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Chaenosphaerula
From Fensome et al., 2019:
Chaenosphaerula, Damassa, 1997, p.167,169.
Type: Damassa, 1997, pl.1, figs.1–2; text-fig.6B, as Chaenosphaerula magnifica.
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Original description: [Damassa, 1997]:
Diagnosis:
Spheroidal cysts, consisting of parasutural framework only, indicating a sexiform gonyaulacoid tabulation. Ventral organization modified S-type; apical-ventral plate contacts variable, li/lu (6"/1') or A/ai (4'/as) for the {A, lu, ai, li} quartet; A/li (4'/6") for the {6, A, ai, li} quartet. Hypocyst torsion neutral. Antapical configuration symmetrical to weakly asymmetrical. Apical and sulcal plates not completely delineated. Archeopyle not present in the usual sense.
Description:
Shape: Spherical when not deformed.
Wall features and relationships: Cysts composed of parasutural framework only; wall (i.e. autophragm or endophragm and periphragm) in the usual sense, not present. Parasutural framework consists of a T-shaped structure: one strip of material is parallel to what would ordinarily be the cyst surface; another is perpendicular and internal to it; in a sense, the inverse of a septal structure which would be found in a typical proximate gonyaulacoid cyst (Plate II, 4-7; Plate III, 1-3).
Archeopyle: Not present in the usual sense, as there is no wall material present except for the parasutural framework.
Tabulation: Sexiform gonyaulacoid tabulation; ventral configuration either A/ai (4'/as) or lu/li (1'/6") for the {A, lu, ai, li} or {4', 1', as, 6"} quartet, and A/li (4'/6") for the {6, A, ai, li} or {5", 4', as, 6"} quartet; sulcus modified S-type. The following plates are present: one small preapical (P), not consistently delineated (Plate I, 9); four apicals (A-C and lu or 1'-4'); six precingulars (2-6 and li or 1" 6"); six cingulars (au, b, c, d, e, fi or lc-6c); six postcingulars (Iu, II-VI or 1'"-6"); a single posterior intercalary (X or lp); a single antapical (Y or 1""); sulcal plates not completely delineated, but anterior sulcal ai (as), posterior sulcal Z (ps) are consistently present. Kofoidian tabulation formula: ?pr, 4', 0a, 6", 6c, 5s, 6", lp, 1".
Cingulum: Six polygonal areas delineated by parasutural material, which may be rectangular to broadly hexagonal.
Sulcus: Anterior sulcal ai (as) and posterior sulcal Z (ps) are consistently present; Kofoidian homologue Iu (1") may be delineated within the sulcal region. Right sulcal Ii (rs) may be delineated in some specimens.
Size: Intermediate, 60-80 μm.
Chaenosphaerula, Damassa, 1997, p.167,169.
Type: Damassa, 1997, pl.1, figs.1–2; text-fig.6B, as Chaenosphaerula magnifica.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Damassa, 1997]:
Diagnosis:
Spheroidal cysts, consisting of parasutural framework only, indicating a sexiform gonyaulacoid tabulation. Ventral organization modified S-type; apical-ventral plate contacts variable, li/lu (6"/1') or A/ai (4'/as) for the {A, lu, ai, li} quartet; A/li (4'/6") for the {6, A, ai, li} quartet. Hypocyst torsion neutral. Antapical configuration symmetrical to weakly asymmetrical. Apical and sulcal plates not completely delineated. Archeopyle not present in the usual sense.
Description:
Shape: Spherical when not deformed.
Wall features and relationships: Cysts composed of parasutural framework only; wall (i.e. autophragm or endophragm and periphragm) in the usual sense, not present. Parasutural framework consists of a T-shaped structure: one strip of material is parallel to what would ordinarily be the cyst surface; another is perpendicular and internal to it; in a sense, the inverse of a septal structure which would be found in a typical proximate gonyaulacoid cyst (Plate II, 4-7; Plate III, 1-3).
Archeopyle: Not present in the usual sense, as there is no wall material present except for the parasutural framework.
Tabulation: Sexiform gonyaulacoid tabulation; ventral configuration either A/ai (4'/as) or lu/li (1'/6") for the {A, lu, ai, li} or {4', 1', as, 6"} quartet, and A/li (4'/6") for the {6, A, ai, li} or {5", 4', as, 6"} quartet; sulcus modified S-type. The following plates are present: one small preapical (P), not consistently delineated (Plate I, 9); four apicals (A-C and lu or 1'-4'); six precingulars (2-6 and li or 1" 6"); six cingulars (au, b, c, d, e, fi or lc-6c); six postcingulars (Iu, II-VI or 1'"-6"); a single posterior intercalary (X or lp); a single antapical (Y or 1""); sulcal plates not completely delineated, but anterior sulcal ai (as), posterior sulcal Z (ps) are consistently present. Kofoidian tabulation formula: ?pr, 4', 0a, 6", 6c, 5s, 6", lp, 1".
Cingulum: Six polygonal areas delineated by parasutural material, which may be rectangular to broadly hexagonal.
Sulcus: Anterior sulcal ai (as) and posterior sulcal Z (ps) are consistently present; Kofoidian homologue Iu (1") may be delineated within the sulcal region. Right sulcal Ii (rs) may be delineated in some specimens.
Size: Intermediate, 60-80 μm.