Back
Egmontodinium toryna
From Fensome et al., 2019:
Egmontodinium torynum (Cookson and Eisenack, 1960b, p.252, pl.38, figs.6,15) Davey, 1979c, p.60. Holotype: Cookson and
Eisenack, 1960b, pl.38, fig.15. Originally Hystrichosphaeridium, subsequently Prolixosphaeridium?, thirdly
Tanyosphaeridium, fourthly (and now) Egmontodinium. NIA. Age: Tithonian–Neocomian.
---------------------------------------------------------------------------------------------------
Original description: Cookson and Eisenack, 1960, p. 252: Hystrichosphaeridium torynum
Shell cylindrical with rounded ends and numerous short and apparently solid appendages of variable shape and size which are arranged in more or less well-defined whorls around the circumference. The appendages are either narrow and simple with capitate ends or flattened and terminally branched. The opening of the shell appears to have been terminal (Pl. 38, fig. 6).
Dimensions: holotype-shell 68 µm long, 33 µm broad; overall 81-56 µm. Appendages c. 10 µm long. Range of shell 64-78 µm x 32-38 µm.
Remarks:
Davey, 1979, p. 60: Egmontodinium torynum is considered to be related to E. polyplacophorum through the intermediate form, E. sp. A. (Davey, 1979, p. 61: here the cingular crests have generally broken down to leave mainly the pre- and postcingular sutural and penetabular crests; these bear processes like those of E. torynum).
In E. torynum, the parasutural crests are lost and there remain only longitudinally arranged rows of membranous processes. The elongate pericyst shape is retained.
---------------------------------------------------------------------------------------------------
Vitacca et al., 2022:
Emended diagnosis: A species of Egmontodinium with a smooth to granulate autophragmadorned by strongly capitate to bifurcate, sutural and intratabular (rare) processes. Tabulation gonyaulacacean, archeopyle apical, Type (tA), operculum free.
Description: An intermediate-sized, elongate ellipsoidal, acavate dinoflagellate cyst with a smooth to granulate autophragm adorned by strongly capitate to bifurcate sutural processes. Processes are relatively wide, solid and variably circular to flattened in cross-section.When bifurcate, branching typically occurs in the distal third of a process and when capitate, the distal flare is pronounced. Intratabular processes are relatively uncommon. Standard gonyaulacacean tabulation indicated by the sutural processes; formula:?pr, 4′, 6″,?c, 6″’, 1p, 1″”,?s. Archeopyle apical, Type (tA), operculum free.
Remarks: The genus is herein emended to note the precise nature of process insertion: primarily sutural, rarely intrabular, and not longitudinal, as suggested by Davey (1979).
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Egmontodinium torynum (Cookson and Eisenack, 1960b) Davey, 1979c, is cylindrical with rounded ends and numerous short and apparently solid appendages of variable shape and size which are arranged in more or less well-defined whorls around the circumference. The processes are either narrow and simple with capitate ends or flattened and terminally branched. The archeopyle is apical. Size: overall 56-81 µm, processes ca. 10 µm long, range of shell 64-78 x 32-38 µm.
--------------------------------------------------
Egmontodinium torynum (Cookson and Eisenack, 1960b, p.252, pl.38, figs.6,15) Davey, 1979c, p.60. Holotype: Cookson and
Eisenack, 1960b, pl.38, fig.15. Originally Hystrichosphaeridium, subsequently Prolixosphaeridium?, thirdly
Tanyosphaeridium, fourthly (and now) Egmontodinium. NIA. Age: Tithonian–Neocomian.
---------------------------------------------------------------------------------------------------
Original description: Cookson and Eisenack, 1960, p. 252: Hystrichosphaeridium torynum
Shell cylindrical with rounded ends and numerous short and apparently solid appendages of variable shape and size which are arranged in more or less well-defined whorls around the circumference. The appendages are either narrow and simple with capitate ends or flattened and terminally branched. The opening of the shell appears to have been terminal (Pl. 38, fig. 6).
Dimensions: holotype-shell 68 µm long, 33 µm broad; overall 81-56 µm. Appendages c. 10 µm long. Range of shell 64-78 µm x 32-38 µm.
Remarks:
Davey, 1979, p. 60: Egmontodinium torynum is considered to be related to E. polyplacophorum through the intermediate form, E. sp. A. (Davey, 1979, p. 61: here the cingular crests have generally broken down to leave mainly the pre- and postcingular sutural and penetabular crests; these bear processes like those of E. torynum).
In E. torynum, the parasutural crests are lost and there remain only longitudinally arranged rows of membranous processes. The elongate pericyst shape is retained.
---------------------------------------------------------------------------------------------------
Vitacca et al., 2022:
Emended diagnosis: A species of Egmontodinium with a smooth to granulate autophragmadorned by strongly capitate to bifurcate, sutural and intratabular (rare) processes. Tabulation gonyaulacacean, archeopyle apical, Type (tA), operculum free.
Description: An intermediate-sized, elongate ellipsoidal, acavate dinoflagellate cyst with a smooth to granulate autophragm adorned by strongly capitate to bifurcate sutural processes. Processes are relatively wide, solid and variably circular to flattened in cross-section.When bifurcate, branching typically occurs in the distal third of a process and when capitate, the distal flare is pronounced. Intratabular processes are relatively uncommon. Standard gonyaulacacean tabulation indicated by the sutural processes; formula:?pr, 4′, 6″,?c, 6″’, 1p, 1″”,?s. Archeopyle apical, Type (tA), operculum free.
Remarks: The genus is herein emended to note the precise nature of process insertion: primarily sutural, rarely intrabular, and not longitudinal, as suggested by Davey (1979).
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Egmontodinium torynum (Cookson and Eisenack, 1960b) Davey, 1979c, is cylindrical with rounded ends and numerous short and apparently solid appendages of variable shape and size which are arranged in more or less well-defined whorls around the circumference. The processes are either narrow and simple with capitate ends or flattened and terminally branched. The archeopyle is apical. Size: overall 56-81 µm, processes ca. 10 µm long, range of shell 64-78 x 32-38 µm.
--------------------------------------------------