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Glaphyrocysta undulata

Glaphyrocysta? undulata (Eaton, 1976) Stover and Evitt, 1978

Now Areoligera. Originally (and now) Areoligera, subsequently Glaphyrocysta?.
Jain and Garg, 1986, retained this species in Areoligera Lejeune-Carpentier, 1938.
Stover and Evitt, 1978, considered this to be a provisionally accepted species of Glaphyrocysta.

Holotype: Eaton, 1976, pl.4, figs.4,6; text-fig.9; Bujak et al., 1980, pl.9, figs.7–8; Fauconnier and Masure, 2004, pl.5, figs.1–3.
Locus typicus: Alum Bay, Isle of Wight, England
Stratum typicum: Middle-Late Eocene

Original diagnosis: Eaton, 1976, p. 248: Areoligera undulata
Cyst body dorsoventrally flattened with a smooth of finely granular surface. The circular or subcircular outline may be modified by the development of one or two antapical protuberances. Ventral and dorsal surfaces bear sail-like membranes with lobate undulating distal margins. Ventral membrane restricted to the peripheral zone, aligned parallel to, and situated close to, the margin of the cyst body. Dorsal membranes organized into process complexes which may be arcuate, soleate or annular on the pre- and postcingular zones, linear on the cingular zone, and annular on the antapical zone. Archaeopyle apical, tetratabular.
Dimensions: Holotype: cyst body (without operculum) 56x82 Ám; height of membrane up to 30 Ám. Observed range: cyst body (without operculum) 52x54 Ám to 73x92 Ám; (complete) 66x68 Ám to 75x75 Ám; height of membrane up to 32 Ám. (n = 25).

Affinities:
Eaton, 1976,p. 248: Areoligera undulata
A specimen assignable to Areoligera undulata was recorded from the Upper Eocene of East Prussia by Eisenack (1954), described in the text as Palmnickia sp. indet., and on the plate explanation as Palmnickia sp. ex aff. Iobifera (Eisenack 1954: 70; pl. I2, fig. 20). Evitt (1961: 400; pl. 8, figs 16--17; pl. 9, figs 8-10) illustrated and described the specimen recorded by Eisenack, and commented on its affinities with the genus Areoligera, noting in particular the overall shape and the distribution of the processes.
The textural appearance of the membranes, and the variation in the type of process complex developed on the dorsal surface in A. undulata, are similar to those of A. sentosa n. sp. A few specimens have been recorded in which all the pre- and postcingular complexes are annular, while in some forms they are all arcuate. No forms have been recorded with process complexes developed on the ventral surface, although in one specimen there is some loss of proximal continuity in the membrane on the ventral surface. The undulating nature of the distal margin of the sail-like membranes and the absence of distal spines distinguish A. undulata from A. sentosa and A. tauloma.
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