Back
Polygonifera
From Williams et al., 2017:
[Polygonifera, Habib, 1972, p. 376; Emendation: Mehrotra and Sarjeant, 1984c, p. 46.
Tax. jr. syn.: Ambonosphaera, according to Brenner (1988, p.68) — however, Prauss (1989, p.31) retained Ambonosphaera; Leberidocysta, according to Mehrotra and Sarjeant (1984c, p.46) — however, Lentin and Williams (1985, p.214) retained Leberidocysta.
Type species: Polygonifera evittii, Habib, 1972 (pl.5, figs.1a–b)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Habib, 1972]:
Description:
Cavate cysts of polygonal to oval shape; archeopyle apical, six-sided, and with a sulcal notch. Tabulation not evident. Capsule more-or-less oval. It is appressed to one surface of the outer membrane. Antapical pericoel well developed. Cingulum distinct and invariably represents greatest width of cyst.
Affinities:
Polygonifera most closely resembles species of Hexagonifera and Wallodinium from which it is distinguished by its distinctive cingulum.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:
Stover and Evitt, 1978, p. 75:
Synopsis:
Cysts camocavate, subpolyhedral; outline in dorsal-ventral view irregularly polygonal, with clearly delimited paracingulum and an apical archeopyle; other indications of paratabulation lacking; eccentricity of periphragm to endophragm seen in lateral view.
Description:
Shape: Subpolyhedral, outline somewhat hexagonal, but outline of apical margin with operculum in place unknown; outline in lateral view elliptical.
Wall relationships: Cysts camocavate; periphragm and endophragm appressed dorsally, separated elsewhere; endophragm broadly ellipsoidal.
Wall features: No parasutural features. Periphragm thin, folded, scabrate to granulate.
Paratabulation: Expressed by archeopyle and paracingulum; formula unknown.
Archeopyle: Apical, apparently Type (tA); principal archeopyle suture angular with deep parasulcal notch; operculum free, exact shape unknown.
Paracingulum: Indicated by equatorial, parallel, transverse folds in the periphragm, which border a shallow concavity; paracingulum protrusive laterally.
Parasulcus: Not indicated.
Size: Small to intermediate.
Affinities:
Polygonifera is similar to Dingodinium in that each has an eccentrically place endocyst with respect to the pericyst. However, the archeopyle type in Dingodinium is unknown, and the genus commonly has an apical horn. It is not known whether or not Polygonifera possesses an apical horn. Further study may demonstrate that Polygonifera and Dingodinium are congeneric.
[Polygonifera, Habib, 1972, p. 376; Emendation: Mehrotra and Sarjeant, 1984c, p. 46.
Tax. jr. syn.: Ambonosphaera, according to Brenner (1988, p.68) — however, Prauss (1989, p.31) retained Ambonosphaera; Leberidocysta, according to Mehrotra and Sarjeant (1984c, p.46) — however, Lentin and Williams (1985, p.214) retained Leberidocysta.
Type species: Polygonifera evittii, Habib, 1972 (pl.5, figs.1a–b)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Habib, 1972]:
Description:
Cavate cysts of polygonal to oval shape; archeopyle apical, six-sided, and with a sulcal notch. Tabulation not evident. Capsule more-or-less oval. It is appressed to one surface of the outer membrane. Antapical pericoel well developed. Cingulum distinct and invariably represents greatest width of cyst.
Affinities:
Polygonifera most closely resembles species of Hexagonifera and Wallodinium from which it is distinguished by its distinctive cingulum.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:
Stover and Evitt, 1978, p. 75:
Synopsis:
Cysts camocavate, subpolyhedral; outline in dorsal-ventral view irregularly polygonal, with clearly delimited paracingulum and an apical archeopyle; other indications of paratabulation lacking; eccentricity of periphragm to endophragm seen in lateral view.
Description:
Shape: Subpolyhedral, outline somewhat hexagonal, but outline of apical margin with operculum in place unknown; outline in lateral view elliptical.
Wall relationships: Cysts camocavate; periphragm and endophragm appressed dorsally, separated elsewhere; endophragm broadly ellipsoidal.
Wall features: No parasutural features. Periphragm thin, folded, scabrate to granulate.
Paratabulation: Expressed by archeopyle and paracingulum; formula unknown.
Archeopyle: Apical, apparently Type (tA); principal archeopyle suture angular with deep parasulcal notch; operculum free, exact shape unknown.
Paracingulum: Indicated by equatorial, parallel, transverse folds in the periphragm, which border a shallow concavity; paracingulum protrusive laterally.
Parasulcus: Not indicated.
Size: Small to intermediate.
Affinities:
Polygonifera is similar to Dingodinium in that each has an eccentrically place endocyst with respect to the pericyst. However, the archeopyle type in Dingodinium is unknown, and the genus commonly has an apical horn. It is not known whether or not Polygonifera possesses an apical horn. Further study may demonstrate that Polygonifera and Dingodinium are congeneric.