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Cirrusphaera dissimilis

Cirrusphaera dissimilis, Monteil, 1992

Holotype: Monteil, 1992a, pl.2, figs.1-9; Fauconnier and Masure, 2004, pl.16, figs.1-3.
Locus typicus: Berrias section, Ardèche, SE France
Stratum typicum: Middle-Late Berriasian, occitanica Zone, dalmasi Subzone, zone C

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Original description: [Monteil, 1992, p. 277]: (Translation: LPP): (identical to that of the genus):

Diagnosis:
Synopsis: Cyst chorate, acavate, subspherical.
Processes organised in annular complexes, distally connected by a ring-trabeculum. Presence of trabecular connections between complexes. Paracingular processes typically connected by an equatorial trabeculum.
Paratabulation probably of gonyaulacoid type.
Archaeopyle apical, type (tA). Opercular piece free.

Diagnosis:
Shape: Cyst chorate, acavate, subspherical.
Wall structure: Autophragm only.
Wall characteristics: penitabular processes organised in complexes, rising from annular or straight septa. complex formed by about ten processes distally inteconnected by trabeculae. Presence of trabecular interconnections between the complexes. Surface between processes smooth to granulate.
Archaeopyle: Apical, type (tA). Opercular piece free.
Paratabulation: Indicated by the archaeopyle margin and the process complexes. Formula not yet elucidated, but probably of gonyaulacoid type.
Paracingulum: Indicated by an transverse alignment of processes. Paracingular processes interconnected by an equatorial trabeculum, isolated or rarely connected with the complexes of the precingular and postcingular series.
Parasulcus: not observed.
Size: small, 45-50 µm wide.

Dimensions:
Holotype: cyst length x width = 43 x 50 µm; length x width of central body = 30 x 34 µm; process length = 7-9 µm.
Specimen 1 (slightly oblique): cyst length = 44 µm; central body width = 30 µm; process length = 6-8 µm.
Variation (8 specimens): central body (sic, should be "overall") width = 42-50 µm; central body width = 30-36 µm; process length 6-9 µm.

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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.

Cirrusphaera dissimilis Monteil, 1992a, is a chorate, acavate, subspherical cyst. The processes, which have a proximal bulge, are organized into annulate complexes which are united distally by a ring of trabeculae. There are also trabecular connections between complexes. The paracingular processes are typically united by a an equatorial trabecula. Tabulation probably gonyaulacoid. Archeopyle apical with free operculum.
Size: length 42 x 50 to 30 x 36 µm. Processes 6-9 µm.
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