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Hystrichokolpoma grimmertingenense
Hystrichokolpoma grimmertingenense de Coninck, 2001, p.14-15, pl.6, figs.10-12. Holotype: de Coninck, 2001, p.14-15, pl.6, figs.10-12. Age: early Rupelian.
Original description of H. grimmertingenensis, De Coninck, 2001
Derivation of name: Grimmertingen, the type locality of the Grimmertingen Sands Member.
Diagnosis: The cyst body is subspherical. Its wall is composed of an endo- and periphragm. Between the processes formed by the periphragm the surface is smooth, but underneath the large processes the endophragm appears finely granular. The archeopyle is apical. In cingular position occur some 30 very short and relatively narrow processes. These are tubular with a slightly widened top. In sulcal position one encounters about 8 small, conical and distally pointed processes. Above the series of cingular processes occur 6 large, hollow, conical and smooth precingular processes with slightly convex sides. Their narrow top seems ragged off. Below the cingular processes five hollow, conical and smooth postcingular processes, again with slightly convex sides, are found. One of them, representing plate 2 ’” , is distinctly smaller than the four other ones which are a little larger than the precingular processes. The antapical process is slightly striate lengthwise. It is as long as the postcingular processes but not as wide, with rather straight sides, narrowing suddenly below its more or less elongate and narrow end. Holotype: Grimmertingen -3.3 m. Grimmertingen Sands Member. Slide 3; coord. England Finder Z53(2). (PI. 6, figs. 10-12).
Paratype: Kallo borehole -110 m. Wintham Silt Member. Slide 3; coord. England Finder beyond Z44.
(no figures). Repository: Collection of the Laboratory of Paleontology of the Ghent University.
Dimensions of the holotype: Cyst body: 50 µm
precingular processes: 20 to 25 µm wide in their lower part; 35 to 40 µm long,
cingular processes: about 2 µm wide at the base; 8 µm long,
sulcal processes: 2 to 5 µm wide at the base; 10 to 18 µm long.
postcingular processes: The process on plate 2”” is about 14 µm wide at the base and 22 µm long. The
other four processes are 18 to 22 µm wide in their lower part and 40 to 45 µm long,
antapical process: about 17 µm wide and 45 µm long.
Dimensions of the paratype:
cyst body: 45 µm.
antapical process: 30 µm long and 17 µm wide,
other processes: same dimensions as in the holotype.
Comparison: H. grimmertingenensis nov. sp. clearly differs from the other species of the genus by its
large size in combination with slightly convex, conical pre- and postcingular processes. These processes are smooth, without the lateral or distal tubules which are observed on the large processes of H. cinctum Klummp, 1953 and of several other species of the genus. The numerous, very small cingular processes and the fine granulation of the endophragm underneath the large processes are also characteristic of the new species.
Original description of H. grimmertingenensis, De Coninck, 2001
Derivation of name: Grimmertingen, the type locality of the Grimmertingen Sands Member.
Diagnosis: The cyst body is subspherical. Its wall is composed of an endo- and periphragm. Between the processes formed by the periphragm the surface is smooth, but underneath the large processes the endophragm appears finely granular. The archeopyle is apical. In cingular position occur some 30 very short and relatively narrow processes. These are tubular with a slightly widened top. In sulcal position one encounters about 8 small, conical and distally pointed processes. Above the series of cingular processes occur 6 large, hollow, conical and smooth precingular processes with slightly convex sides. Their narrow top seems ragged off. Below the cingular processes five hollow, conical and smooth postcingular processes, again with slightly convex sides, are found. One of them, representing plate 2 ’” , is distinctly smaller than the four other ones which are a little larger than the precingular processes. The antapical process is slightly striate lengthwise. It is as long as the postcingular processes but not as wide, with rather straight sides, narrowing suddenly below its more or less elongate and narrow end. Holotype: Grimmertingen -3.3 m. Grimmertingen Sands Member. Slide 3; coord. England Finder Z53(2). (PI. 6, figs. 10-12).
Paratype: Kallo borehole -110 m. Wintham Silt Member. Slide 3; coord. England Finder beyond Z44.
(no figures). Repository: Collection of the Laboratory of Paleontology of the Ghent University.
Dimensions of the holotype: Cyst body: 50 µm
precingular processes: 20 to 25 µm wide in their lower part; 35 to 40 µm long,
cingular processes: about 2 µm wide at the base; 8 µm long,
sulcal processes: 2 to 5 µm wide at the base; 10 to 18 µm long.
postcingular processes: The process on plate 2”” is about 14 µm wide at the base and 22 µm long. The
other four processes are 18 to 22 µm wide in their lower part and 40 to 45 µm long,
antapical process: about 17 µm wide and 45 µm long.
Dimensions of the paratype:
cyst body: 45 µm.
antapical process: 30 µm long and 17 µm wide,
other processes: same dimensions as in the holotype.
Comparison: H. grimmertingenensis nov. sp. clearly differs from the other species of the genus by its
large size in combination with slightly convex, conical pre- and postcingular processes. These processes are smooth, without the lateral or distal tubules which are observed on the large processes of H. cinctum Klummp, 1953 and of several other species of the genus. The numerous, very small cingular processes and the fine granulation of the endophragm underneath the large processes are also characteristic of the new species.