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Elytrocysta
From Fensome et al., 2019:
Elytrocysta, Stover and Evitt, 1978, p.43–44.
Type: Drugg, 1967, pl.5, fig.12, as Membranosphaera maastrichtica.
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Original description: [Stover and Evitt, 1978]:
Synopsis:
Cysts proximate, holocavate, subspherical; autocyst with numerous short, nontabular projections or low, discontinuous ridges covered distally by thin ectophragm; indications of paratabulation other than archeopyle typically absent or faint; archeopyle apical, Type tA or tAa.
Description:
Shape: Subspherical.
Wall relationships: Cysts holocavate; autophragm and ectophragm narrowly and more or less uniformly separated; ectocoel with nontabular features.
Wall features: Normally no parasutural features. Autophragm bears numerous short, solid, nontabular projections that are isolated or joined to form short, discontinuous, generally curved ridges, or both.
Paratabulation: Generally indicated by archeopyle only, occasionally also by paracingulum.
Archeopyle: Apical, Types tA or tAa; principal archeopyle suture moderately angular and accessory archeopyle sutures occasionally present; operculum free or attached, and typically small relative to cyst diameter.
Paracingulum: Generally not indicated; may be indicated in the equatorial area by vague transverse alignment of nontabular features, or by a slight depression in the ectophragm seen best along the cyst margin. Indications of paracingulum normally more evident on the dorsal than on the ventral surface.
Parasulcus: Generally not indicated.
Size: Small.
Affinities:
Elytrocysta differs from Kallosphaeridium and Batiacasphaera in possessing an ectophragm, which is lacking in those genera. It differs from Chlamydophorella in that it has solid rather than tubular projections and lacks any trace of an apical projection or horn.
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Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Elytrocysta, Stover and Williams, 1978. Synopsis from Stover and Evitt (1978, p.43) Cysts proximate, holocavate, subspherical; autocyst with numerous short, nontabular projections or low, discontinuous ridges covered distally by thin ectophragm; indications of paratabulation other than archeopyle typically absent or faint. Archeopyle apical, type (tA) or (tA)a.
Elytrocysta, Stover and Evitt, 1978, p.43–44.
Type: Drugg, 1967, pl.5, fig.12, as Membranosphaera maastrichtica.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Stover and Evitt, 1978]:
Synopsis:
Cysts proximate, holocavate, subspherical; autocyst with numerous short, nontabular projections or low, discontinuous ridges covered distally by thin ectophragm; indications of paratabulation other than archeopyle typically absent or faint; archeopyle apical, Type tA or tAa.
Description:
Shape: Subspherical.
Wall relationships: Cysts holocavate; autophragm and ectophragm narrowly and more or less uniformly separated; ectocoel with nontabular features.
Wall features: Normally no parasutural features. Autophragm bears numerous short, solid, nontabular projections that are isolated or joined to form short, discontinuous, generally curved ridges, or both.
Paratabulation: Generally indicated by archeopyle only, occasionally also by paracingulum.
Archeopyle: Apical, Types tA or tAa; principal archeopyle suture moderately angular and accessory archeopyle sutures occasionally present; operculum free or attached, and typically small relative to cyst diameter.
Paracingulum: Generally not indicated; may be indicated in the equatorial area by vague transverse alignment of nontabular features, or by a slight depression in the ectophragm seen best along the cyst margin. Indications of paracingulum normally more evident on the dorsal than on the ventral surface.
Parasulcus: Generally not indicated.
Size: Small.
Affinities:
Elytrocysta differs from Kallosphaeridium and Batiacasphaera in possessing an ectophragm, which is lacking in those genera. It differs from Chlamydophorella in that it has solid rather than tubular projections and lacks any trace of an apical projection or horn.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Elytrocysta, Stover and Williams, 1978. Synopsis from Stover and Evitt (1978, p.43) Cysts proximate, holocavate, subspherical; autocyst with numerous short, nontabular projections or low, discontinuous ridges covered distally by thin ectophragm; indications of paratabulation other than archeopyle typically absent or faint. Archeopyle apical, type (tA) or (tA)a.