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Rotosphaeropsis
From Williams et al., 2017:
[Rotosphaeropsis, Davey, 1988, p. 45
Type species: Rotosphaeropsis muna, Davey, 1988 (pl.10, figs.1,5)]
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Original diagnosis: [Davey, 1988]:
Shape: The body is ovoidal.
Wall: Apparently two layered with the outer layer giving rise to processes and trabeculae. Acavate. Surface smooth to scabrate.
Wall Features: Solid, sutural (gonal and intergonal) processes, of variable width, radiate from the cyst surface. Adjacent ones are linked distally by irregular trabeculae which may bear spines. Some additional, sometimes medial, but irregular, linkage may occur between adjacent processes.
Paratabulation: Sutural ridges and crests are absent. Sutural processes, trabeculae and archaeopyle suggest gonyaulacacean affinities.
Archaeopyle: Precingular, Type P (3" only). Operculum free.
Affinities:
The combination of distal trabeculae and precingular archaeopyle differentiates Rotosphaeropsis from most previously described genera. The most similar are Cannosphaeropsis O. Wetzel 1933 emend. Duxbury 1980 and Trabeculidinium Duxbury 1980 which have sutural processes that are both regular in size and spacing and support simple trabeculae. The processes of Rotosphaeropsis are markedly irregular in form and in spacing and support disorderly trabeculae. Nematosphaeropsis Deflandre and Cookson 1955 emend Williams and Downie 1966 has regular processes supporting trabeculae, the former arising from sutural ridges or crests.
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Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Rotosphaeropsis Davey, 1988. Davey (1988, p.45) gave the following diagnosis. Body ovoidal, wall apparently two-layered with the outer layer giving rise to processes and trabeculae. Acavate. Surface smooth to scabrate. Solid, sutural (gonal and intergonal) processes of variable width, radiate from the cyst surface. Adjacent ones are linked distally by irregular trabeculae which may bear spines. Some additional, sometimes medial, but irregular, linkage may occur between adjacent processes. Sutural ridges and crests are absent. Sutural processes, trabeculae and archeopyle suggest gonyaulacacean affinities. Archeopyle precingular, type P (3" only). Operculum free.
[Rotosphaeropsis, Davey, 1988, p. 45
Type species: Rotosphaeropsis muna, Davey, 1988 (pl.10, figs.1,5)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original diagnosis: [Davey, 1988]:
Shape: The body is ovoidal.
Wall: Apparently two layered with the outer layer giving rise to processes and trabeculae. Acavate. Surface smooth to scabrate.
Wall Features: Solid, sutural (gonal and intergonal) processes, of variable width, radiate from the cyst surface. Adjacent ones are linked distally by irregular trabeculae which may bear spines. Some additional, sometimes medial, but irregular, linkage may occur between adjacent processes.
Paratabulation: Sutural ridges and crests are absent. Sutural processes, trabeculae and archaeopyle suggest gonyaulacacean affinities.
Archaeopyle: Precingular, Type P (3" only). Operculum free.
Affinities:
The combination of distal trabeculae and precingular archaeopyle differentiates Rotosphaeropsis from most previously described genera. The most similar are Cannosphaeropsis O. Wetzel 1933 emend. Duxbury 1980 and Trabeculidinium Duxbury 1980 which have sutural processes that are both regular in size and spacing and support simple trabeculae. The processes of Rotosphaeropsis are markedly irregular in form and in spacing and support disorderly trabeculae. Nematosphaeropsis Deflandre and Cookson 1955 emend Williams and Downie 1966 has regular processes supporting trabeculae, the former arising from sutural ridges or crests.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Rotosphaeropsis Davey, 1988. Davey (1988, p.45) gave the following diagnosis. Body ovoidal, wall apparently two-layered with the outer layer giving rise to processes and trabeculae. Acavate. Surface smooth to scabrate. Solid, sutural (gonal and intergonal) processes of variable width, radiate from the cyst surface. Adjacent ones are linked distally by irregular trabeculae which may bear spines. Some additional, sometimes medial, but irregular, linkage may occur between adjacent processes. Sutural ridges and crests are absent. Sutural processes, trabeculae and archeopyle suggest gonyaulacacean affinities. Archeopyle precingular, type P (3" only). Operculum free.