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Parvocavatus scabratus

Parvocavatus scabratus Kumar, 1986

Now Dingodinium. Originally Parvocavatus, subsequently (and now) Dingodinium.
Taxonomic senior synonym: Dingodinium minutum Dodekova, according to Poulsen (1996, p.82).

Holotype: Kumar, 1986, pl.6, fig.6
Locus typicus: Dorset, England
Stratum typicum: Kimmeridgian-Tithonian

Original diagnosis: Kumar, 1986, p.399
Camocavate, subsphaerical cyst with a short apical horn. Paratabulation is gonyaulacacean, and is marked by faintly developed ridges on the endophragm. Archaeopyle apical and marked by a schism only, operculum attached. Paracingulum is circular and parasulcus is indistinct. Periphragm is thin and psilate, endophragm thick and scabrate to finely granulate.

Original description: Kumar, 1986, p.399
These are camocavate, subsphaerical cysts with a short apical horn, which is distally open and blunt. Paratabulation is gonyaulacacean and is marked by low ridges on the endophragm. The exact number and arrangement of paraplates is not clear. A paracingulum divides the endocyst in almost equal halves. Parasulcus is not clearly visible. The archaeopyle is apical, and it is formed by a schism near the apical region. The operculum is attached. The wall is double layered. The periphragm is thin, psilate and forms a short apical horn. The endophragm is thicker and forms a sphaerical to subsphaerical endocoel. The ornamentation on the endophragm is generally scabrate, but it may also be finely granulate. The periphragm and endophragm are in contact only on the dorsal side and the rest of the region forms a cavity.

Dimension:
Based on seven specimens. Cyst length 55.0-61.5 µm, Cyst width 49.0-55.0 µm.

Affinities:
Kumar, 1986, p.399: P. scabratus differs from P. tuberosus Gitmez (1970) in having a scabrate or finely granulate endophragm rather than having a densely tuberculate endophragm. P. scabratus is camocavate and P. tuberosus is cornucavate, and finally, P. scabratus does not show a distinct arrangement of paraplates and a parasulcus.
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