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Moorodinium simplex
Moorodinium simplex Backhouse, 1988
Holotype: Backhouse, 1988, pl.34, fig.4
Locus typicus: Perth Basin, W Australia
Stratum typicum: Late Thithonian-?earliest Valanginian
Original description: Backhouse, 1988, p.99-100
Small, ovoid. proximate cysts with a preferred lateral orientation. Wall very thin, may be single-layered or composed of two thin layers appressed over most of cyst surface. Slight cavation may be developed in antapical area. Epicyst bears low, narrow? dorso-ventral septa less than 2 Ám high. Hypocyst without discernible paratabulation, lacking spines. Paracingulum indicated by low transverse ridges? 3 to 4 Ám wide, not visibly offset. Parasulcus not indicated, or obscured by orientation. Archeopyle combination epicystal, type [tA, tP], operculum usually attached for part of circumference. Primary archeopyle suture situated along anterior margin of paracingulum.
Dimensions: Length of holotype 35 Ám, width 29 Ám. Range of length (21 specimens) 30(35)39 Ám, width 24(29)33 Ám.
Affinities:
Backhouse, 1988, p.100: Mooradinium simplex is distinguished from other species of Moorodinium by its small size and lack of discernible hypocystal surface features. The paracingulum is the only evidence of paratabulation on most specimens. Because of its small size and the difficulties of observation, the morphology of this species is less well-known than other members of the Moorodinium cyst-lineage.
Holotype: Backhouse, 1988, pl.34, fig.4
Locus typicus: Perth Basin, W Australia
Stratum typicum: Late Thithonian-?earliest Valanginian
Original description: Backhouse, 1988, p.99-100
Small, ovoid. proximate cysts with a preferred lateral orientation. Wall very thin, may be single-layered or composed of two thin layers appressed over most of cyst surface. Slight cavation may be developed in antapical area. Epicyst bears low, narrow? dorso-ventral septa less than 2 Ám high. Hypocyst without discernible paratabulation, lacking spines. Paracingulum indicated by low transverse ridges? 3 to 4 Ám wide, not visibly offset. Parasulcus not indicated, or obscured by orientation. Archeopyle combination epicystal, type [tA, tP], operculum usually attached for part of circumference. Primary archeopyle suture situated along anterior margin of paracingulum.
Dimensions: Length of holotype 35 Ám, width 29 Ám. Range of length (21 specimens) 30(35)39 Ám, width 24(29)33 Ám.
Affinities:
Backhouse, 1988, p.100: Mooradinium simplex is distinguished from other species of Moorodinium by its small size and lack of discernible hypocystal surface features. The paracingulum is the only evidence of paratabulation on most specimens. Because of its small size and the difficulties of observation, the morphology of this species is less well-known than other members of the Moorodinium cyst-lineage.