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Evansia cerebraloides

Evansia cerebraloides (Århus et al., 1989, p.45, figs.4a-d) Lentin and Williams, 1993, p.214.

Holotype: Århus et al., 1989, fig.4a. Originally Glomodinium, subsequently (and now) Evansia.
Age: late Mid-early Late Callovian.

Original description (Arhus et al., 1989)
Glomodinium cerebraloides n. sp.Fig. 4a-d
Holotype: Core 3, 17.00 m, slide l, England Finder reference B27 /3, fig. 4a; Callovian.
Paratypes: Nine specimens from core 3 offshore Helgeland, Norway. Callovian.
Occurrence: One to three specimens per slide are found at 23.55, 21.32, 17.00, 15.50, 12.40, and 8.16 m in core 3 (late Middle-early Late Callovian) to the west of Vega, Helgeland, Norway (65°38.4'N ,10°59.2'E).

Description: Proximate cysts with ovoidal main body and stout tapering bl unt horns 5-121-Lm long. Overall dimensions 56-65 x 33-43!J.m. Wall 1-3 µm thick, inner layer dense, outer layer thicker than inner, very characteristically rugate, slightly thickened around tip of apical horn; archeopyle intercalary, type 31. Some or all of the three hexagonal opercular pieces often occur in place. If lost, this weakens the cysts so much that they may break off at the ventral side and apparentlyhave apical archeopyles. No paraplate pattern determined except in the intercalary series.

Remarks: This species is easily recognized on the basis of its characteristic rugate wall ornament.Measured overall dimensions in µm: 65 x 43, 65X41, 62 x 33, 60 x 37, 59 x 40, 56 x 41, 56 X 33.
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