa, 1979
Locus typicus: Costal Belt, Franciscan Complex, California, USA
Stratum typicum: Early-Middle Eocene
Original diagnosis: Damassa, 1979, p. 833
Cyst spherical to ellipsoidal paratabulation indicated by highly perforate elevation of autophragm along parasutures. Spinose intratabular ornamentation also developed. Archeopyle margin rounded; operculum may incorporate parts of adjacent paraplates.
Original description: Damassa, 1979, p.833
Spherical to ellipsoidal cyst diameter 44-74 µm (mean = 64 µm of 13 specimens). Paratabulation indicated by highly perforate parasutural elevations of autophragm which are 5-8 µm in height having large openings of variable shape and size but with smooth margins. Thickness of autophragm exclusive of ornamentation 2-3 µm. Intratabular spinose features of ornamentation of about the same height as parasutural ornamentation solid unbranched at tips. These structures are unevenly distributed commonly in groups that are interconnected at bases or toward their distal ends. Surface near parasutures generally with less intratabular ornamentation than central area of paraplate. Paracingulum generally devoid of spinose ornamentation. Archeopyle margin rounded may be enlarged to include part of the paracingulum or adjacent precingular paraplates. Operculum free. Apical paraplates 1 and 4 elongate and narrow of approximately equal size; 2 and 3 also more or less of equal size. Precingular paraplates 1-5 have standard gonyaulacacean shapes; the sixth precingular paraplate is reduced in size but pentagonal in outline. Posterior sulcal and posterior intercalary paraplates are clearly developed but the first postcingular and other sulcal paraplates are small and indistinct. Other postcingular paraplates and the antapical paraplates are standard gonyaulacacean. Paratabulation.--4", 6"", 6c, xs + ps, 1p, 6""", 1"""".
Inferred thecal tabulation.--4", 6"", 6c, 5s, 1p, 6""", 1"""".
Affinities:
Dammassa, 1979, p. 933-834: Ochetodinium romanum shows considerable variation in development of parasutural elevations as well as the intratabular spinose ornamentation. Some instances in which these features are not well developed may result from imperfect preservation rather than original morphologic variability. The archeopyle is also variable in size and shape, generally rounded in outline, and when enlarged may result in the loss of parasutural elevations from adjacent apical, precingular or cingular paraplates (Pl. 6, figs. 1, 2, 4, 6,).
Holotype: Damassa, 1979, pl.6, figs.1,5
Paratypes: Damassa, 1979
Locus typicus: Costal Belt, Franciscan Complex, California, USA
Stratum typicum: Early-Middle Eocene
Original diagnosis: Damassa, 1979, p. 833
Cyst spherical to ellipsoidal paratabulation indicated by highly perforate elevation of autophragm along parasutures. Spinose intratabular ornamentation also developed. Archeopyle margin rounded; operculum may incorporate parts of adjacent paraplates.
Original description: Damassa, 1979, p.833
Spherical to ellipsoidal cyst diameter 44-74 µm (mean = 64 µm of 13 specimens). Paratabulation indicated by highly perforate parasutural elevations of autophragm which are 5-8 µm in height having large openings of variable shape and size but with smooth margins. Thickness of autophragm exclusive of ornamentation 2-3 µm. Intratabular spinose features of ornamentation of about the same height as parasutural ornamentation solid unbranched at tips. These structures are unevenly distributed commonly in groups that are interconnected at bases or toward their distal ends. Surface near parasutures generally with less intratabular ornamentation than central area of paraplate. Paracingulum generally devoid of spinose ornamentation. Archeopyle margin rounded may be enlarged to include part of the paracingulum or adjacent precingular paraplates. Operculum free. Apical paraplates 1 and 4 elongate and narrow of approximately equal size; 2 and 3 also more or less of equal size. Precingular paraplates 1-5 have standard gonyaulacacean shapes; the sixth precingular paraplate is reduced in size but pentagonal in outline. Posterior sulcal and posterior intercalary paraplates are clearly developed but the first postcingular and other sulcal paraplates are small and indistinct. Other postcingular paraplates and the antapical paraplates are standard gonyaulacacean. Paratabulation.--4", 6"", 6c, xs + ps, 1p, 6""", 1"""".
Inferred thecal tabulation.--4", 6"", 6c, 5s, 1p, 6""", 1"""".
Affinities:
Dammassa, 1979, p. 933-834: Ochetodinium romanum shows considerable variation in development of parasutural elevations as well as the intratabular spinose ornamentation. Some instances in which these features are not well developed may result from imperfect preservation rather than original morphologic variability. The archeopyle is also variable in size and shape, generally rounded in outline, and when enlarged may result in the loss of parasutural elevations from adjacent apical, precingular or cingular paraplates (Pl. 6, figs. 1, 2, 4, 6,).