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Stephodinium spinosum
From Fensome et al., 2019:
Stephodinium ?spinosum Slimani, 1996, p.379–380, pl.1, figs.M–R ex Slimani, 2001b, p.8–9, pl.3, figs.12–17. Holotype: Slimani, 1996, pl.1, figs.M–N; Slimani, 2001b, pl.3, figs.12–13. Questionable assignment: Slimani (1996, p.379; 2001b, p.8). This name was not validly published in Slimani (1996) since no English or Latin description or diagnosis was provided. Age: early–late Campanian.
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Original description (Slimani, 1996) Not yet translated from French.
Derivation of the name. Processes that adorn the central body.
Occurrence: Turnhout -987 to -933 m (Lower to Upper Campanian).
Description: Cavate cyst with an elongated ellipsoidal endocyst extending apex-to-antapex. The periphragm is smooth to dotted, closely adhered to the endocyst at the apical and antapical poles and over a narrow area of the ventral surface, and separates from it in the cingulate region, forming a broad equatorial pericoel interrupted ventrally. The areas where the periphragm and endocyst are adhered bear fine, flexuous, solid and/or hollow processes, distally acuminate. Paratabulation is absent. The archeopyle is generally invisible except in some specimens where fissures suggest an apparently precingular archeopyle.
Dimensions. Central body length: holotype, 24 µm; other specimens, 24–32 µm. Central body width: holotype, 18 µm; other specimens, 15–20 µm. Equatorial pericoel height: holotype, 8 µm; other specimens, 6–10 µm. Equatorial pericoel width: holotype, 8 µm; other specimens, 7–10 µm. Process lengths: 4–9 µm. Number of specimens measured: 15.
Remarks. Stephodinium spinosum is a species whose morphological characteristics largely correspond to the definition of the genus Stephodinium, but it lacks evidence of paratabulation. It is for this reason that this new species is provisionally placed in the genus Stephodinium. It is characterized by its small size and the presence of processes on both the apical and antapical poles. Stephodinium pellucidum Deflandre (1943) and Stephodinium parvum De Conick (1986) are also small and lack evidence of paratabulation, but they do not bear processis and their pericoel is continuous ventrally.
Stephodinium ?spinosum Slimani, 1996, p.379–380, pl.1, figs.M–R ex Slimani, 2001b, p.8–9, pl.3, figs.12–17. Holotype: Slimani, 1996, pl.1, figs.M–N; Slimani, 2001b, pl.3, figs.12–13. Questionable assignment: Slimani (1996, p.379; 2001b, p.8). This name was not validly published in Slimani (1996) since no English or Latin description or diagnosis was provided. Age: early–late Campanian.
---------------------------------------------------------------------------------------------------
Original description (Slimani, 1996) Not yet translated from French.
Derivation of the name. Processes that adorn the central body.
Occurrence: Turnhout -987 to -933 m (Lower to Upper Campanian).
Description: Cavate cyst with an elongated ellipsoidal endocyst extending apex-to-antapex. The periphragm is smooth to dotted, closely adhered to the endocyst at the apical and antapical poles and over a narrow area of the ventral surface, and separates from it in the cingulate region, forming a broad equatorial pericoel interrupted ventrally. The areas where the periphragm and endocyst are adhered bear fine, flexuous, solid and/or hollow processes, distally acuminate. Paratabulation is absent. The archeopyle is generally invisible except in some specimens where fissures suggest an apparently precingular archeopyle.
Dimensions. Central body length: holotype, 24 µm; other specimens, 24–32 µm. Central body width: holotype, 18 µm; other specimens, 15–20 µm. Equatorial pericoel height: holotype, 8 µm; other specimens, 6–10 µm. Equatorial pericoel width: holotype, 8 µm; other specimens, 7–10 µm. Process lengths: 4–9 µm. Number of specimens measured: 15.
Remarks. Stephodinium spinosum is a species whose morphological characteristics largely correspond to the definition of the genus Stephodinium, but it lacks evidence of paratabulation. It is for this reason that this new species is provisionally placed in the genus Stephodinium. It is characterized by its small size and the presence of processes on both the apical and antapical poles. Stephodinium pellucidum Deflandre (1943) and Stephodinium parvum De Conick (1986) are also small and lack evidence of paratabulation, but they do not bear processis and their pericoel is continuous ventrally.