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Raetiaedinium laevigatum
From Fensome et al., 2019:
Raetiaedinium laevigatum Slimani, 1994, p.86–87, pl.12, figs.1–3. Holotype: Slimani, 1994, pl.12, figs.1–2. Age: early Campanian–earliest Danian.
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Original description (Slimani, 1994) Not yet translated from French
Name derivation: Latin: laevigatus, smooth; referring to the periphragm and smooth processes.
Holotype: Turnhout -933 m, preparation 9, coordinates E.F. N29.3.
Type locality: Turnhout -933 m
Type horizon: Upper Campanian.
Diagnosis: Chorata cyst. The central body is spheroidal to subspheroidal with a generally smooth wall. The processes are tubular and closed distally; there is one per plate, broad proximally, and gradually tapering towards their distal end, which is flared and terminates in a dry margin. They reach a length of 2/3 to 1/1 of the diameter of the central body and a width that is almost uniform within the same individual. The paratabulation is of the gonyaulacoid type: 4', 6", 6c, 6", 1p, 1", 5s. The archeopyl is precingular of the 2P(3'+4') type; the operculum is composed of two disjointed and free paraplates.
Dimensions: Holotype: maximum diameter of the central body: 30 µm. Process length: 20–26 µm. Variations: central body length: 32–40 µm, width: 30–40 µm. Process length: 22–40 µm. Number of specimens measured: 15. Material: 150 specimens.
Description: The endophragm and periphragm are smooth to very slightly scabrous and in contact in very narrow areas located between the bases of the processes. The periphragm is convex into a small (2–4 µm long) apical protrusion in the form of a nipple, very rarely surmounted by two filiform projections (approximately 6 µm long). The processes have smooth or slightly scabrous walls. They are long, slender, rigid, and occupy a maximum of the intratabular surface proximally; they are closed distally or have perforations 0.5 to 2 µm in diameter. The apical and sulcal processes are slightly thinner than the others. Slight intraspecific variation in the width of the processes is observed.
Comparison: Raetiaedinium laevigatum sp. nov. and Kleithriasphaeridium loffrense Davey and Verdier (1976) are comparable in the general appearance of their cysts, but are distinguished primarily by their type of archaeopyl, which is 2P and P, respectively. Hystrichosphaeridium sp. 1 of Schumacker-Lambry in Streel et al. (1977: fig. 25a, pl. 3, fig. 20), found in the Upper Campanian and Upper Maastrichtian of northeastern Belgium, is very similar to our species.
Locality: Beutenaken: specimens 1 to 19, Halembaye: specimens 2 to 80; Lower Campanian - Upper Maastrichtian (G. quadrata Zone - B. junior Zone). Turnhout: -978 to -759.89 m, Upper Campanian. - early Danian.
Raetiaedinium laevigatum Slimani, 1994, p.86–87, pl.12, figs.1–3. Holotype: Slimani, 1994, pl.12, figs.1–2. Age: early Campanian–earliest Danian.
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Original description (Slimani, 1994) Not yet translated from French
Name derivation: Latin: laevigatus, smooth; referring to the periphragm and smooth processes.
Holotype: Turnhout -933 m, preparation 9, coordinates E.F. N29.3.
Type locality: Turnhout -933 m
Type horizon: Upper Campanian.
Diagnosis: Chorata cyst. The central body is spheroidal to subspheroidal with a generally smooth wall. The processes are tubular and closed distally; there is one per plate, broad proximally, and gradually tapering towards their distal end, which is flared and terminates in a dry margin. They reach a length of 2/3 to 1/1 of the diameter of the central body and a width that is almost uniform within the same individual. The paratabulation is of the gonyaulacoid type: 4', 6", 6c, 6", 1p, 1", 5s. The archeopyl is precingular of the 2P(3'+4') type; the operculum is composed of two disjointed and free paraplates.
Dimensions: Holotype: maximum diameter of the central body: 30 µm. Process length: 20–26 µm. Variations: central body length: 32–40 µm, width: 30–40 µm. Process length: 22–40 µm. Number of specimens measured: 15. Material: 150 specimens.
Description: The endophragm and periphragm are smooth to very slightly scabrous and in contact in very narrow areas located between the bases of the processes. The periphragm is convex into a small (2–4 µm long) apical protrusion in the form of a nipple, very rarely surmounted by two filiform projections (approximately 6 µm long). The processes have smooth or slightly scabrous walls. They are long, slender, rigid, and occupy a maximum of the intratabular surface proximally; they are closed distally or have perforations 0.5 to 2 µm in diameter. The apical and sulcal processes are slightly thinner than the others. Slight intraspecific variation in the width of the processes is observed.
Comparison: Raetiaedinium laevigatum sp. nov. and Kleithriasphaeridium loffrense Davey and Verdier (1976) are comparable in the general appearance of their cysts, but are distinguished primarily by their type of archaeopyl, which is 2P and P, respectively. Hystrichosphaeridium sp. 1 of Schumacker-Lambry in Streel et al. (1977: fig. 25a, pl. 3, fig. 20), found in the Upper Campanian and Upper Maastrichtian of northeastern Belgium, is very similar to our species.
Locality: Beutenaken: specimens 1 to 19, Halembaye: specimens 2 to 80; Lower Campanian - Upper Maastrichtian (G. quadrata Zone - B. junior Zone). Turnhout: -978 to -759.89 m, Upper Campanian. - early Danian.