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Tenua rioultii
Tenua rioultii Sarjeant, 1968, p.231, pl.1, figs.12,22; pl.2, figs.1–2,4. Emendation: Courtinat, 1989, p.192, as Sentusidinium rioultii.
Now Sentusidinium. Originally Tenua Eisenack, 1958, subsequently Batiacasphaera, thirdly (and now) Sentusidinium; see also Tenua Davey, 1978 (combination illegitimate).
Holotype: Sarjeant, 1968, pl.1, fig.22; pl.2, fig.1; Eisenack and Kjellström, 1972, figure to left — p.1043; Fensome et al., 1995, fig.1 — p.1743; Fauconnier and Masure, 2004, pl.70, fig.4.
Paratype: Sarjeant, 1968
Locus typicus: Marnes de Dives, Falaise des Vaches Noires, Villers-sur-Mer, France
Stratum typicum: Late Callovian
Original diagnosis: Sarjeant, 1968, p.231
Shell broadly ovoidal, with a pronouncedly granular surface. Spines numerous (around 200), well spaced, varying in length but always short (ranging in length between one-fifth and one ninth of the shell breadth). Spines highly variable in thickness and in form: they may be capitate, bifurcate or trifurcate, with branches of equal or unequal length which may themselves bifurcate. Cingulum and sulcus lack spines; the cingulum is relatively narrow, the sulcus broader. Apical archaeopyle generally or consistently developed, with a pronouncedly scalloped margin.
Dimensions: Holotype: overall length (apex lacking) 48 µm, breadth 50.5 µm; shell length 45 µm, breadth 45 µm. Paratype: overall length (apex lacking) 61.5 µm, breadth 69 µm; shell length 53 µm, breadth 59 µm. Range: overall length (apices lacking) 48-62 µm, breadth 50.5-69 µm, shell length 45-57 µm, breadth 44. 5-57 µm.
Now Sentusidinium. Originally Tenua Eisenack, 1958, subsequently Batiacasphaera, thirdly (and now) Sentusidinium; see also Tenua Davey, 1978 (combination illegitimate).
Holotype: Sarjeant, 1968, pl.1, fig.22; pl.2, fig.1; Eisenack and Kjellström, 1972, figure to left — p.1043; Fensome et al., 1995, fig.1 — p.1743; Fauconnier and Masure, 2004, pl.70, fig.4.
Paratype: Sarjeant, 1968
Locus typicus: Marnes de Dives, Falaise des Vaches Noires, Villers-sur-Mer, France
Stratum typicum: Late Callovian
Original diagnosis: Sarjeant, 1968, p.231
Shell broadly ovoidal, with a pronouncedly granular surface. Spines numerous (around 200), well spaced, varying in length but always short (ranging in length between one-fifth and one ninth of the shell breadth). Spines highly variable in thickness and in form: they may be capitate, bifurcate or trifurcate, with branches of equal or unequal length which may themselves bifurcate. Cingulum and sulcus lack spines; the cingulum is relatively narrow, the sulcus broader. Apical archaeopyle generally or consistently developed, with a pronouncedly scalloped margin.
Dimensions: Holotype: overall length (apex lacking) 48 µm, breadth 50.5 µm; shell length 45 µm, breadth 45 µm. Paratype: overall length (apex lacking) 61.5 µm, breadth 69 µm; shell length 53 µm, breadth 59 µm. Range: overall length (apices lacking) 48-62 µm, breadth 50.5-69 µm, shell length 45-57 µm, breadth 44. 5-57 µm.