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Ovalicysta hiata
From Fensome et al., 2019:
Ovalicysta hiata Bjaerke, 1980, p.71, pl.2, figs.7–12. Holotype: Bjaerke, 1980, pl.2, fig.7; Fensome et al., 1995, fig.1 — p.1543. Taxonomic senior synonym: Dodekovia syzygia, according to Below (1987a, p.121) — however, Lentin and Williams (1989, p.269) retained Ovalicysta hiata. Age: Toarcian.
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Locus typicus: Knorringfjellet, Spitsbergen
Stratum typicum: Toarcian
Original description: Bjaerke 1980, p.71
Diagnosis: Dinoflagellate cyst of the genus Ovalicysta od spherical to ovoidal shape and with a 4-8 µm long apical horn formed mainly by the extension of ectophragm structures. Autophragm thin, less than 1 µm, ectophragm 2-3 µm thick. Ectophragm composed of densely packed, sinuous ridges a few µm long, supporting a continuous outer layer. Outer surface smooth to granular.
Paracingulum seen as a narrow and shallow depression in equatorial position.
Size: 25-45 µm long, 20-29 µm wide (20 specimens).
Remarks: In most of the specimens observed the archaeopyle is clearly formed by the loss of one intercalary paraplate. In a few specimens, however, two more intercalaries are lost, probably because of mechanical damage. Accessory parasutures show that these two intercalaries are also morphologically distinguished. Apart from archaeopyle and accessory parasutures paratabulation is not evident. The outer surface is usually smooth to irregular, sometimes giving a granular appearance.
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Ovalicysta hiata Bjaerke, 1980. Diagnosis from Bjaerke (1980, p.71). Dinoflagellate cysts of the genus Ovalicysta of spherical to ovoidal shape and with 4 to 8 µm long apical horn formed mainly by the extension of ectophragmal structures. Autophragm thin, less than 1 µm, ectophragm2 to 3 µm thick. Ectophragm composed of densely packed, sinuous ridges a few µm long, supporting a continuous outer layer. Outer surface smooth to granular. Paracingulum seen as a narrow and shallow depression in equatorial position.
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Ovalicysta hiata Bjaerke, 1980, p.71, pl.2, figs.7–12. Holotype: Bjaerke, 1980, pl.2, fig.7; Fensome et al., 1995, fig.1 — p.1543. Taxonomic senior synonym: Dodekovia syzygia, according to Below (1987a, p.121) — however, Lentin and Williams (1989, p.269) retained Ovalicysta hiata. Age: Toarcian.
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Locus typicus: Knorringfjellet, Spitsbergen
Stratum typicum: Toarcian
Original description: Bjaerke 1980, p.71
Diagnosis: Dinoflagellate cyst of the genus Ovalicysta od spherical to ovoidal shape and with a 4-8 µm long apical horn formed mainly by the extension of ectophragm structures. Autophragm thin, less than 1 µm, ectophragm 2-3 µm thick. Ectophragm composed of densely packed, sinuous ridges a few µm long, supporting a continuous outer layer. Outer surface smooth to granular.
Paracingulum seen as a narrow and shallow depression in equatorial position.
Size: 25-45 µm long, 20-29 µm wide (20 specimens).
Remarks: In most of the specimens observed the archaeopyle is clearly formed by the loss of one intercalary paraplate. In a few specimens, however, two more intercalaries are lost, probably because of mechanical damage. Accessory parasutures show that these two intercalaries are also morphologically distinguished. Apart from archaeopyle and accessory parasutures paratabulation is not evident. The outer surface is usually smooth to irregular, sometimes giving a granular appearance.
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Ovalicysta hiata Bjaerke, 1980. Diagnosis from Bjaerke (1980, p.71). Dinoflagellate cysts of the genus Ovalicysta of spherical to ovoidal shape and with 4 to 8 µm long apical horn formed mainly by the extension of ectophragmal structures. Autophragm thin, less than 1 µm, ectophragm2 to 3 µm thick. Ectophragm composed of densely packed, sinuous ridges a few µm long, supporting a continuous outer layer. Outer surface smooth to granular. Paracingulum seen as a narrow and shallow depression in equatorial position.
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