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Araneosphaera stephanophora

Arenosphaera stephanophora, (Benedek, 1972); Emendation: Benedek and Sarjeant, 1981

Age: Middle-Late Oligocene.
Holotype: Benedek, 1972, pl.9, fig.6; Benedek and Sarjeant, 1981, fig.10, no.6
Paratype: Benedek and Sarjeant, 1981

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Original description: [Benedek, 1972, p. 30-31]:
missing

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Emended description: [Benedek and Sarjeant, 1982, p. 349-350]:

Diagnosis:
Cyst small, spheroidal to broadly ovoidal, skolochorate.
Processes short (roughly one-third to one half of the shortest cyst cross-measurement), tubular and buccinate, the tips flaring widely: they may bear longitudinal fibres or striae, or may lack such features. The length of the processes is relatively constant over the whole cyst. All, or a variable proportion, of the processes are distally united by a perforate membrane, which may appear fibrous and resembles a clinging, damaged spider"s web.
The surface of the phragma may be psilate or may bear a fine ornamentation.
Paratabulation (as determined from the number and position of the processes) probably 4", 0a, 6", 0c, 5-6" ", 0-1p, 1"""" .
Archaeopyle formed by loss of a single precingular paraplate (Type P).

Dimensions:
Holotype: length 36 µm, breadth 30 µm, length of processes c. 8 µm.
Range of dimensions: Length 30-32 µm, breadth 26-30 µm, length of processes 10-12 µm. Material: 16 specimens.

Affinities:
Araneosphaera stephanophora differs from the only other species of this genus, A. araneosa Eaton 1976 from the English Upper Eocene, in its much smaller size and in having processes of more constant length, with a membrane enveloping the whole cyst instead of one confined essentially to the hypotract.
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