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Cladopyxidium halembayense
From Fensome et al., 2019:
Cladopyxidium? halmbayense Slimani, 1994, p.10–11, pl.1, figs.1–4,21–23. Holotype: Slimani, 1994, pl.1, figs.3–4,23. Questionable assignment: Slimani (1994, p.10). Age: late Maastrichtian.
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Cladopyxidium? halembayense sp. nov. (Pl.l, Fig.1-4,21-23) [translation pkb 2025]
Derivation of the name: From the type locality. Halembaye quarry, Maastricht region.
Holotvpe: Halembaye ech. 37, slide 1, coord. EF 032/1.
Paratvpe: Halembaye ech. 37, slide 7, coord. E.F. K32.
Type locality: Halembaye ex. 37.
Typical horizon: Upper Maastrichtian. (Vijlen Member).
Diagnosis: Small proximate acavate cyst, ovoid to subspheroidal in outline, with sides that converge slightly towards the apex. Its surface is microreticulated and provided with an equatorial transverse depression and a longitudinal depression which respectively indicate an unsegmented paracingulum and parasulcus. The cyst lacks a clear indication of paratabulation. The archaeopyle is atypically apical.
Dimensions: Holotype. length: 26 pm, width: 22 pm. Variations, length: 20 - 26 pm, width: 16-22 pm. Number of specimens measured: 15. Material: >30 specimens.
Description: The epicyst is smaller than the hypocyst. The autophragm (1 to 1.5 µm thick) is slightly scabrous; the microreticulum is more or less regular with meshes of 0.3 to 2.5 pm in diameter. The paracingulum is weakly laevogyre - it is 3 to 4 pm wide and delimited anteriorly and posteriorly by a higher reticulum. The parasulcus extends from the apex toward the antapex, widening slightly toward the antapex. The height and size of the reticulum meshes are very reduced at the level of the paracingulum and parasulcus. A clear indication of paratabulation is constantly missing. The archaeopyle (6 to 10 pm wide) has a subcircular to slightly angular outline. The operculum probably consists of two free or attached paraplates.
Note: Except for the lack of clear paratabulation indication, Cladopyxidium? halembayense sp. nov. presents almost all the characters which define the genus Cladopyxidium, the presence of a paracingulum and a parasulcus, although not segmented, allow us to provisionally attribute it rather to this genus than to Palaeostomocxstis DEILANDRE (1937b), emend . DEFLANDRE (1966) which is devoid of traces of parabulation and indications of the paracingulum and parasulcus.
Comparison: Cladopyxidium? haiembayense differs widely from Palaeostomocystis reticulata DEFLANDRE (1937b) (Pl. 7, Fig. 18, 47, 48) by its more regular reticulum and by the presence of a sulcal depression and a paracingulate depression. C. foveolatum MCMINN (1988) (Pl. 1, Fig. 5,6,33,34) and C. verrucosum MARHEINECKE (1992) (Pl. 1, Fig. 7) present a clear paratabulation. Fibradinium variculum STOVER and HELBY (1987d) also lacks signs of paratabulation and also presents a paracingulate depression as well as a sulcal depression, but its size is larger, its ectophragm is fibrous and its archaeopyle is wider.
Stratiaphic distribution: Halembaye: sample. 35 to 80, upper Maastrichtian. (Area to B. junior); Turnhout: -795.89 m, upper Maastrichtian.
Cladopyxidium? halmbayense Slimani, 1994, p.10–11, pl.1, figs.1–4,21–23. Holotype: Slimani, 1994, pl.1, figs.3–4,23. Questionable assignment: Slimani (1994, p.10). Age: late Maastrichtian.
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Cladopyxidium? halembayense sp. nov. (Pl.l, Fig.1-4,21-23) [translation pkb 2025]
Derivation of the name: From the type locality. Halembaye quarry, Maastricht region.
Holotvpe: Halembaye ech. 37, slide 1, coord. EF 032/1.
Paratvpe: Halembaye ech. 37, slide 7, coord. E.F. K32.
Type locality: Halembaye ex. 37.
Typical horizon: Upper Maastrichtian. (Vijlen Member).
Diagnosis: Small proximate acavate cyst, ovoid to subspheroidal in outline, with sides that converge slightly towards the apex. Its surface is microreticulated and provided with an equatorial transverse depression and a longitudinal depression which respectively indicate an unsegmented paracingulum and parasulcus. The cyst lacks a clear indication of paratabulation. The archaeopyle is atypically apical.
Dimensions: Holotype. length: 26 pm, width: 22 pm. Variations, length: 20 - 26 pm, width: 16-22 pm. Number of specimens measured: 15. Material: >30 specimens.
Description: The epicyst is smaller than the hypocyst. The autophragm (1 to 1.5 µm thick) is slightly scabrous; the microreticulum is more or less regular with meshes of 0.3 to 2.5 pm in diameter. The paracingulum is weakly laevogyre - it is 3 to 4 pm wide and delimited anteriorly and posteriorly by a higher reticulum. The parasulcus extends from the apex toward the antapex, widening slightly toward the antapex. The height and size of the reticulum meshes are very reduced at the level of the paracingulum and parasulcus. A clear indication of paratabulation is constantly missing. The archaeopyle (6 to 10 pm wide) has a subcircular to slightly angular outline. The operculum probably consists of two free or attached paraplates.
Note: Except for the lack of clear paratabulation indication, Cladopyxidium? halembayense sp. nov. presents almost all the characters which define the genus Cladopyxidium, the presence of a paracingulum and a parasulcus, although not segmented, allow us to provisionally attribute it rather to this genus than to Palaeostomocxstis DEILANDRE (1937b), emend . DEFLANDRE (1966) which is devoid of traces of parabulation and indications of the paracingulum and parasulcus.
Comparison: Cladopyxidium? haiembayense differs widely from Palaeostomocystis reticulata DEFLANDRE (1937b) (Pl. 7, Fig. 18, 47, 48) by its more regular reticulum and by the presence of a sulcal depression and a paracingulate depression. C. foveolatum MCMINN (1988) (Pl. 1, Fig. 5,6,33,34) and C. verrucosum MARHEINECKE (1992) (Pl. 1, Fig. 7) present a clear paratabulation. Fibradinium variculum STOVER and HELBY (1987d) also lacks signs of paratabulation and also presents a paracingulate depression as well as a sulcal depression, but its size is larger, its ectophragm is fibrous and its archaeopyle is wider.
Stratiaphic distribution: Halembaye: sample. 35 to 80, upper Maastrichtian. (Area to B. junior); Turnhout: -795.89 m, upper Maastrichtian.