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Areoligera senonensis sensu williams and downie 1966
Areoligera cf. senonensis, Williams and Downie, 1966, pl.25, fig.6
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Original description: [Williams and Downie, 1966, p. 230]:
Description:
One beautifully preserved individual from the London Clay of Sheppey, whilst having the distinctive processes of A. senonensis, also possesses process complexes on the ventral surface. The excellent preservation enabled the tabulation of 6", 5""", 1p, 1"""" to be determined. The six precingulars bear soleate process complexes, four of the postcingulars, 1""", 2""", 4""" and 5""" bear annular complexes. The single antapical protuberance lies immediately beneath the sulcal notch.
A single archaeopyle operculum possessing four annular complexes can also be attributed to A. cf. senonensis. This has an elongate plate 1", with plates 2" and 3" considerably larger than the other two plates.
Dimensions:
Diameter of central body 70 by 85 µm. Length of processes up to 28 µm.
Affinities: (p. 231):
A. cf. senonensis, like A. cf. medusettiformis and A cf. coronata is a form approaching the genus Systematophora. The London Clay forms attributed to Areoligera, differ from Systematophora only because of the presence of process complexes on the central surface, in particular on plate 6"" which is usually barren of processes.
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Original description: [Williams and Downie, 1966, p. 230]:
Description:
One beautifully preserved individual from the London Clay of Sheppey, whilst having the distinctive processes of A. senonensis, also possesses process complexes on the ventral surface. The excellent preservation enabled the tabulation of 6", 5""", 1p, 1"""" to be determined. The six precingulars bear soleate process complexes, four of the postcingulars, 1""", 2""", 4""" and 5""" bear annular complexes. The single antapical protuberance lies immediately beneath the sulcal notch.
A single archaeopyle operculum possessing four annular complexes can also be attributed to A. cf. senonensis. This has an elongate plate 1", with plates 2" and 3" considerably larger than the other two plates.
Dimensions:
Diameter of central body 70 by 85 µm. Length of processes up to 28 µm.
Affinities: (p. 231):
A. cf. senonensis, like A. cf. medusettiformis and A cf. coronata is a form approaching the genus Systematophora. The London Clay forms attributed to Areoligera, differ from Systematophora only because of the presence of process complexes on the central surface, in particular on plate 6"" which is usually barren of processes.