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Palaeocystodinium punctatum

Palaeocystodinium punctatum Jain and Millepied, 1973, p.29, pl.2, fig.24 (identified as Palaeocystodinium microgranulatum in the figure caption); pl.3, figs.26–28. Emendation: Masure et al., 1996, p.180–181, as Andalusiella mauthei subsp. punctata.

NOW Andalusiella mauthei subsp. punctata. Originally Palaeocystodinium punctatum, subsequently Andalusiella polymorpha subsp. punctata, thirdly (and now) Andalusiella mauthei subsp. punctata.
Taxonomic senior synonym (at specific rank): Svalbardella (as Alterbia; now Andalusiella) polymorpha, according to Lentin and Williams (1976, p.89) — however, Schrank (1987, p.265) retained Palaeocystodinium punctatum (as Andalusiella polymorpha subsp. punctata).

Holotype: Jain and Millepied, pl.3, fig.27
Age: Maastrichtian
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Original diagnosis: Jain and Millepied 1973, p. 29:
Shell spindle-shaped, dorso-ventrally flattened, with two short appendages, one apical and one antapical; Antapical horn divided into a another short horn. Archeopyle trapezoidal below apical horn; periphragm micropunctate. Capsule large, filling completely periphragm cavity, endophragm smooth. Apical horn terminate into a dentate end on free side. No furrows seen. Archeopyle not observed in all specimens. Another thin membrane exterior to periphragm is present, seen only around horns. The size ratio between horn and central vesicle (H-V ratio) remains mostly 1:4.

Dimensions:
Holotype: Shell length 144µm, breadth 65µm; Capsule length 91µm, breadth 65µm; Apical horn-length 22.1µm, breadth 9.1µm; Antapical horns-length 31.2µm, breadth 7.8µm.
Observed range: Shell length 140-150µm, breadth 55-70µm; Capsule length 95-97µm, breadth 60-70µm; Apical horn-length 22-23µm, breadth 8-11µm; Antapical horns-length 9-32µm, breadth 4-8µm.

Comparison: Palaeocystodinium punctatum sp. nov. compares only with P. benjaminii Drugg (1967) in having two antapical horns but differs readily in having no fiber or hairs on the apical horn and having dentate apex, micropunctate periphragm and third exterior layer.

Remarks: The presence of two closely placed antapical horns and horn-vesicle ratio makes it difficult to place this species in Palaeocystodinium and the former evidence might permit the transfer of these forms under a new genus.
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