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Subtilisphaera pirnaensis
From Fensome et al., 2019:
Subtilisphaera pirnaensis (Alberti, 1959b, p.100, pl.8, figs.1,5) Jain and Millepied, 1973, p.27. Holotype: Alberti, 1959b, pl.8, fig.1. Taxonomic senior synonym: Subtilisphaera perlucida, according to Fensome et al., 2009, p.60 — however, Santos et al. (2018, p.168) retained the two species separately. Originally Deflandrea, subsequently Subtilisphaera, thirdly Subtilisphaera? Questionable assignment: Harker and Sarjeant in Harker et al. (1990, p.133) — however, Santos et al. (2018, p.168) considered this species to belong to Subtilisphaera without question. Taxonomic junior synonym: Scriniodinium cooksoniae, according to Sarjeant and Anderson (1969, p.232–233). Lentin and Williams (1976, p.118) stated " 'S. pirnaensis' is transferred to Alterbia ..."; however, they did not effect this change. Age: ?middle Turonian.
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Original description, Alberti, 1959: Deflandrea pirnaensis n. sp. (Taf. 8 Fig. 1-5)
Holotype: The specimen preserved in preparation no. Pi/5/1 and shown in plate 8, fig. 1.
Typical location: Pirna bore (Saxony).
Typical stratum: Middle Turonian.
Diagnosis: Carapace flattened, its outline elongated, approximately pentagonal to almost rhombic. Lateral margins often curved outwards. The epitheca forms an acute-angled triangle and extends into a short apical horn that tapers towards the free end. Hypocleavage smaller than the epitheca. Only one antapical horn present, rarely a second indicated. Transverse groove broad, ±slightly depressed, longitudinal groove questionable. The delicate membrane of the carapace finely granulated. Inner body rounded.
Additions: The antapical horn is oblique to the longitudinal axis of the carapace. The membrane of the carapace is frequently folded, that of the inner body brownish in color. No escape hole could be detected in any of the specimens.
Differential diagnosis: Distinguished from other species of the genus suitable for comparison by its larger epitheca, which forms an acute triangle, the outline of the carapace, and the structure of its membrane.
Dimensions of the holotype: 104 μm, length, 64 μm width. In other specimens, the length varies between 80 μm and 106 μm, the width between 58 μm and 64 μm.
Material: Over 40 specimens
Occurrence: Middle Turonian of the Pirna borehole (Saxony). Zatschke clay (Turonian). Zeichen clay bed (Turonian). Turonian of the Waddekath borehole (Altmark). Coniacian of the Weißwasser-Rietschen borehole (Lusatia).
Subtilisphaera pirnaensis (Alberti, 1959b, p.100, pl.8, figs.1,5) Jain and Millepied, 1973, p.27. Holotype: Alberti, 1959b, pl.8, fig.1. Taxonomic senior synonym: Subtilisphaera perlucida, according to Fensome et al., 2009, p.60 — however, Santos et al. (2018, p.168) retained the two species separately. Originally Deflandrea, subsequently Subtilisphaera, thirdly Subtilisphaera? Questionable assignment: Harker and Sarjeant in Harker et al. (1990, p.133) — however, Santos et al. (2018, p.168) considered this species to belong to Subtilisphaera without question. Taxonomic junior synonym: Scriniodinium cooksoniae, according to Sarjeant and Anderson (1969, p.232–233). Lentin and Williams (1976, p.118) stated " 'S. pirnaensis' is transferred to Alterbia ..."; however, they did not effect this change. Age: ?middle Turonian.
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Original description, Alberti, 1959: Deflandrea pirnaensis n. sp. (Taf. 8 Fig. 1-5)
Holotype: The specimen preserved in preparation no. Pi/5/1 and shown in plate 8, fig. 1.
Typical location: Pirna bore (Saxony).
Typical stratum: Middle Turonian.
Diagnosis: Carapace flattened, its outline elongated, approximately pentagonal to almost rhombic. Lateral margins often curved outwards. The epitheca forms an acute-angled triangle and extends into a short apical horn that tapers towards the free end. Hypocleavage smaller than the epitheca. Only one antapical horn present, rarely a second indicated. Transverse groove broad, ±slightly depressed, longitudinal groove questionable. The delicate membrane of the carapace finely granulated. Inner body rounded.
Additions: The antapical horn is oblique to the longitudinal axis of the carapace. The membrane of the carapace is frequently folded, that of the inner body brownish in color. No escape hole could be detected in any of the specimens.
Differential diagnosis: Distinguished from other species of the genus suitable for comparison by its larger epitheca, which forms an acute triangle, the outline of the carapace, and the structure of its membrane.
Dimensions of the holotype: 104 μm, length, 64 μm width. In other specimens, the length varies between 80 μm and 106 μm, the width between 58 μm and 64 μm.
Material: Over 40 specimens
Occurrence: Middle Turonian of the Pirna borehole (Saxony). Zatschke clay (Turonian). Zeichen clay bed (Turonian). Turonian of the Waddekath borehole (Altmark). Coniacian of the Weißwasser-Rietschen borehole (Lusatia).