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Chlamydophorella ovulum
From Fensome et al., 2019:
Chlamydophorella ovulum Wheeler and Sarjeant, 1990, p.315–316, pl.12, figs.4–6; text-figs.12a–b ex Wheeler and Sarjeant, 1992, p.381. Holotype: Wheeler and Sarjeant, 1990, pl.12, fig.4. This name was not validly published in Wheeler and Sarjeant (1990), since the lodgement of the holotype was not specified (ICN Article 40.7). NIA. Age: late Callovian–early Oxfordian.
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Original description: [Wheeler and Sarjeant, 1990]:
Chlamydophorella ovulum sp. nov.
Holotype: G. Mus. Pd. 143; 129.8/17.8 Plate 12 fig. 4].
Paratype: G. Mus. Pd. 144; 114.6/20.8 Plate 12 figs. 5-6].
Derivation of name: L. ovulum, diminutive of egg. From the ovoid ambitus.
Diagnosis: Cyst proximate, holocavate and cryptotabulate. Autophragm covered by numerous (c. 200) nontabular processes, which are in turn typically enclosed by a thin ectophragm. Processes short (1/10th cyst length) and of variable diameter, hollow and consistently buccinate in lateral view, the distal terminations being osculate. Often there is a distinctive short, wide subconical process near the antapex.
Archaeopyle apical, Type tA; operculum free.
Material: Sixty-five specimens from samples 1265, 1266 and 1267, Dalichai Formation.
Dimensions: Holotype; length 46 μm, breadth 35 μm, processes 34 μm. Paratype; length 35 μm (without operculum), breadth 29 μm, processes 45 μm. Range: length 34 (46) 58 μm, breadth 26 (34) 50 μm (51 specimens measured).
Remarks: The presence of the unusual process located near the antapex leads to the speculation that C. ovula may be closely related - perhaps indeed ancestral - to the corona-bearing cyst genus Stephanelytron. It is perfectly conceivable, despite the complexity of their internal structure, that the coronas of the Stephanelytraceae evolved from a single process. This accords well with the hypothesis of their evolutionary relationship advanced by Piel, 1985 (pp. 116, 118, figure 4). An ectophragm is present in 38% of the Dalichai specimens. The most similar species of this genus hitherto described is Chlamydophorella raritubulae Dodekova 1975, from the Late Bathonian of Bulgaria. This species is more elongate; moreover, it has proportionately larger tubular processes in lower number and exhibiting a greater variety of shape, there being no distinctive antapical process. It is perfectly conceivable, nevertheless, that C. raritubulae may be related, perhaps even ancestral, to C. ovula.
Chlamydophorella ovulum Wheeler and Sarjeant, 1990, p.315–316, pl.12, figs.4–6; text-figs.12a–b ex Wheeler and Sarjeant, 1992, p.381. Holotype: Wheeler and Sarjeant, 1990, pl.12, fig.4. This name was not validly published in Wheeler and Sarjeant (1990), since the lodgement of the holotype was not specified (ICN Article 40.7). NIA. Age: late Callovian–early Oxfordian.
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Original description: [Wheeler and Sarjeant, 1990]:
Chlamydophorella ovulum sp. nov.
Holotype: G. Mus. Pd. 143; 129.8/17.8 Plate 12 fig. 4].
Paratype: G. Mus. Pd. 144; 114.6/20.8 Plate 12 figs. 5-6].
Derivation of name: L. ovulum, diminutive of egg. From the ovoid ambitus.
Diagnosis: Cyst proximate, holocavate and cryptotabulate. Autophragm covered by numerous (c. 200) nontabular processes, which are in turn typically enclosed by a thin ectophragm. Processes short (1/10th cyst length) and of variable diameter, hollow and consistently buccinate in lateral view, the distal terminations being osculate. Often there is a distinctive short, wide subconical process near the antapex.
Archaeopyle apical, Type tA; operculum free.
Material: Sixty-five specimens from samples 1265, 1266 and 1267, Dalichai Formation.
Dimensions: Holotype; length 46 μm, breadth 35 μm, processes 34 μm. Paratype; length 35 μm (without operculum), breadth 29 μm, processes 45 μm. Range: length 34 (46) 58 μm, breadth 26 (34) 50 μm (51 specimens measured).
Remarks: The presence of the unusual process located near the antapex leads to the speculation that C. ovula may be closely related - perhaps indeed ancestral - to the corona-bearing cyst genus Stephanelytron. It is perfectly conceivable, despite the complexity of their internal structure, that the coronas of the Stephanelytraceae evolved from a single process. This accords well with the hypothesis of their evolutionary relationship advanced by Piel, 1985 (pp. 116, 118, figure 4). An ectophragm is present in 38% of the Dalichai specimens. The most similar species of this genus hitherto described is Chlamydophorella raritubulae Dodekova 1975, from the Late Bathonian of Bulgaria. This species is more elongate; moreover, it has proportionately larger tubular processes in lower number and exhibiting a greater variety of shape, there being no distinctive antapical process. It is perfectly conceivable, nevertheless, that C. raritubulae may be related, perhaps even ancestral, to C. ovula.