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Pervosphaeridium tubuloaculeatum
From Fensome et al., 2019:
Pervosphaeridium tubuloaculeatum Slimani, 1994, p.82–83, pl.12, figs.24–28. Holotype: Slimani, 1994, pl.12, figs.27–28. Age: early Maastrichtian–earliest Danian.
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Original description (Slimani, 1994): Translation PKB 2025:
Pervosphaeridium tubuloaculeatum sp. Nov. (PI.12, Fig.24-28)
Derivation of the name: Latin: tubus, tube; aculeatus, aculeate; reference to tubiform processes with aculeate distal end.
Holotvpe: Halembaye ech. 35, preparation 4, coord. E.F. H31/2.
Type locality: Halembaye ex. 35.
Typical horizon: Upper Maastrichtian. (Member of Vijlen).
Diagnosis: Choral cyst; the central body is ovoidal to subspheroidal, slightly granulated to slightly fibrous and characterized by the presence of a small apical bump. It bears numerous uniform, simple, tubular intratabular processes that flare at their distal end and terminate in an aculeate margin. The length of the processes is around 50 and 60% of the diameter of the central body. The archaeopyle is precingulate of type 2P, the operculum consists of two free pieces that have sometimes fallen inside the cyst.
Dimensions: Holotype. Maximum diameter of the central body: 30 µm, total diameter: 64 µm. Variations: Maximum diameter of the central body: 26-32 µm, total diameter: 60-70 µm. Process length: 12-20 µm. Number of specimens measured: 15.
Material: > 90 specimens.
Description: The smooth endophragm and the slightly granulated to slightly fibrous periphragm are in close contact between the process bases and form a rigid autophragm about 2 µm thick. The small apical bump, which is constantly present, is about 4 µm in size and allows the orientation of the cyst. The processes are rigid, smooth to scabrous, rarely striated at the base and open distally; they are broad at their base, then narrow slightly towards the distal end, which is slightly flared. The number of processes varies between 2 and 4 per plate. No distinct apical or antapical processes are observed. An alignment of processes is sometimes observed on the paracingulum. The archaeopyle also allows the orientation of the cyst.
Comparison: This species differs from other published species of the genus Pervosphaeridium by the presence of an apical bump and by its tubiform, hollow, and aculeate processes. The specimens named Pervosphaeridium elegans by LOUWYE in his 1991 doctoral work also have tubiform processes, but are distinguished from the studied species by the absence of an apical bump, by its slightly larger size, its more numerous, longer, and slender processes, of a different shape, and also by the ornamentation of the central body. Raetiaediniumpumiatum sp. nov. (in this work) has a cyst of the same size, and bears the same type of process but wider and numbering one per plate, its paracingulate, parasulcal, and apical processes being a little thinner.
Locality: Halembaye: ex. 35 to 61, upper Maastrichtian. (Zone to B. junior). Turnhout: -864.60 to -759.89 m, lower Maastrichtian. - early Danian.
Pervosphaeridium tubuloaculeatum Slimani, 1994, p.82–83, pl.12, figs.24–28. Holotype: Slimani, 1994, pl.12, figs.27–28. Age: early Maastrichtian–earliest Danian.
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Original description (Slimani, 1994): Translation PKB 2025:
Pervosphaeridium tubuloaculeatum sp. Nov. (PI.12, Fig.24-28)
Derivation of the name: Latin: tubus, tube; aculeatus, aculeate; reference to tubiform processes with aculeate distal end.
Holotvpe: Halembaye ech. 35, preparation 4, coord. E.F. H31/2.
Type locality: Halembaye ex. 35.
Typical horizon: Upper Maastrichtian. (Member of Vijlen).
Diagnosis: Choral cyst; the central body is ovoidal to subspheroidal, slightly granulated to slightly fibrous and characterized by the presence of a small apical bump. It bears numerous uniform, simple, tubular intratabular processes that flare at their distal end and terminate in an aculeate margin. The length of the processes is around 50 and 60% of the diameter of the central body. The archaeopyle is precingulate of type 2P, the operculum consists of two free pieces that have sometimes fallen inside the cyst.
Dimensions: Holotype. Maximum diameter of the central body: 30 µm, total diameter: 64 µm. Variations: Maximum diameter of the central body: 26-32 µm, total diameter: 60-70 µm. Process length: 12-20 µm. Number of specimens measured: 15.
Material: > 90 specimens.
Description: The smooth endophragm and the slightly granulated to slightly fibrous periphragm are in close contact between the process bases and form a rigid autophragm about 2 µm thick. The small apical bump, which is constantly present, is about 4 µm in size and allows the orientation of the cyst. The processes are rigid, smooth to scabrous, rarely striated at the base and open distally; they are broad at their base, then narrow slightly towards the distal end, which is slightly flared. The number of processes varies between 2 and 4 per plate. No distinct apical or antapical processes are observed. An alignment of processes is sometimes observed on the paracingulum. The archaeopyle also allows the orientation of the cyst.
Comparison: This species differs from other published species of the genus Pervosphaeridium by the presence of an apical bump and by its tubiform, hollow, and aculeate processes. The specimens named Pervosphaeridium elegans by LOUWYE in his 1991 doctoral work also have tubiform processes, but are distinguished from the studied species by the absence of an apical bump, by its slightly larger size, its more numerous, longer, and slender processes, of a different shape, and also by the ornamentation of the central body. Raetiaediniumpumiatum sp. nov. (in this work) has a cyst of the same size, and bears the same type of process but wider and numbering one per plate, its paracingulate, parasulcal, and apical processes being a little thinner.
Locality: Halembaye: ex. 35 to 61, upper Maastrichtian. (Zone to B. junior). Turnhout: -864.60 to -759.89 m, lower Maastrichtian. - early Danian.