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Cladopyxidium paucireticulatum
From Fensome et al., 2019:
Cladopyxidium paucireticulatum Slimani, 1994, p.11–12, pl.1, figs.14–15,28–30. Holotype: Slimani, 1994, pl.1, figs.14–15,28–29. Age: early–late Maastrichtian.
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Derivation of the name: Latin: pauci, little; reticulatus, reticulate; reference to the imperfect intratabular reticulum.
Holotvpe: Halembaye ech. 35, slide 2, coord. E.F. X43/4.
Type locality: Halembaye ex. 35.
Typical horizon: Upper Maastrichtian. (Vijlen Member).
Synonymy: 71983a: Cladopyxidium sp. - FOLICHER, pl. 7, fig. 17-18.
Diagnosis: Small Cladopyxidium cyst, ellipsoidal to subspheroidal with a hemispheroidal hypocyst larger than the epicyst. It is characterized by the presence of a poorly developed intratabular reticulum. Paratabulation is indicated by low parasutural ridges and corresponds to the formula: 4', 3a, 6", 6c, 6"', lp. 1"" . 5s.
Dimensions: Holotype: length: 26 pm, width: 24 pm. Variations: length: 20 - 26 pm. width: 14-24 pm. Number of specimens measured: 15. Material: >25 specimens.
Description: The autophragm is finely shabby (1 to 1.5 pm thick) and the parasutural ridges it bears are membranous and low (1-2 pm high). The combination of irregular accessory ridges, vermicules and granules gives rise to a reticulum which completely or partially covers the intratabular areas. The parasulcus is divided into four small quadrangular anterior paraplates and a larger pentagonal posterior paraplate. The segmented paracingulum (4 pm wide) is laevorotatory. The archaeopyle (6 to 8 pm wide) is atypical apical, subcircular with a slight thickening at the edge; the operculum is probably formed by two small apical paraplates 2' and 3', free or attached, the paraplates 1 and 4' are not part of the archaeopyle.
Comparison: Specimens of Cladopxzidium sp. figured by FOUCHER (1983a: pl. 7, fig. 17-18) are probably close to Cladopyxidiumpaucireticulatum sp. nov., but their paratabulation is obscure. C. foveolatum MCMINN (1988) emend. MARHEINECKE (1992) can also present an intratabular reticulum, but the cyst is larger in size, with higher parasutural ridges, and a foveated autophragm. Pcdacostomocystis reticulata DEFLANDRE (1937b) lacks signs of paratabulation and has a more perfect reticulum than that of C. paucireticulatum. Cladopyxidium vclaium MARHEINECKE (1992) (Pl. 1, Fig. 8-10,38-40) and C. septocrispum BELOW (1987b) (PL. 1, Fig. 11-13) differ respectively mainly by the presence of hypocystal ridges more developed and by the absence of intratabular reticulum. Microdinium reticulation VOZZHENNIKOVA (1967) also presents an intratabular reticulum but differs from C. paucireticulatum mainly by its larger size, its shape and its wider archaeopyle, combining the apical and intercalary paraplates.
Stratigraphic distribution: Halembaye: sample. 35 to 57, upper Maastrichtian. (Zone to B. junior); Turnhout: -874 to -807.90 m, Lower Maastrichtian - Upper Maastrichtian.
Cladopyxidium paucireticulatum Slimani, 1994, p.11–12, pl.1, figs.14–15,28–30. Holotype: Slimani, 1994, pl.1, figs.14–15,28–29. Age: early–late Maastrichtian.
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Derivation of the name: Latin: pauci, little; reticulatus, reticulate; reference to the imperfect intratabular reticulum.
Holotvpe: Halembaye ech. 35, slide 2, coord. E.F. X43/4.
Type locality: Halembaye ex. 35.
Typical horizon: Upper Maastrichtian. (Vijlen Member).
Synonymy: 71983a: Cladopyxidium sp. - FOLICHER, pl. 7, fig. 17-18.
Diagnosis: Small Cladopyxidium cyst, ellipsoidal to subspheroidal with a hemispheroidal hypocyst larger than the epicyst. It is characterized by the presence of a poorly developed intratabular reticulum. Paratabulation is indicated by low parasutural ridges and corresponds to the formula: 4', 3a, 6", 6c, 6"', lp. 1"" . 5s.
Dimensions: Holotype: length: 26 pm, width: 24 pm. Variations: length: 20 - 26 pm. width: 14-24 pm. Number of specimens measured: 15. Material: >25 specimens.
Description: The autophragm is finely shabby (1 to 1.5 pm thick) and the parasutural ridges it bears are membranous and low (1-2 pm high). The combination of irregular accessory ridges, vermicules and granules gives rise to a reticulum which completely or partially covers the intratabular areas. The parasulcus is divided into four small quadrangular anterior paraplates and a larger pentagonal posterior paraplate. The segmented paracingulum (4 pm wide) is laevorotatory. The archaeopyle (6 to 8 pm wide) is atypical apical, subcircular with a slight thickening at the edge; the operculum is probably formed by two small apical paraplates 2' and 3', free or attached, the paraplates 1 and 4' are not part of the archaeopyle.
Comparison: Specimens of Cladopxzidium sp. figured by FOUCHER (1983a: pl. 7, fig. 17-18) are probably close to Cladopyxidiumpaucireticulatum sp. nov., but their paratabulation is obscure. C. foveolatum MCMINN (1988) emend. MARHEINECKE (1992) can also present an intratabular reticulum, but the cyst is larger in size, with higher parasutural ridges, and a foveated autophragm. Pcdacostomocystis reticulata DEFLANDRE (1937b) lacks signs of paratabulation and has a more perfect reticulum than that of C. paucireticulatum. Cladopyxidium vclaium MARHEINECKE (1992) (Pl. 1, Fig. 8-10,38-40) and C. septocrispum BELOW (1987b) (PL. 1, Fig. 11-13) differ respectively mainly by the presence of hypocystal ridges more developed and by the absence of intratabular reticulum. Microdinium reticulation VOZZHENNIKOVA (1967) also presents an intratabular reticulum but differs from C. paucireticulatum mainly by its larger size, its shape and its wider archaeopyle, combining the apical and intercalary paraplates.
Stratigraphic distribution: Halembaye: sample. 35 to 57, upper Maastrichtian. (Zone to B. junior); Turnhout: -874 to -807.90 m, Lower Maastrichtian - Upper Maastrichtian.