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Senoniasphaera rotundata subsp. rotundata
Senoniasphaera rotundata subsp. rotundata
Autonym. Now redundant.
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.
Autonym. Now redundant.
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.