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Cribroperidinium murochoratum
From Fensome et al., 2019:
Cribroperidinium? murochoratum Dürr, 1987, p.72–74, fig.2; fig.4, nos.1–2; fig.5, nos.6–7; fig.6, nos.4,6–8. Holotype: Dürr, 1987, fig.4, nos.1–2. Questionable assignment: Dürr (1987, p.72). Age: middle Kimmeridgian.
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Original description: [Dürr, 1987] (translated from German):
Cribroperidinium murochoratum n. sp.
Fig. 2; Fig. 4, Figs. 1, 2, Fig. 5. Fig. 6, 7; Fig. 6, Figs. 4, 6-8
Holotype: Specimen GPIT 1663-1; Fig. 4, Figs. 1-2.
Paratypoids: Specimens GPIT 1663/2, 1663/12 Nos. 18, 23, 29.
Fig. 5, Figs. 6-7; Fig. 6, Figs. 4, 6-8.
Typical stratum: White Jurassic S (mutabilis zone), sample GE-12, from the uppermost part of the lowest marl band.
Typical locus: Quarry of the gravel works east of Genkingen, TK 25:7521 - Reutlingen; Coordinates: r^(35)15300/h^(53)64150.
Derivation: murochorate (after EVITT, 1985) Parasutures with septa, referring to the ornamentation of the surface.
Diagnosis: A species of the genus Cribroperidinium with high parasutural and additional penitabular and radial septa. Paratabulation: 6", 5"', 4', 6c, 6-7s, 1p, 1"", flagellar field.
Description:
The cyst is ovoid to pentagonal with high parasutural, penitabular, and radial septa. It shows the following paratabulation pattern: 6", 5"', 4', 6c, 6-7s, 1p, 1"", flagellar field. Archaeopyle 3".
Plate sp is sickle-shaped and, shifted to the right, extends almost to the paracingulum.
Plate ssa is probably homologous to the 1'" in other Cribroperidinium species; however, it has migrated into the sulcal field and no longer has a direct connection to the paracingulum. This indicates that Cribroperidinium? murochoratum has only 5 postcingular plates, with the ridge tile plate representing the ridge tile plate.
The leftward displacement of the hypocyst relative to the epicyst is only vaguely visible in Cribroperidinium? murohoratum. The parasutures of the 3"/4" and the 3'"/4'" are opposite each other, while the parasuture 2"'/3"' is clearly shifted to the left relative to the parasuture 2"/3".
The antapical view (Fig. 2d) shows that not only plate 1"" is symmetrical, but the entire antapex is largely symmetrical.
The dorsal contact of 4' and 2', as well as a porichnion, could not be detected (HELENES, 1984).
Apically, the parasutural septa often form a small horn. The autophragm between the septa is smooth; trabecular structures are present only on plate 1"".
The penitabular septa appear to demarcate the growth streaks (GOCHT, 1979). Additional radial septa occur on the hypocyst, particularly prominent on plate 4'" (Fig. 6, Fig. 8).
Differentiation:
Cribroperidinium murochoratum differs from all other species of the genus Cribroperidinium by its high parasutural and penitabular septa. Cribroperidinium rassinervum (DEFLANDRE 1939) NOHR-HANSEN 1986 shows a greater displacement of the hypocyst to the left relative to the epicyst than Cribroperidinium murochoratum. The species of the genus Pterodinium EISENACK, 1958 differ from Cribroperidinium murochoratum by the septum of the penitabular septa.
Dimensions:
Holotype: Length with septa 99 μm, without septa 66 μm.
Width with septa 81 μm, without septa 60 μm. μm.
Range of variation: (40 measured specimens)
Length with septa 80-108 μm.
Width with septa 60-96 μm.
Septa height 5-12 μm.
Occurrence:
The species occurs at a frequency of 2-5% in samples from the White Jurassic delta (mutabilis zone) in southern Germany.
Cribroperidinium? murochoratum Dürr, 1987, p.72–74, fig.2; fig.4, nos.1–2; fig.5, nos.6–7; fig.6, nos.4,6–8. Holotype: Dürr, 1987, fig.4, nos.1–2. Questionable assignment: Dürr (1987, p.72). Age: middle Kimmeridgian.
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Original description: [Dürr, 1987] (translated from German):
Cribroperidinium murochoratum n. sp.
Fig. 2; Fig. 4, Figs. 1, 2, Fig. 5. Fig. 6, 7; Fig. 6, Figs. 4, 6-8
Holotype: Specimen GPIT 1663-1; Fig. 4, Figs. 1-2.
Paratypoids: Specimens GPIT 1663/2, 1663/12 Nos. 18, 23, 29.
Fig. 5, Figs. 6-7; Fig. 6, Figs. 4, 6-8.
Typical stratum: White Jurassic S (mutabilis zone), sample GE-12, from the uppermost part of the lowest marl band.
Typical locus: Quarry of the gravel works east of Genkingen, TK 25:7521 - Reutlingen; Coordinates: r^(35)15300/h^(53)64150.
Derivation: murochorate (after EVITT, 1985) Parasutures with septa, referring to the ornamentation of the surface.
Diagnosis: A species of the genus Cribroperidinium with high parasutural and additional penitabular and radial septa. Paratabulation: 6", 5"', 4', 6c, 6-7s, 1p, 1"", flagellar field.
Description:
The cyst is ovoid to pentagonal with high parasutural, penitabular, and radial septa. It shows the following paratabulation pattern: 6", 5"', 4', 6c, 6-7s, 1p, 1"", flagellar field. Archaeopyle 3".
Plate sp is sickle-shaped and, shifted to the right, extends almost to the paracingulum.
Plate ssa is probably homologous to the 1'" in other Cribroperidinium species; however, it has migrated into the sulcal field and no longer has a direct connection to the paracingulum. This indicates that Cribroperidinium? murochoratum has only 5 postcingular plates, with the ridge tile plate representing the ridge tile plate.
The leftward displacement of the hypocyst relative to the epicyst is only vaguely visible in Cribroperidinium? murohoratum. The parasutures of the 3"/4" and the 3'"/4'" are opposite each other, while the parasuture 2"'/3"' is clearly shifted to the left relative to the parasuture 2"/3".
The antapical view (Fig. 2d) shows that not only plate 1"" is symmetrical, but the entire antapex is largely symmetrical.
The dorsal contact of 4' and 2', as well as a porichnion, could not be detected (HELENES, 1984).
Apically, the parasutural septa often form a small horn. The autophragm between the septa is smooth; trabecular structures are present only on plate 1"".
The penitabular septa appear to demarcate the growth streaks (GOCHT, 1979). Additional radial septa occur on the hypocyst, particularly prominent on plate 4'" (Fig. 6, Fig. 8).
Differentiation:
Cribroperidinium murochoratum differs from all other species of the genus Cribroperidinium by its high parasutural and penitabular septa. Cribroperidinium rassinervum (DEFLANDRE 1939) NOHR-HANSEN 1986 shows a greater displacement of the hypocyst to the left relative to the epicyst than Cribroperidinium murochoratum. The species of the genus Pterodinium EISENACK, 1958 differ from Cribroperidinium murochoratum by the septum of the penitabular septa.
Dimensions:
Holotype: Length with septa 99 μm, without septa 66 μm.
Width with septa 81 μm, without septa 60 μm. μm.
Range of variation: (40 measured specimens)
Length with septa 80-108 μm.
Width with septa 60-96 μm.
Septa height 5-12 μm.
Occurrence:
The species occurs at a frequency of 2-5% in samples from the White Jurassic delta (mutabilis zone) in southern Germany.