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Lejeunecysta convexa
Lejeunecysta convexa Matsuoka and Bujak, 1988
Holotype: Matsuoka and Bujak, 1988, pl.6, fig.2, text-fig.11A
Paratype: Matsuoka and Bujak, 1988
Locus typicus: COST No. 2 Well, St. George Basin, Bering Sea
Stratum typicum: Late Oligocene-Early Miocene
Original diagnosis: Matsuoka and Bujak, 1988, p.57
Intermediate to small proximate pentagonal cyst compressed dorso-ventrally. Epicyst longer than hypocyst, conical with concave to straight sides in dorso-ventral view with two small acuminate antapical horns. Cyst wall comprising an autophragm which is brownish-pigmented and smooth without ornament. Paracingulum well-developed; parasulcus shallow. Paratabulation absent except for archeopyle and paracingulum. Archeopyle simple intercalary, formed by the loss of paraplate 2a.
Original description: Matsuoka and Bujak, 1988, p.57
The sides of the epicyst vary in dorso-ventral view from straight to convex and those of the hypocyst from straight to concave. The cyst wall is pigmented brown, non-fluorescent and consists of an autophragm with a smooth surface. Two conspicuous antapical horns diverge slightly. The paracingulum is continuous but weakly marked by folds. The parasulcus is represented by a shallow indentation. The intercalary archeopyle is trapezoidal and is formed by the loss of paraplate 2a.
Dimensions: Holotype; length of cyst 59 Ám, width 55 Ám length of antapical horns 8 Ám. Range; length of cyst 46-59 Ám width 32-55 Ám. Number of specimens measured: 5.
Thecal affinities: Unknown; possibly a cyst of t.he subgenus Protoperidinium based on its brownish single cyst wall and simple intercalary archeopyle formed by the loss of paraplate 2a.
Affinities:
Matsuoka and Bujak, 1988, p.58: Lejeunecysta conuexa is similar to L. pulchra Biffi and Grignani and Lejeunea sp. B of Bradford, 1977, in its elongate pentagonal cyst body. The new species differs from L. pulchra in lacking a conspicuous apical horn and weak indentation between the two antapical horns, and in possessing a clearly marked paracingulum. It differs from Lejeunecysta sp. B of Bradford, 1977, in possessing two well-developed antapical horns.
Holotype: Matsuoka and Bujak, 1988, pl.6, fig.2, text-fig.11A
Paratype: Matsuoka and Bujak, 1988
Locus typicus: COST No. 2 Well, St. George Basin, Bering Sea
Stratum typicum: Late Oligocene-Early Miocene
Original diagnosis: Matsuoka and Bujak, 1988, p.57
Intermediate to small proximate pentagonal cyst compressed dorso-ventrally. Epicyst longer than hypocyst, conical with concave to straight sides in dorso-ventral view with two small acuminate antapical horns. Cyst wall comprising an autophragm which is brownish-pigmented and smooth without ornament. Paracingulum well-developed; parasulcus shallow. Paratabulation absent except for archeopyle and paracingulum. Archeopyle simple intercalary, formed by the loss of paraplate 2a.
Original description: Matsuoka and Bujak, 1988, p.57
The sides of the epicyst vary in dorso-ventral view from straight to convex and those of the hypocyst from straight to concave. The cyst wall is pigmented brown, non-fluorescent and consists of an autophragm with a smooth surface. Two conspicuous antapical horns diverge slightly. The paracingulum is continuous but weakly marked by folds. The parasulcus is represented by a shallow indentation. The intercalary archeopyle is trapezoidal and is formed by the loss of paraplate 2a.
Dimensions: Holotype; length of cyst 59 Ám, width 55 Ám length of antapical horns 8 Ám. Range; length of cyst 46-59 Ám width 32-55 Ám. Number of specimens measured: 5.
Thecal affinities: Unknown; possibly a cyst of t.he subgenus Protoperidinium based on its brownish single cyst wall and simple intercalary archeopyle formed by the loss of paraplate 2a.
Affinities:
Matsuoka and Bujak, 1988, p.58: Lejeunecysta conuexa is similar to L. pulchra Biffi and Grignani and Lejeunea sp. B of Bradford, 1977, in its elongate pentagonal cyst body. The new species differs from L. pulchra in lacking a conspicuous apical horn and weak indentation between the two antapical horns, and in possessing a clearly marked paracingulum. It differs from Lejeunecysta sp. B of Bradford, 1977, in possessing two well-developed antapical horns.