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Rottnestia ovata
Rottnestia ovata Matsuoka and Bujak, 1988
Holotype: Matsuoka and Bujak, 1988, pl.10, fig.1a-b; text-fig.14
Paratype: Matsuoka and Bujak, 1988
Locus typicus: Norton Sound COST No. 1 Well, 6630-6660ft. Norton Sound, Bering Sea
Stratum typicum: Late Oligocene-early Miocene
Original diagnosis: Matsuoka and Bujak, 1988, p.69
Polygonal to elongate, bicavate intermediate proximochorate cyst. Endocyst ovoidal. Granular periphragm and smooth endophragm separated in the apical and antapical region by pericoels. Epicyst hemispherical and slightly smaller than hypocyst, with a poorly developed apical pericoel beneath the small apical horn which possesses a furcate process; hypocyst elongate hemispherical with moderately well-developed pericoel and two larger gonal processes. Parasutural septa low, slightly membranous near the furcate processes, and reflecting the paratabulation 3" (?), 6", 6c, 6""", 1p, xs. Processes mostly gonal, solid, and short with furcate distal extremities. Paracingulum relatively wide and almost circular; parasulcus poorly delimited by parasutural ridges, and almost straight. Archeopyle precingular, formed by the loss of paraplate 3".
Original description: Matsuoka and Bujak, 1988, p.70
The endocyst is ovoidal and the outline of the periphragm is elongate polygonal due to the presence of apical and antapical pericoels. The apical pericoel is small and cornucavate, whereas the antapical pericoel is larger and expanded. The apical horn is small, conical and typically branched. Two projections are present on the antapical area, and are formed by longer gonal processes. Most gonal processes have short solid stalks with trifurcate or sometimes bifurcate endings. The paracingulum is circular and moderately wide. The archeopyle is precingular and formed by the loss of paraplate 3". Dimension: Holotype; length of cyst 53µm, width 33µm, length of apical horn 6µm, height of parasuture 3Ám. Range; length of cyst 38-51µm, width 33-37µm, length of apical horn up to 7µm. Number of specimens measured: 5. Thecal affinities: Unknown; probably related to the Gonyaulacaceae based on its paratabulation and precingular archeopyle.
Matsuoka and Bujak, 1988, p.70:
The presence of gonal processes and bicavation indicates that this species is attributable to the genus Rottnestia. R. ovata differs from R. borussica (Eisenack) in possessing an antapical pericoel and in having a smaller apical horn. R. ovata is similar to Hystrichosphaeropsis arctia, H. variabile and Spiniferites ellipsoideus but is distinguished from the two species of Hystrichosphaeropsis in possessing gonal processes, and from S. ellipsoideus in having more conspicuous apical and antapical pericoels.
Holotype: Matsuoka and Bujak, 1988, pl.10, fig.1a-b; text-fig.14
Paratype: Matsuoka and Bujak, 1988
Locus typicus: Norton Sound COST No. 1 Well, 6630-6660ft. Norton Sound, Bering Sea
Stratum typicum: Late Oligocene-early Miocene
Original diagnosis: Matsuoka and Bujak, 1988, p.69
Polygonal to elongate, bicavate intermediate proximochorate cyst. Endocyst ovoidal. Granular periphragm and smooth endophragm separated in the apical and antapical region by pericoels. Epicyst hemispherical and slightly smaller than hypocyst, with a poorly developed apical pericoel beneath the small apical horn which possesses a furcate process; hypocyst elongate hemispherical with moderately well-developed pericoel and two larger gonal processes. Parasutural septa low, slightly membranous near the furcate processes, and reflecting the paratabulation 3" (?), 6", 6c, 6""", 1p, xs. Processes mostly gonal, solid, and short with furcate distal extremities. Paracingulum relatively wide and almost circular; parasulcus poorly delimited by parasutural ridges, and almost straight. Archeopyle precingular, formed by the loss of paraplate 3".
Original description: Matsuoka and Bujak, 1988, p.70
The endocyst is ovoidal and the outline of the periphragm is elongate polygonal due to the presence of apical and antapical pericoels. The apical pericoel is small and cornucavate, whereas the antapical pericoel is larger and expanded. The apical horn is small, conical and typically branched. Two projections are present on the antapical area, and are formed by longer gonal processes. Most gonal processes have short solid stalks with trifurcate or sometimes bifurcate endings. The paracingulum is circular and moderately wide. The archeopyle is precingular and formed by the loss of paraplate 3". Dimension: Holotype; length of cyst 53µm, width 33µm, length of apical horn 6µm, height of parasuture 3Ám. Range; length of cyst 38-51µm, width 33-37µm, length of apical horn up to 7µm. Number of specimens measured: 5. Thecal affinities: Unknown; probably related to the Gonyaulacaceae based on its paratabulation and precingular archeopyle.
Matsuoka and Bujak, 1988, p.70:
The presence of gonal processes and bicavation indicates that this species is attributable to the genus Rottnestia. R. ovata differs from R. borussica (Eisenack) in possessing an antapical pericoel and in having a smaller apical horn. R. ovata is similar to Hystrichosphaeropsis arctia, H. variabile and Spiniferites ellipsoideus but is distinguished from the two species of Hystrichosphaeropsis in possessing gonal processes, and from S. ellipsoideus in having more conspicuous apical and antapical pericoels.