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Areosphaeridium ebdonii

Areosphaeridium ebdonii, Bujak, 1994, p. 119–121, pl.2, figs.8–9.

Holotype: Bujak, 1994
Paratype: Bujak, 1994
Locus typicus: North Sea, UK16/la-1 Well
Stratum typicum: Lutetian, Middle Eocene

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Original description: [Bujak, 1994]:

Diagnosis:
Cysts skolochorate with subspherical bodies comprising an autophragm.
Body typically with 17 intratabular processes, ten on the epicyst and seven on the hypocyst; areas between process bases smooth, or indistinctly ornamented, or finely and irregularly granulate. Processes less than 15 µm in length. Process stems solid, with proximal fibrous ends expanded slightly and merging smoothly with the autophragm surface. Process stems expanded distally into vasiform or infundibular, fenestrate to reticulate process platforms with irregular to circular outlines. On some specimens the vasiform or infundibular distal terminations have irregular or entire margins. The processes reflect a paratabulation of 4', 6", 0-2c, 5''', 1p, 1'''', 0s, with the hypocystal paratabulation following the standard sexiform pattern.
Paracingulum typically expressed by the absence of processes, but one or two narrow paracingular processes may be present.
Parasulcal processes absent although a medial parasutural notch is frequently discernible.
Archeopyle apical; operculum tetraplacoid, contiguous.

Dimensions:
Central body length (without operculum) 47-53 µm, breadth 40-48 µm, maximum process length 10-12 µm.

Affinities:
A. ebdonii is distinguished from other species of Areosphaeridium by its short processes.

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Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.

Areosphaeridium ebdonii Bujak, 1994, typically has 17 processes, ten on the epicyst. Processes less than 15 µm long and expanded distally into vasiform or infundibular, fenestrate to reticulate process platforms with irregular or circular outline. On some specimens, the vasiform or infundibular distal terminations have irregular or entire margins. Process tabulation 4', 6", 0c, 5"’, 1p,1"”. May have one or two narrow cingular processes. Size: central body length (without operculum) 47-53 µm, width 47-53 µm, maximum process length 10-12 µm.
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