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Stenopyxinium
From Williams et al., 2017:
[Stenopyxinium, Deflandre, 1968, p. 424
Type species: Stenopyxinium grassei, Deflandre, 1968 (figs.1–3)]
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Original description: [Deflandre, 1968]: (Translation: Stover and Evitt, 1978, p. 221):
Description:
Theca of organic matter, clear brownish color, aspect trilobate, composed of a body with a rounded bilobate base surmounted by a cylindrical band capped with a hemispherical calotte closing the archeopyle.
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Modified description:
Stover and Evitt, 1978, p. 221-222:
Synopsis:
Cysts small, outline trilobate, with short spines at the apical and antapical ends; archeopyle type uncertain, probably "tAtP".
Description:
Shape: Flasklike, outline moderately to strongly trilobate, constructed equatorially.
Wall relationships: Autophragm only.
Wall features: No parasutural features. Autophragm has a few short spines along the apical and antapical margins, otherwise smooth.
Paratabulation: Indicated essentially by the archeopyle.
Archeopyle: Type uncertain, probably "tAtP"; principal archeopyle suture appears to be immediately anterior to paracingulum; operculum hemispherical; constituent paraplates not delimited.
Paracingulum: Suggested by constricted annulate band approximately at midlength.
Parasulcus: Not indicated.
Size: Small (unusually so, less than 20 μm).
Affinities:
Stenopyxinium differs from Cauca in having relatively short spines rather than long, simple, hollow processes. Dorocysta is similar to Stenopyxinium, but has an apical rather than a combination archeopyle.
[Stenopyxinium, Deflandre, 1968, p. 424
Type species: Stenopyxinium grassei, Deflandre, 1968 (figs.1–3)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Deflandre, 1968]: (Translation: Stover and Evitt, 1978, p. 221):
Description:
Theca of organic matter, clear brownish color, aspect trilobate, composed of a body with a rounded bilobate base surmounted by a cylindrical band capped with a hemispherical calotte closing the archeopyle.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:
Stover and Evitt, 1978, p. 221-222:
Synopsis:
Cysts small, outline trilobate, with short spines at the apical and antapical ends; archeopyle type uncertain, probably "tAtP".
Description:
Shape: Flasklike, outline moderately to strongly trilobate, constructed equatorially.
Wall relationships: Autophragm only.
Wall features: No parasutural features. Autophragm has a few short spines along the apical and antapical margins, otherwise smooth.
Paratabulation: Indicated essentially by the archeopyle.
Archeopyle: Type uncertain, probably "tAtP"; principal archeopyle suture appears to be immediately anterior to paracingulum; operculum hemispherical; constituent paraplates not delimited.
Paracingulum: Suggested by constricted annulate band approximately at midlength.
Parasulcus: Not indicated.
Size: Small (unusually so, less than 20 μm).
Affinities:
Stenopyxinium differs from Cauca in having relatively short spines rather than long, simple, hollow processes. Dorocysta is similar to Stenopyxinium, but has an apical rather than a combination archeopyle.