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Tenua apiculata
From Fensome et al., 2019:
Tenua ?apiculata (Jain and Garg in Jain et al., 1984, p.71–72, pl.2, figs.27–29) Fensome et al., 2019a, p.46.
Holotype: Jain et al., 1984, pl.2, fig.27; Fensome et al., 2019a, fig.17N.
Originally Canningia, subsequently (and now) ?Tenua.
Questionable assignment: Fensome et al. (2019a, p.46).
Age: Kimmeridgian–early Tithonian.
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Original description: [Jain and Garg, 1984, p.71]:
Diagnosis:
Cyst lenticular, autophragm only; processes short, distally truncate to bifid, distantly placed; crest well developed, surface granular; paracingulum faintly indicated; apex pointed, apical horn short; antapex broad. Bilobed.
Archeopyle apical (tA); principal archeopyle suture zig-zag, with six precingular paraplates.
Dimensions:
Holotype Range, Overall cyst size 80x66 µm 66-80x60-70 µm, Process length 4 µm 2-4 µm
Affinitis:
Spiti specimens show mixed characters of Canningia and Aptea. Antapical bilobation puts it closer to Canningia whereas autophragm ornamentation with curved ridges suggest affinity with Aptea. Due to lack of antapical horn, the forms are presently described under Canningia. The present specimens are devoid of any intercalary paraplate. The concept of Dörhöfer and Davies (1980, p. 36) is presently not acceptable.
Tenua ?apiculata (Jain and Garg in Jain et al., 1984, p.71–72, pl.2, figs.27–29) Fensome et al., 2019a, p.46.
Holotype: Jain et al., 1984, pl.2, fig.27; Fensome et al., 2019a, fig.17N.
Originally Canningia, subsequently (and now) ?Tenua.
Questionable assignment: Fensome et al. (2019a, p.46).
Age: Kimmeridgian–early Tithonian.
---------------------------------------------------------------------------------------------------
Original description: [Jain and Garg, 1984, p.71]:
Diagnosis:
Cyst lenticular, autophragm only; processes short, distally truncate to bifid, distantly placed; crest well developed, surface granular; paracingulum faintly indicated; apex pointed, apical horn short; antapex broad. Bilobed.
Archeopyle apical (tA); principal archeopyle suture zig-zag, with six precingular paraplates.
Dimensions:
Holotype Range, Overall cyst size 80x66 µm 66-80x60-70 µm, Process length 4 µm 2-4 µm
Affinitis:
Spiti specimens show mixed characters of Canningia and Aptea. Antapical bilobation puts it closer to Canningia whereas autophragm ornamentation with curved ridges suggest affinity with Aptea. Due to lack of antapical horn, the forms are presently described under Canningia. The present specimens are devoid of any intercalary paraplate. The concept of Dörhöfer and Davies (1980, p. 36) is presently not acceptable.