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Raphidodinium augustum
Raphidodinium augustum (Harding, 1986) Below, 1987
Now Druggidium. Originally (and now) Druggidium, subsequently Raphidodinium. Lentin and Williams, 1989 retained this species in Druggidium Habib, 1973.
Holotype: Harding 1986, pl.2, fig.1-2
Locus typicus: Otto-Gott brickpit, Germany
Stratum typicum: Hauterivian-Barremian
Original diagnosis: Harding, 1986, p.21: Druggidium augustum
Shape: Ambitus subcircular to ovoid, elongated antero-posteriorly. Greatest width just posterior to the paracingulum. Cyst length unequally divided: hypocyst 2/3 of total, the very wide paracingulum and the epicyst sharing the remaining length equally. Slight dorso-ventral compression (specimens flattened due to postmortem compression within the rock matrix as they show no consistent preferred orientation).
Phragma: Autophragm only, extremely thin (0.1- 0.3 µm thick), strengthened by continuous parasutural ridges (0.4-0.6 mm wide). Sculpture variable, granular.
Granulae may be small and discrete or become fused and merge with the parasutural ridges (especially on the epicyst) and obscure tabulation. Indications of plate-overlap sometimes evident. Circular "ringed pits" may be present on some paraplates (Pl. 2, fig. 4).
Paratabulation: As revised for the genus. Paraplate 4"[A] reduced in length, 7"[1i] no longer in contact with 6c[fi] (see Evitt, 1985, fig. 5. 18C). Epicystal paratabulation often obscured by the sculpture.
Archaeopyle: Variable. Types v. or vi. as listed in the emended generic diagnosis.
Paracingulum: Well developed, very broad, no indentation seen in ambital view.
Parasulcus: Large spatulate sulcal paraplate s[Z], margins convex and narrowing gradually anteriorly. Paraplate rs[Ii] developed but not Is[Im]. Prominent flagellar scar. Dimensions. Length (38) 31.6 (26) µm. Width (35) 28 (24) µm. Width:length ratio (1.10) 0.90 (0.73).
Now Druggidium. Originally (and now) Druggidium, subsequently Raphidodinium. Lentin and Williams, 1989 retained this species in Druggidium Habib, 1973.
Holotype: Harding 1986, pl.2, fig.1-2
Locus typicus: Otto-Gott brickpit, Germany
Stratum typicum: Hauterivian-Barremian
Original diagnosis: Harding, 1986, p.21: Druggidium augustum
Shape: Ambitus subcircular to ovoid, elongated antero-posteriorly. Greatest width just posterior to the paracingulum. Cyst length unequally divided: hypocyst 2/3 of total, the very wide paracingulum and the epicyst sharing the remaining length equally. Slight dorso-ventral compression (specimens flattened due to postmortem compression within the rock matrix as they show no consistent preferred orientation).
Phragma: Autophragm only, extremely thin (0.1- 0.3 µm thick), strengthened by continuous parasutural ridges (0.4-0.6 mm wide). Sculpture variable, granular.
Granulae may be small and discrete or become fused and merge with the parasutural ridges (especially on the epicyst) and obscure tabulation. Indications of plate-overlap sometimes evident. Circular "ringed pits" may be present on some paraplates (Pl. 2, fig. 4).
Paratabulation: As revised for the genus. Paraplate 4"[A] reduced in length, 7"[1i] no longer in contact with 6c[fi] (see Evitt, 1985, fig. 5. 18C). Epicystal paratabulation often obscured by the sculpture.
Archaeopyle: Variable. Types v. or vi. as listed in the emended generic diagnosis.
Paracingulum: Well developed, very broad, no indentation seen in ambital view.
Parasulcus: Large spatulate sulcal paraplate s[Z], margins convex and narrowing gradually anteriorly. Paraplate rs[Ii] developed but not Is[Im]. Prominent flagellar scar. Dimensions. Length (38) 31.6 (26) µm. Width (35) 28 (24) µm. Width:length ratio (1.10) 0.90 (0.73).