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Lejeunecysta communis
Lejeunecysta communis Biffi and Grignani, 1983
Holotype: Biffi and Grignani, 1983, pl.1, fig.5
Paratypes: Biffi and Grignani, 1983
Locus typicus: Niger Delta, Nigeria
Stratum typicum: Oligocene
Original diagnosis: Biffi and Grignani, 1983, p. 131-132
Autocyst proximate, peridinioid, compressed dorsoventrally with pentagonal ambitus. Epicyst and hypocyst lengths approximately equal. Epicyst conical with straight sides; apex with distinct, small, rounded, solid horn. Hypocyst trapezoidal with slightly concave sides. Two antapical horns long, conical, ending with sharp, solid spine. Antapical depression prominent. Autophragm laevigate. Paracingulum continuous, marked by transverse folds. Hexa archeopyle formed by loss of intercalary 2a and symmetrically situated on middorsal line. Lower margin of archeopyle sometimes near paracingulum.
Dimensions: Holotype: autocyst length 81 Ám, breadth 80 Ám. Other specimens: autocyst length 60-95 Ám, breadth 50-85 Ám. Number of specimens measured, 20.
Affinities:
Biffi and Grignani, 1983, p. 132: Lejeunecysta communis differs from L. fallax in having a thinner autocyst wall, hypocyst sides slightly concave rather than straight, a distinct apical horn, and the epicyst and hypocyst length approximately equal. It differs from the holotype of L. diversiforma in having a distinct apical horn and straight rather than convex epicyst sides. Furthermore, L. communis never has pericoels. The single specimen figured by Benedek, 1972, as Lejeunia sp. (pl. 6, fig. 2) seems to belong to L. communis, even if the presence of an apical horn is not mentioned.
Holotype: Biffi and Grignani, 1983, pl.1, fig.5
Paratypes: Biffi and Grignani, 1983
Locus typicus: Niger Delta, Nigeria
Stratum typicum: Oligocene
Original diagnosis: Biffi and Grignani, 1983, p. 131-132
Autocyst proximate, peridinioid, compressed dorsoventrally with pentagonal ambitus. Epicyst and hypocyst lengths approximately equal. Epicyst conical with straight sides; apex with distinct, small, rounded, solid horn. Hypocyst trapezoidal with slightly concave sides. Two antapical horns long, conical, ending with sharp, solid spine. Antapical depression prominent. Autophragm laevigate. Paracingulum continuous, marked by transverse folds. Hexa archeopyle formed by loss of intercalary 2a and symmetrically situated on middorsal line. Lower margin of archeopyle sometimes near paracingulum.
Dimensions: Holotype: autocyst length 81 Ám, breadth 80 Ám. Other specimens: autocyst length 60-95 Ám, breadth 50-85 Ám. Number of specimens measured, 20.
Affinities:
Biffi and Grignani, 1983, p. 132: Lejeunecysta communis differs from L. fallax in having a thinner autocyst wall, hypocyst sides slightly concave rather than straight, a distinct apical horn, and the epicyst and hypocyst length approximately equal. It differs from the holotype of L. diversiforma in having a distinct apical horn and straight rather than convex epicyst sides. Furthermore, L. communis never has pericoels. The single specimen figured by Benedek, 1972, as Lejeunia sp. (pl. 6, fig. 2) seems to belong to L. communis, even if the presence of an apical horn is not mentioned.