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Pareodinia asperata

Pareodinia asperata Riley in Fisher and Riley, 1980

Holotype: Fisher and Riley, 1980, pl.3, figs.6, 10
Locus typicus: Boulonnais, France
Recorded occurrences: Denmark: Endoscrinium luridum Zone, Perisseiasphaeridium pannosum Subzone - Glossodinium dimorphum Zone, Subzone c; Poland: Autissiodorensis - Tenuicostata Zones.
Stratum typicum: Volgian

Original diagnosis: Riley in Fisher and Riley, 1980, p.324
Proximate cyst elongate to pearshaped, epitract tapering to form a strong, but blunt apical horn of moderate length; antapex rounded. Cyst wall thick, densely granular andlor coarsely tuberculate; occasional tubercules developed into very short, stout, irregularly shaped processes. Archaeopyle intercalary, type lI, hexagonal in shape. No other indication of reflected tabulation, cingulum or sulcus.

Dimensions:
Holotype: overall length 51 µm , breadth 35 µm, length of apical horn 6 µm, height of surface ornamentation up to 1.5 µm. Range: overall length 50-62 µm, breadth 33-35 µm, length of apical horn 5-6 µm.

Affinities:
Riley, 1980, p.324: The combination of overall shape and shape and position of the archaeopyle combine to make this a very distinctive species clearly different from all previously described forms.

Poulsen, 1996, p. 62, Pareodinia asperata Riley 1980 Pl. 4, Fig. 11
Remarks:
The distinction between P. asperata and Gochteodinia mutabilis is based on the difference in archeopyle type, I in the former species and 2I in the latter. The surface ornament is the same for the two species, but G. mutabilis may have an apicular structure and two antapical lobes or protrusions (short antapical horns). However, none of these features are particularly diagnostic for specific distinction within the Pareodinia complex.
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