Back
Epitricysta
From Williams et al., 2017:
[Epitricysta, Stover and Helby, 1987c, p. 234
Type Species: Epitricysta vinckensis, Stover and Helby, 1987c (figs.8K,9E–G,M–N)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Stover and Helby, 1987]:
Synopsis:
Cysts proximate, oblately spherical to ellipsoidal with a prominent equatorial flange, paratabulation indicated by parasutural ridges or septa;
formula: 3`, 7", Xc, 5``` 1p, 1````, 1 or more s; epicystal paraplates arranged in a pattern similar to that of Triadinium Dodge 1981- archeopyle epicystal, type (tAtP)a.
Description:
Shape. Cysts oblately spherical to ellipsoidal, outline in polar view circular to broadly elliptical; specimens showing preferred apical-antapical orientation.
Wall relationships: Autophragm only.
Wall features: Autophragm faintly ornamented and with parasutural ridges or septa; equatorial flange smooth, or perforate to fenestrate and with an even to spinate outer edge.
Archeopyle: Presumably epicystal, type (tAtP)a, completely separated epicysts and hypocysts not observed; splitting of the epicyst occurring
along the ventral and part of the dorsal margins; the resulting suture anterior and parallel to the equatorial flange.
Paratabulation: Indicated by parasutural features- formula: 3`, 7", Xc, 5```, 1p, 1````, 1 or more s; epicystal paraplates arranged in a pattern similar to that of the epithecal plates on Triadinium Dodge 1981 arrangement of the hypocystal paraplates unlike any previously described.
Paracingulum: Expressed by a single, equatorial flange.
Parasulcus: Position indicated mainly by an interruption in the flange.
Size: Intermediate, between 50 and 100 µm.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Epitricysta Stover and Helby, 1987c, is included in the Cribroperidinioideae by Fensome et al (1993). According to Stover and Helby (1987c, p.234), it has a prominent equatorial flange, paratabulation of 3`, 7", Xc, 5"', 1p, 1"'', and an epicystal archeopyle, and epicystal tabulation similar to that of Triadinium. The epicystal tabulation could be interpreted as 4`, 6", with 1` being metasert.
[Epitricysta, Stover and Helby, 1987c, p. 234
Type Species: Epitricysta vinckensis, Stover and Helby, 1987c (figs.8K,9E–G,M–N)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Stover and Helby, 1987]:
Synopsis:
Cysts proximate, oblately spherical to ellipsoidal with a prominent equatorial flange, paratabulation indicated by parasutural ridges or septa;
formula: 3`, 7", Xc, 5``` 1p, 1````, 1 or more s; epicystal paraplates arranged in a pattern similar to that of Triadinium Dodge 1981- archeopyle epicystal, type (tAtP)a.
Description:
Shape. Cysts oblately spherical to ellipsoidal, outline in polar view circular to broadly elliptical; specimens showing preferred apical-antapical orientation.
Wall relationships: Autophragm only.
Wall features: Autophragm faintly ornamented and with parasutural ridges or septa; equatorial flange smooth, or perforate to fenestrate and with an even to spinate outer edge.
Archeopyle: Presumably epicystal, type (tAtP)a, completely separated epicysts and hypocysts not observed; splitting of the epicyst occurring
along the ventral and part of the dorsal margins; the resulting suture anterior and parallel to the equatorial flange.
Paratabulation: Indicated by parasutural features- formula: 3`, 7", Xc, 5```, 1p, 1````, 1 or more s; epicystal paraplates arranged in a pattern similar to that of the epithecal plates on Triadinium Dodge 1981 arrangement of the hypocystal paraplates unlike any previously described.
Paracingulum: Expressed by a single, equatorial flange.
Parasulcus: Position indicated mainly by an interruption in the flange.
Size: Intermediate, between 50 and 100 µm.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Epitricysta Stover and Helby, 1987c, is included in the Cribroperidinioideae by Fensome et al (1993). According to Stover and Helby (1987c, p.234), it has a prominent equatorial flange, paratabulation of 3`, 7", Xc, 5"', 1p, 1"'', and an epicystal archeopyle, and epicystal tabulation similar to that of Triadinium. The epicystal tabulation could be interpreted as 4`, 6", with 1` being metasert.