Back
Trigonopyxidia
From Williams et al., 2017:
[Trigonopyxidia, Cookson and Eisenack, 1961, p. 75
Substitute name for Trigonopyxis Cookson and Eisenack, 1960a, p.11 (an illegitimate name).
Although the "type species" was not validly transferred by Cookson and Eisenack (1961a, p.75), the generic name Trigonopyxidia was validly published by these authors since it is based on a previously validly published species name (I.C.N. Article 40.3).
Type species: as Trigonopyxis ginella, Cookson and Eisenack, 1960a (pl.3, fig.19)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description as Trigonopyxis: [Cookson and Eisenack, 1960]:
Description:
Shell flat, triangular in outline, partially filled with a capsule.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:
Stover and Evitt, 1978, p. 86:
Synopsis:
Cysts proximate, circumcavate, compressed; outline of pericyst concavely triangular; outline of endocyst concavely triangular to flask-shaped; archeopyle at apex, type uncertain.
Description:
Shape: Outline of pericyst concavely triangular; endocyst concavely triangular to flaskshaped.
Wall relationships: Cysts circumcavate or nearly so; wall layers may be in contact antapically.
Wall features: No parasutural features. Endophragm and periphragm smooth.
Paratabulation: None indicated.
Archeopyle: At apex, type uncertain; sutures straight or nearly so in both periphragm and endophragm; opercula normally free.
Paracingulum: Not indicated.
Parasulcus: Not indicated.
Size: Intermediate.
Affinities:
Trigonopyxidia differs from Paleotetradinium in having a concavely triangular rather than a quadrate outline, and in having the endocyst occupying a greater portion of the pericyst.
[Trigonopyxidia, Cookson and Eisenack, 1961, p. 75
Substitute name for Trigonopyxis Cookson and Eisenack, 1960a, p.11 (an illegitimate name).
Although the "type species" was not validly transferred by Cookson and Eisenack (1961a, p.75), the generic name Trigonopyxidia was validly published by these authors since it is based on a previously validly published species name (I.C.N. Article 40.3).
Type species: as Trigonopyxis ginella, Cookson and Eisenack, 1960a (pl.3, fig.19)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description as Trigonopyxis: [Cookson and Eisenack, 1960]:
Description:
Shell flat, triangular in outline, partially filled with a capsule.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:
Stover and Evitt, 1978, p. 86:
Synopsis:
Cysts proximate, circumcavate, compressed; outline of pericyst concavely triangular; outline of endocyst concavely triangular to flask-shaped; archeopyle at apex, type uncertain.
Description:
Shape: Outline of pericyst concavely triangular; endocyst concavely triangular to flaskshaped.
Wall relationships: Cysts circumcavate or nearly so; wall layers may be in contact antapically.
Wall features: No parasutural features. Endophragm and periphragm smooth.
Paratabulation: None indicated.
Archeopyle: At apex, type uncertain; sutures straight or nearly so in both periphragm and endophragm; opercula normally free.
Paracingulum: Not indicated.
Parasulcus: Not indicated.
Size: Intermediate.
Affinities:
Trigonopyxidia differs from Paleotetradinium in having a concavely triangular rather than a quadrate outline, and in having the endocyst occupying a greater portion of the pericyst.