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Baileyella daveyi
Baileyella daveyi, (Bailey, 1987, p. 89,91,94, pl.1, figs.1–5; pl.2, figs.1–11; text-figs.2A–D), (Özdikmen, 2009, p.234).
Originally (and now) Durotrigia, subsequently Baileyella (generic name illegitimate). Although Özdikmen, 2009, did not fully reference the basionym when proposing the transfer of this species to Baileyella, he did so under the aegis of the I.C.Z.N., so the combination can be considered validly published.
Holotype: Bailey, 1987, pl.2, figs.1,4,9; Fensome et al., 1993a, figs.1–2 — p.1095.
Paratype: Bailey, 1987.
Locus typicus: British Geological Survey borehole 50/03 329, Lyme Bay, southern England.
Age: early Bajocian.
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Original description: Bailey, 1987, p. 89-91
Diagnosis:
Cyst sub-spherical, proximate or proximochorate.
Gonyaulacacean tabulation: 1acl, 1pr, 4', 2a, 6", 6c, 6''', 1p, 1'''', 5s, flagellar pore area.
The archaeopyle is formed by the loss of 1 to 5 precingular plates (1P-5P).
The autophragm is well tabulated, with distinct sutural ridges surmounted by isolated projections and/or crests, which may be perforate.
Description:
Shape: Cyst subspherical.
Wall Relationships: Autophragm only.
Wall Features: Sutural features include low ridges, usually surmounted by isolated projections and/or denticulate crests which may be perforate. The spines / denticulations may be distally bifurcate, and tend to be more complex about the cingulum and antapical pole. Gonal spines are also large. The autophragm has a complex structure (see Bailey, 1987, Pl. 1, fig. 5), appearing scabrate in transmitted light.
Tabulation: Indicated by variable, but distinct sutural features. Gonyaulacacean formula: 1acl, 1pr, 4', 2a, 6", 6c, 6''', 1p, 1'''', 5s, flagellar pore area.
Archaeopyle: Precingular, formed by the loss of up to five precingular plates. Cysts with varying dehiscence; 1P, 2P, 3P, 4P and 5P. The most common type is 4P, with the first and sixth precingulars remaining attached, forming a broad isthmus joining the apical series to the hypocyst. Excystment begins dorsally at the 3" plate and progresses ventrally in both directions.
Cingulum: Indicated by six rectangular plates. Cingular sutures often carry complex denticulate crests which may be perforate and bear bifurcate spines (Bailey, 1987, Fig. 2c). - Ornamentation is symmetrical about the cingulum.
Sulcus: Clearly discernible. The innermost part of the sulcus is occupied by a large flagellar pore area where no detail can be distinguished. Surrounding this area are five sulcal plates: as, ras, rs, ps, ls.
Originally (and now) Durotrigia, subsequently Baileyella (generic name illegitimate). Although Özdikmen, 2009, did not fully reference the basionym when proposing the transfer of this species to Baileyella, he did so under the aegis of the I.C.Z.N., so the combination can be considered validly published.
Holotype: Bailey, 1987, pl.2, figs.1,4,9; Fensome et al., 1993a, figs.1–2 — p.1095.
Paratype: Bailey, 1987.
Locus typicus: British Geological Survey borehole 50/03 329, Lyme Bay, southern England.
Age: early Bajocian.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: Bailey, 1987, p. 89-91
Diagnosis:
Cyst sub-spherical, proximate or proximochorate.
Gonyaulacacean tabulation: 1acl, 1pr, 4', 2a, 6", 6c, 6''', 1p, 1'''', 5s, flagellar pore area.
The archaeopyle is formed by the loss of 1 to 5 precingular plates (1P-5P).
The autophragm is well tabulated, with distinct sutural ridges surmounted by isolated projections and/or crests, which may be perforate.
Description:
Shape: Cyst subspherical.
Wall Relationships: Autophragm only.
Wall Features: Sutural features include low ridges, usually surmounted by isolated projections and/or denticulate crests which may be perforate. The spines / denticulations may be distally bifurcate, and tend to be more complex about the cingulum and antapical pole. Gonal spines are also large. The autophragm has a complex structure (see Bailey, 1987, Pl. 1, fig. 5), appearing scabrate in transmitted light.
Tabulation: Indicated by variable, but distinct sutural features. Gonyaulacacean formula: 1acl, 1pr, 4', 2a, 6", 6c, 6''', 1p, 1'''', 5s, flagellar pore area.
Archaeopyle: Precingular, formed by the loss of up to five precingular plates. Cysts with varying dehiscence; 1P, 2P, 3P, 4P and 5P. The most common type is 4P, with the first and sixth precingulars remaining attached, forming a broad isthmus joining the apical series to the hypocyst. Excystment begins dorsally at the 3" plate and progresses ventrally in both directions.
Cingulum: Indicated by six rectangular plates. Cingular sutures often carry complex denticulate crests which may be perforate and bear bifurcate spines (Bailey, 1987, Fig. 2c). - Ornamentation is symmetrical about the cingulum.
Sulcus: Clearly discernible. The innermost part of the sulcus is occupied by a large flagellar pore area where no detail can be distinguished. Surrounding this area are five sulcal plates: as, ras, rs, ps, ls.