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Tenua rioultii
Tenua rioultii (Sarjeant, 1968) Davey, 1978; Emendation: Courtinat, 1989, p.192, as Sentusidinium rioultii.
Combination illegitimate since the generic name Tenua Davey, 1978, is illegitimate.
Now Sentusidinium. Originally Tenua Eisenack, 1958, subsequently Batiacasphaera, thirdly (and now) Sentusidinium, fourthly Tenua Davey, 1978 (combination illegitimate).
Holotype: Sarjeant, 1968, pl.1, fig.22; pl.2, fig.1
Paratype: Sarjeant, 1968
Locus typicus: Marnes de Dives, Falaise des Vaches Noires, Villers-sur-Mer, France
Stratum typicum: latest Callovian
Translation Courtinat, 1989: LPP
Original diagnosis: Sarjeant, 1968, p.231: Tenua rioultii
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.
Emended diagnosis: Courtinat, 1989, p.192
Subspherical apteate cyst with an autophragm only, with sutural and rare intratabular processes. These processes are simple or bifurcate with pointed, capitate or again trifurcate tips. The paracingulum and parasulcus lack processes. The gonyaulacacean type paratabulation has the same formula as the genus. The archaeopyle is apical; the accessory archaeopyle sutures are ill-developed. The opeculum is free multiplated.
Combination illegitimate since the generic name Tenua Davey, 1978, is illegitimate.
Now Sentusidinium. Originally Tenua Eisenack, 1958, subsequently Batiacasphaera, thirdly (and now) Sentusidinium, fourthly Tenua Davey, 1978 (combination illegitimate).
Holotype: Sarjeant, 1968, pl.1, fig.22; pl.2, fig.1
Paratype: Sarjeant, 1968
Locus typicus: Marnes de Dives, Falaise des Vaches Noires, Villers-sur-Mer, France
Stratum typicum: latest Callovian
Translation Courtinat, 1989: LPP
Original diagnosis: Sarjeant, 1968, p.231: Tenua rioultii
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.
Emended diagnosis: Courtinat, 1989, p.192
Subspherical apteate cyst with an autophragm only, with sutural and rare intratabular processes. These processes are simple or bifurcate with pointed, capitate or again trifurcate tips. The paracingulum and parasulcus lack processes. The gonyaulacacean type paratabulation has the same formula as the genus. The archaeopyle is apical; the accessory archaeopyle sutures are ill-developed. The opeculum is free multiplated.