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Senoniasphaera inornata
From Fensome et al., 2019:
Senoniasphaera inornata (Drugg, 1970b, p.811–812, figs.3C–F) Stover and Evitt, 1978, p.80. Holotype: Drugg, 1970b, fig.3C; Fensome et al., 2019a, fig.16H. Originally Chiropteridium, subsequently (and now) Senoniasphaera. Age: Danian.
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Original description: Drugg, 1970, p. 811-812: Chiropteridium inornatum
Double-walled cavate cyst. Endophragm 2 to 3 µm thick forming a spherical to somewhat flattened capsule which may have weakly expressed antapical lobes. The surface of this capsule often exhibits scattered punctae. The periphragm is thin, smooth and closely appressed to the capsule dorsoventrally but developing a pericoel laterally and antapically. Sparse and faint supporting processes are sometimes present in a lateral position. The periphragm at the antapex is usually weakly lobed but is sometimes rounded. The periphragm forms a low angled point at the apex. The archeopyle is apical and the operculum is six-sided in outline (see Fig. 3 F). The capsule diameter ranges from 58 to 84µm. The total length (without operculum) ranges from 97 to 101 µm, and the width from 87 to 113 µm.
Affinities:
Drugg, 1970, p. 812: Chiropteridium inornatum
This new species differs from Chiropteridium aspinatum (Gerlach) Brosius, 1963, in that the outer membrane is more clearly and widely separated from the capsule.
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Senoniasphaera inornata (Drugg, 1970b) Stover and Evitt, 1978. S. inornata is a double-walled cavate cyst, with endophragm 2-3 µm thick, and with weakly expressed antapical lobes. The endophragm may be punctate. The periphragm is thin, smooth and closely appressed to the endocyst dorso-ventrally but developing a pericoel laterally and antapically. Sparse and faint supporting processes are sometimes present in a lateral position. Overall length: 97-107 µm, breadth 87-113 µm. Endocyst: 58-84 µm
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Comments Fensome et al., 2019a:
Drugg (1970, p. 811–812) described this species as a double-walled cavate cyst. He noted that the endocyst was spherical to somewhat flattened, with weak antapical lobes possibly present. The periphragm is smooth and appressed to the endophragm dorsoventrally, but with a pericoel ambitally. He noted that “Sparse and faint supporting processes are sometimes present in a lateral position. The species is very similar to, and possibly a taxonomic junior synonym of, Senoniasphaera lordii.
Stratigraphical occurrence. Drugg (1970) recorded Senoniasphaera inornata (as Chiropteridium inornatum) from the Danian of Alabama, USA. Powell (1992) indicated that the FAD of the species is in the Cretaceous and that its LAD is within the Danian (NP4 Zone). Williams et al. (2004) placed its FAD immediately above the base of the Danian and its LAD in the middle Danian in Northern Hemisphere mid-palaeolatitudes
Senoniasphaera inornata (Drugg, 1970b, p.811–812, figs.3C–F) Stover and Evitt, 1978, p.80. Holotype: Drugg, 1970b, fig.3C; Fensome et al., 2019a, fig.16H. Originally Chiropteridium, subsequently (and now) Senoniasphaera. Age: Danian.
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Original description: Drugg, 1970, p. 811-812: Chiropteridium inornatum
Double-walled cavate cyst. Endophragm 2 to 3 µm thick forming a spherical to somewhat flattened capsule which may have weakly expressed antapical lobes. The surface of this capsule often exhibits scattered punctae. The periphragm is thin, smooth and closely appressed to the capsule dorsoventrally but developing a pericoel laterally and antapically. Sparse and faint supporting processes are sometimes present in a lateral position. The periphragm at the antapex is usually weakly lobed but is sometimes rounded. The periphragm forms a low angled point at the apex. The archeopyle is apical and the operculum is six-sided in outline (see Fig. 3 F). The capsule diameter ranges from 58 to 84µm. The total length (without operculum) ranges from 97 to 101 µm, and the width from 87 to 113 µm.
Affinities:
Drugg, 1970, p. 812: Chiropteridium inornatum
This new species differs from Chiropteridium aspinatum (Gerlach) Brosius, 1963, in that the outer membrane is more clearly and widely separated from the capsule.
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Senoniasphaera inornata (Drugg, 1970b) Stover and Evitt, 1978. S. inornata is a double-walled cavate cyst, with endophragm 2-3 µm thick, and with weakly expressed antapical lobes. The endophragm may be punctate. The periphragm is thin, smooth and closely appressed to the endocyst dorso-ventrally but developing a pericoel laterally and antapically. Sparse and faint supporting processes are sometimes present in a lateral position. Overall length: 97-107 µm, breadth 87-113 µm. Endocyst: 58-84 µm
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Comments Fensome et al., 2019a:
Drugg (1970, p. 811–812) described this species as a double-walled cavate cyst. He noted that the endocyst was spherical to somewhat flattened, with weak antapical lobes possibly present. The periphragm is smooth and appressed to the endophragm dorsoventrally, but with a pericoel ambitally. He noted that “Sparse and faint supporting processes are sometimes present in a lateral position. The species is very similar to, and possibly a taxonomic junior synonym of, Senoniasphaera lordii.
Stratigraphical occurrence. Drugg (1970) recorded Senoniasphaera inornata (as Chiropteridium inornatum) from the Danian of Alabama, USA. Powell (1992) indicated that the FAD of the species is in the Cretaceous and that its LAD is within the Danian (NP4 Zone). Williams et al. (2004) placed its FAD immediately above the base of the Danian and its LAD in the middle Danian in Northern Hemisphere mid-palaeolatitudes