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Endoceratium
From Williams et al., 2017:
[Endoceratium, Vozzhennikova, 1965, p. 89
Tax. sen. syn.: Pseudoceratium, according to Helby (1987, p.313–315) — however, Lentin and Williams (1989, p.125) retained Endoceratium.
Although the "type species", Endoceratium ludbrookiae, was not validly transferred by Vozzhennikova (1965), the generic name Endoceratium was validly published by that author, since it is based on a previously validly published species name (I.C.N. Article 40.3).
Type species: Ceratocystidiopsis ludbrookiae, Cookson and Eisenack, 1958, (pl.5, fig.7)]
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Original description: [Vozzhennikova, 1965]:
Description:
Cell triangular in outline. Membrane divided into plates. Transverse and longitudinal furrows present. Shape of `internal body` reflects outline of
outer membrane; its surface sculptured.
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Modified description:
Stover and Evitt, 1978, p. 45:
Synopsis:
Cysts circumcavate, compressed ceratioid with three well-developed horns: one apical, one antapical, and one postcingular; paratabulation ceratiacean, indicated by low parasutural ridges; archeopyle apical, Type tA; parasulcal notch offset.
Description:
Shape: Compressed ceratioid with single apical, antapical, and postcingular horns.
Wall relationships: Cysts circumcavate; outline of endophragm convexly triangular; apical horn longer than antapical and postcingular horns.
Wall features: Parasutural features consist of low faint ridges on periphragm. Surface of endophragm and periphragm smooth to punctoreticulate.
Paratabulation: Indicated by parasutural ridges and by archeopyle; ceratiacean, formula: 4`, 6", Xc, 6```, 1p, 1````.
Archeopyle: Apical, Type tA; principal archeopyle suture zigzag; parasulcal notch offset; operculum normally free, but may be adherent.
Paracingulum: Indicated by low, parallel, transverse ridges.
Parasulcus: Expressed as a poorly delimited ovate area near the left margin of the hypocyst; the area may be outlined by a low parasutural ridge.
Size: Large.
Affinities:
Endoceratium differs from Pseudoceratium in being cavate and in having the paratabulation indicated by parasutural ridges. Pseudoceratium is acavate and generally lacks clearly delimited parasutural features.
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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.
Endoceratium Vozzhennikova, 1965. Synopsis from Stover and Evitt (1978, p.45). Cysts circumcavate, compressed ceratioid with three well-developed horns-one apical, one antapical and one postcingular; paratabulation ceratiacean, indicated by low parasutural ridges; archeopyle apical, type (tA); parasulcal notch offset.
[Endoceratium, Vozzhennikova, 1965, p. 89
Tax. sen. syn.: Pseudoceratium, according to Helby (1987, p.313–315) — however, Lentin and Williams (1989, p.125) retained Endoceratium.
Although the "type species", Endoceratium ludbrookiae, was not validly transferred by Vozzhennikova (1965), the generic name Endoceratium was validly published by that author, since it is based on a previously validly published species name (I.C.N. Article 40.3).
Type species: Ceratocystidiopsis ludbrookiae, Cookson and Eisenack, 1958, (pl.5, fig.7)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Vozzhennikova, 1965]:
Description:
Cell triangular in outline. Membrane divided into plates. Transverse and longitudinal furrows present. Shape of `internal body` reflects outline of
outer membrane; its surface sculptured.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:
Stover and Evitt, 1978, p. 45:
Synopsis:
Cysts circumcavate, compressed ceratioid with three well-developed horns: one apical, one antapical, and one postcingular; paratabulation ceratiacean, indicated by low parasutural ridges; archeopyle apical, Type tA; parasulcal notch offset.
Description:
Shape: Compressed ceratioid with single apical, antapical, and postcingular horns.
Wall relationships: Cysts circumcavate; outline of endophragm convexly triangular; apical horn longer than antapical and postcingular horns.
Wall features: Parasutural features consist of low faint ridges on periphragm. Surface of endophragm and periphragm smooth to punctoreticulate.
Paratabulation: Indicated by parasutural ridges and by archeopyle; ceratiacean, formula: 4`, 6", Xc, 6```, 1p, 1````.
Archeopyle: Apical, Type tA; principal archeopyle suture zigzag; parasulcal notch offset; operculum normally free, but may be adherent.
Paracingulum: Indicated by low, parallel, transverse ridges.
Parasulcus: Expressed as a poorly delimited ovate area near the left margin of the hypocyst; the area may be outlined by a low parasutural ridge.
Size: Large.
Affinities:
Endoceratium differs from Pseudoceratium in being cavate and in having the paratabulation indicated by parasutural ridges. Pseudoceratium is acavate and generally lacks clearly delimited parasutural features.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Endoceratium Vozzhennikova, 1965. Synopsis from Stover and Evitt (1978, p.45). Cysts circumcavate, compressed ceratioid with three well-developed horns-one apical, one antapical and one postcingular; paratabulation ceratiacean, indicated by low parasutural ridges; archeopyle apical, type (tA); parasulcal notch offset.