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Rotosphaeropsis munu
Rhotosphaeropsis munu Davey, 1988
Holotype: Davey,1987, pl.10, fig.1,5
Locus typicus: Papuan Basin, Papua New Guinea
Stratum typicum: Valanginian
Original diagnosis: Davey, 1988, p. 45-46
Shape: Ovoidal with minor dorso-ventral flattening.
Wall: Relatively thin, apparently two-layered with the outer layer giving rise to sutural processes and trabeculae.
Wall features: Numerous sutural, gonal and intergonal processes are present and distally support irregular trabeculae. The processes are of variable thickness, of approximately constant height and may show some medial to distal cross-linkage with adjacent processes below the trabeculae. The latter vary slightly in thickness and may bear spines.Paratabulation: Sutural ridges or crests are not discernible. The complex trabeculae are typically distorted and so do not reflect a meaningful tabulation. Archaeopyle: Precingular, Type P (3" only); operculum free.
Size: Large. Dimensions: Body length 73-89 µm ; body width 42-54 µm; maximum height of processes 43 µm.
Original description: Davey, 1987, p. 46
Because of the thin nature of many of the sutural processes and of the trabeculae, they are often deformed and sometimes broken. Their complex nature gives the cyst an unorganised appearance and orientation of the cyst must be affected by location of the archaeopyle in relation to the cyst elongation. Both processes and trabeculae are mainly flat or lamellar in cross-section.
Affinities:
Davey, 1987, p. 46: The combination of ovoidal body, numerous sutural processes supporting irregular trabeculae and a precingular archaeopyle differentiates Rotosphaeropsis munu from all previously described taxa. Cannosphaeropsis thula Davey 1982 is basically similar, but is smaller and bears slmpler processes and trabeculae. Distribution. Rotosphaeropsis munu is confined to the Systematophora areolata and Avellodinium flagellatum Zones (samples MND 256-253) of the Valanginian in the Strickland sections. It is here typically common to abundant and is an important stratigraphic marker in the present region.
Holotype: Davey,1987, pl.10, fig.1,5
Locus typicus: Papuan Basin, Papua New Guinea
Stratum typicum: Valanginian
Original diagnosis: Davey, 1988, p. 45-46
Shape: Ovoidal with minor dorso-ventral flattening.
Wall: Relatively thin, apparently two-layered with the outer layer giving rise to sutural processes and trabeculae.
Wall features: Numerous sutural, gonal and intergonal processes are present and distally support irregular trabeculae. The processes are of variable thickness, of approximately constant height and may show some medial to distal cross-linkage with adjacent processes below the trabeculae. The latter vary slightly in thickness and may bear spines.Paratabulation: Sutural ridges or crests are not discernible. The complex trabeculae are typically distorted and so do not reflect a meaningful tabulation. Archaeopyle: Precingular, Type P (3" only); operculum free.
Size: Large. Dimensions: Body length 73-89 µm ; body width 42-54 µm; maximum height of processes 43 µm.
Original description: Davey, 1987, p. 46
Because of the thin nature of many of the sutural processes and of the trabeculae, they are often deformed and sometimes broken. Their complex nature gives the cyst an unorganised appearance and orientation of the cyst must be affected by location of the archaeopyle in relation to the cyst elongation. Both processes and trabeculae are mainly flat or lamellar in cross-section.
Affinities:
Davey, 1987, p. 46: The combination of ovoidal body, numerous sutural processes supporting irregular trabeculae and a precingular archaeopyle differentiates Rotosphaeropsis munu from all previously described taxa. Cannosphaeropsis thula Davey 1982 is basically similar, but is smaller and bears slmpler processes and trabeculae. Distribution. Rotosphaeropsis munu is confined to the Systematophora areolata and Avellodinium flagellatum Zones (samples MND 256-253) of the Valanginian in the Strickland sections. It is here typically common to abundant and is an important stratigraphic marker in the present region.