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Hystrichosphaerina

From Williams et al., 2017:

[Hystrichosphaerina, Alberti, 1961, p. 38; Emendation: Stancliffe and Sarjeant, 1990, p. 204

tax. jr. syn. of Systematophora Klement, 1960, according to Downie and Sarjeant, 1965, Sarjeant, 1966, and Brenner, 1988. Stover and Evitt, 1978, and Stancliffe and Sarjeant, 1990, retained Hystrichosphaerina as a separate genus.
tax. sr. syn. of Polystephanephorus Sarjeant, 1961, according to Duxbury, 1980. Lentin and Williams, 1981. and Davey, 1982, retained Polystephanephorus as a separate genus.

Type species: Hystrichosphaerina schindewolfii, Alberti, 1961 (pl.10, figs.2–3)]

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Original description: [Alberti, 1961]: (Translation: Stover and Evitt, 1978, p. 57):

Description:
Shell spherical to roughly oval. With numerous radially arranged, vase or beaker-like processes, whose wall is perforated in mesh or net-like fashion. The meshes are often elongate and commonly extend from the base to the upper edge of the processes. This edge is almost continuous, often slightly denticulate. The wall of the "beakers" is often so widely broken up that the latter consist of single "rods" which stand in the direction of their long axis, arranged in circles (most of them more or less deviating there from) on the shell, and which are more or less expanded and interconnected at their bases as well as at their upper ends. Sometimes a few long, thin processes, which are generally branched distally, are situated in an equatorial zone (?). No connecting filaments between the ends of the individual processes.

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Modified description:

Stover and Evitt, 1978, p. 57-58:

Synopsis:
Cysts skolochorate, gonyaulacacean; body subspherical with about 18 cylindrical to trumpet-shaped penitabular process groups, each group linked distally by ring trabeculae; paracingular processes slender, branched, and not interconnected distally; archeopyle apical, Type tA.

Description:
Shape: Body subspherical.
Wall relationships: Autophragm only.
Wall features: No parasutural features. Penitabular process groups cylindrical to trumpet-shaped, each group connected distally by ring trabeculae; paracingular processes isolated, slender, branched, and not interconnected distally. Autophragm between processes smooth or faintly ornamented.
Paratabulation: Indicated clearly by penitabular process groups and less distinctly by isolated paracingular processes; gonyaulacacean, process formula: ?4`, 6", 4-6c, 5-6```, 1p, 1````. When five postcingular process groups are present, these are interpreted as occurring on paraplates 2``` to 6```.
Archeopyle: Apical, Type (tA); principal archeopyle suture appears to be zigzag; operculum free. Exact shape of operculum and number of process groups on it are unknown.
Paracingulum: Indicated indistinctly by four to six isolated, distally branched processes.
Parasulcus: Expression unknown.
Size: Intermediate to large.

Affinities:
Hystrichosphaerina differs from Emmetrocysta in having isolated, distally branched paracingular processes; Emmetrocysta does not have paracingular processes.

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Emended description:


Stancliffe and Sarjeant, 1990:

Diagnosis:
Central body spherical to subspherical, with a smooth to granular phragma. About 18 large intratabular clusters, with approximately 5 to 10 processes per cluster, are developed; the clusters flare distally in a trumpet-like fashion. Processes thin, solid, occasionally thickening distally, with smooth to granular walls. Complex branching occurs along the length of the processes, two orders of branching being commonly developed. The process clusters are capped by ring trabeculae which may be denticulate distally. Inter-cluster trabeculae may be present or absent. Cingulum marked either by a few isolated long, thin, distally bifid processes or by an area devoid of processes.
Paratabulation ?4`, 6", 4-6c, 5-6```, 1p, 1````.
Archeopyle apical, type (tA), with a zig-zag margin and free operculum.


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Notes:

G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.

Hystrichosphaerina Alberti, 1961, emend. Stancliffe and Sarjeant, 1990. According to Stancliffe and Sarjeant (1990, p.204), Hystrichosphaerina has a central body which is spherical to subspherical, with a smooth to granular phragma. About 18 large intratabular clusters, with about 5-10 processes per cluster, are developed; the clusters flare distally in a trumpet-like fashion. Processes thin, solid, occasionally thickening distally, with smooth to granular walls. Complex branching occurs along the length of the processes, two orders of branching being commonly developed. The process clusters are capped by ring trabeculae which may be denticulate distally. Inter-cluster trabeculae may be present or absent. Cingulum marked either by a few isolated long, thin, distally bifid processes or by an area devoid of processes. Paratabulation ?4`, 6", 4-6c, 5-6"'. 1p, 1"''. Archeopyle apical, type (tAO, with a zig-zag margin and free operculum.
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