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Canningia glomerata
From Fensome et al., 2019:
Canningia glomerata Fensome et al., 2019a, p.23.
Emendation: Prince et al., 1999, p.162, as Senoniasphaera rotundata.
Holotype: Clarke and Verdier, 1967, pl.14, fig.2; Fensome et al., 2019a, fig.12O.
Originally Senoniasphaera rotundata, subsequently (and now) Canningia glomerata.
This is the substitute name for Senoniasphaera rotundata, necessary because the name Canningia rotundata Cookson and Eisenack already exists.
Age: Santonian–Campanian.
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Senoniasphaera rotundata Clarke and Verdier, 1967; Emendation: Prince et al., 1999, p.162.
Holotype:Clarke and Verdier 1967, pl.14, fig.2
Locus typicus: Culver Cliff, I.O.W, England
Stratum typicum: Senonian
Original diagnosis: Clarke and Verdier, 1967, p. 62-63
A species of Senoniasphaera in which the outer membrane is detached from the inner body to form one apical, two antapical and frequently two lateral horns.
Original description: Clarke and Verdier, 1967, p.63
Inner body rounded which seldom protrudes into the horns. Wall thickness 1-2 µm. In the ideal case the outer membrane is closely attached to the inner body by short perforated pillars except where the membrane is detached and expanded to form the horns. In atypical forms (pl. 14, fig. 3) the outer membrane is detached over a larger and more irregular area and the attachment pillars become more visible. The position of the antapical horns is not always symmetrical with respect to the long axis and they are generally of unequal size; the same applies to the lateral horns. A girdle is present and its edge can be seen on the lateral horns; its displacement ventrally is slight although the interruption may be considerable. The plate system is not always clearly displayed and even in the most clear cases it is not possible to resolve the actual position of the tabulation. The longitudinal furrow is obscure. A well defined apical archaeopyle is present which can also be observed in complete specimens (pl. 14, figs. 1-2). The sculpture is a combination of perforations and an irregular reticulum, the muri being fairly thick.
Measurements: Holotype Overall length 92 µm, overall breadth 67 µm, Length of inner body 71 µm, breadth of inner body 60 µm, length of apical horn 14 µm, length of antapical horns 8,2 µm, width of transverse furrow 3 µm.
Affinities:
Clarke and Verdier, 1967, p.63: S. rotundata differs from S. protrusa in the absence of inner body protrusions into the horns, and in the presence of a reticulum.
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Comments Fensome et al., 2019a:
1967 Senoniasphaera rotundata Clarke & Verdier, p. 62–63, pl. 14, figs 1–3; text-fig. 25.1999 Senoniasphaera rotundata Clarke & Verdier; emend. Prince et al., p. 162.
Derivation of name. From the Latin glomeratus, formed into a ball, in reference to the shape of the inner body, following the intent of the original species epithet.
Comments. This species was proposed (as Senoniasphaera rotundata) by Clarke and Verdier (Citation1967, p. 62–63) essentially for forms of Senoniasphaera in which the inner body ‘seldom protrudes into the horns’ and with ornament consisting of ‘a combination of perforations and an irregular reticulum’. They noted that:
In the ideal case the outer membrane is closely attached to the inner body [i.e. autocyst/autophragm] by short perforated pillars except where the membrane is detached and expanded to form the horns. In atypical forms … the outer membrane is detached over a larger and more irregular area and the attachment pillars become more visible.
This species is thus holocavate with a relatively dense arrangements of connecting structures between wall layers. Thus, we transfer it to Canningia under the substitute name Canningia glomerata. The new epithet is necessary because the name Canningia rotundata is preoccupied (Canningia rotundata Cookson & Eisenack Citation1961).
Stratigraphical occurrence. Clarke and Verdier (Citation1967) recorded Canningia glomerata (as Senoniasphaera rotundata) from the Senonian of the Isle of Wight, England. [Regarding ‘Senonian’, see discussion under Aptea rotundata; we are uncertain as to exactly how Clarke and Verdier (Citation1967) used this term.] Costa and Davey (Citation1992) gave its stratigraphical range as earliest Coniacian to early Maastrichtian. Stover et al. (Citation1996) considered the species to range from the Coniacian to early Maastrichtian. Williams et al. (Citation2004) placed its first appearance datum (FAD) within the early Turonian and its last appearance datum (LAD) within the late Campanian.
Canningia glomerata Fensome et al., 2019a, p.23.
Emendation: Prince et al., 1999, p.162, as Senoniasphaera rotundata.
Holotype: Clarke and Verdier, 1967, pl.14, fig.2; Fensome et al., 2019a, fig.12O.
Originally Senoniasphaera rotundata, subsequently (and now) Canningia glomerata.
This is the substitute name for Senoniasphaera rotundata, necessary because the name Canningia rotundata Cookson and Eisenack already exists.
Age: Santonian–Campanian.
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Senoniasphaera rotundata Clarke and Verdier, 1967; Emendation: Prince et al., 1999, p.162.
Holotype:Clarke and Verdier 1967, pl.14, fig.2
Locus typicus: Culver Cliff, I.O.W, England
Stratum typicum: Senonian
Original diagnosis: Clarke and Verdier, 1967, p. 62-63
A species of Senoniasphaera in which the outer membrane is detached from the inner body to form one apical, two antapical and frequently two lateral horns.
Original description: Clarke and Verdier, 1967, p.63
Inner body rounded which seldom protrudes into the horns. Wall thickness 1-2 µm. In the ideal case the outer membrane is closely attached to the inner body by short perforated pillars except where the membrane is detached and expanded to form the horns. In atypical forms (pl. 14, fig. 3) the outer membrane is detached over a larger and more irregular area and the attachment pillars become more visible. The position of the antapical horns is not always symmetrical with respect to the long axis and they are generally of unequal size; the same applies to the lateral horns. A girdle is present and its edge can be seen on the lateral horns; its displacement ventrally is slight although the interruption may be considerable. The plate system is not always clearly displayed and even in the most clear cases it is not possible to resolve the actual position of the tabulation. The longitudinal furrow is obscure. A well defined apical archaeopyle is present which can also be observed in complete specimens (pl. 14, figs. 1-2). The sculpture is a combination of perforations and an irregular reticulum, the muri being fairly thick.
Measurements: Holotype Overall length 92 µm, overall breadth 67 µm, Length of inner body 71 µm, breadth of inner body 60 µm, length of apical horn 14 µm, length of antapical horns 8,2 µm, width of transverse furrow 3 µm.
Affinities:
Clarke and Verdier, 1967, p.63: S. rotundata differs from S. protrusa in the absence of inner body protrusions into the horns, and in the presence of a reticulum.
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Comments Fensome et al., 2019a:
1967 Senoniasphaera rotundata Clarke & Verdier, p. 62–63, pl. 14, figs 1–3; text-fig. 25.1999 Senoniasphaera rotundata Clarke & Verdier; emend. Prince et al., p. 162.
Derivation of name. From the Latin glomeratus, formed into a ball, in reference to the shape of the inner body, following the intent of the original species epithet.
Comments. This species was proposed (as Senoniasphaera rotundata) by Clarke and Verdier (Citation1967, p. 62–63) essentially for forms of Senoniasphaera in which the inner body ‘seldom protrudes into the horns’ and with ornament consisting of ‘a combination of perforations and an irregular reticulum’. They noted that:
In the ideal case the outer membrane is closely attached to the inner body [i.e. autocyst/autophragm] by short perforated pillars except where the membrane is detached and expanded to form the horns. In atypical forms … the outer membrane is detached over a larger and more irregular area and the attachment pillars become more visible.
This species is thus holocavate with a relatively dense arrangements of connecting structures between wall layers. Thus, we transfer it to Canningia under the substitute name Canningia glomerata. The new epithet is necessary because the name Canningia rotundata is preoccupied (Canningia rotundata Cookson & Eisenack Citation1961).
Stratigraphical occurrence. Clarke and Verdier (Citation1967) recorded Canningia glomerata (as Senoniasphaera rotundata) from the Senonian of the Isle of Wight, England. [Regarding ‘Senonian’, see discussion under Aptea rotundata; we are uncertain as to exactly how Clarke and Verdier (Citation1967) used this term.] Costa and Davey (Citation1992) gave its stratigraphical range as earliest Coniacian to early Maastrichtian. Stover et al. (Citation1996) considered the species to range from the Coniacian to early Maastrichtian. Williams et al. (Citation2004) placed its first appearance datum (FAD) within the early Turonian and its last appearance datum (LAD) within the late Campanian.