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Cribroperidinium globatum

Cribroperidinium globatum (Gitmez and Sarjeant, 1972, p.195,197, pl.3, figs.1-2; text-figs.5A-B) Helenes, 1984, p.124.

Originally Gonyaulacysta, subsequently Millioudodinium, thirdly Rhynchodiniopsis, fourthly Cribroperidinium?, fifthly (and now) Cribroperidinium. Questionable assignment: Helenes (1984, p.124) as a problematic species - however, Poulsen (1996, p.72) included the species in Cribroperidinium without question.
Taxonomic junior synonyms: Gonyaulacysta cauda and Gonyaulacysta systremmata, both according to Poulsen (1996, p.72).

Holotype: Gitmez and Sarjeant, 1972, pl.3, fig.1; text-fig.5A; Jan du Chêne et al., 1986a, pl.29, fig.3.
Paratype: Gitmez and Sarjeant, 1972
Age: mid-late Kimmeridgian.

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

Cribroperidinium globatum (Gitmez and Sarjeant, 1972) Helenes, 1984 is subspherical to broadly oval with a strong apical horn. The sutural crests are low. The surface is densely granular.The species differs from C.nuciforme in having a relatively thin wall and in the dissimilar ventral antapical tabulation. Size: length 85-92 µm, width 62-75 µm, horn length 11-12 µm.
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Original diagnosis: Gitmez and Sarjeant, 1972, p.195, 197: Gonyaulacysta globata
A proximate cyst, subsphaerical to broadly oval with a strong apical horn. The sutural crests are low, generally well defined, and reflect the tabulation 4', 1a, 6'' 6c, 6''', ?1p, 1''''. Cingulum moderately narrow, helicoid, laevorotatory, dividing the theca unequally, the epitract being longer than the hypotract. The sulcus is broad. The surface of the shell is densely granular. A precingular archaeopyle, formed by the loss of plate 3'', is developed in some instances.
Dimensions: Holotype: overall length 90 Ám, breadth 68 Ám, apical horn length 11 Ám. Range: overall length 85-92 Ám, breadth 62-75 Ám, horn length11-12 Ám.

Original description: Gitmez and Sarjeant, 1972, p.197: Gonyaulacysta globata
The cyst is globular, relatively thin-walled. Four apical plates combine to form the slender horn. Plate 1' is narrow and elongate, the other apical plates are approximately polygonal but with an apical prolongation. A single anterior intercalary plate is present and qiute large, apical plate 4' and precingular plates 5'' and 6'' being correspondingly reduced. The four other precingular plates are large. The cingular plates are poorly defined, but appear to number six. The hypotract is dome-shaped, composed of large reflected plates, plate 4''' is the largest of all. Plate 1''' is greatly reduced; plates 5'''and 6''' are relatively small. The boundary between the plates 1p and 2''' was not confirmed. The single antapical plate, 1'''' is also large. The sulcus is narrow in its anterior portion, broadening to cantact with the cingulum and thenceforward remaining of constant breadth in its posterior portion. It is relatively short and extends to the antapex. In one specimen only, a precingular archaeopyle was seen.

Poulsen, 1996, p. 72-73
Cribroperidinium globatum (Gitmez & Sarjeant 1972) Helenes 1984
Pl. 7, Figs. 1-5, Pl. 8, Figs. 1-3
Gonyaulacysta globata Gitmez and Sarjeant, 1972, p. 195-197, pl. 3, figs. 1-2, text-figs. 5 A-B.
Gonyaulacysta cauda Gitmez and Sarjeant, 1972, p. 193-194, pl. 2, figs. 1, 2, 4, 5. Onginally Gonyaulacysta sp. B of Gitmez 1970, p. 264-265, pl. 6, fig. 3, text-fig. 14.
Gonyaulacysta systremmata Gitmez and Sarjeant, 1972, p. 204-205, pl. 5, figs. 7-8. Onginally Gonyaulacysta sp. C of Gitmez 1970, p. 265-267, pl. 4, figs. 10-11, text-fig. 15.
Remarks. This species is widely distributed in the Kimmeridgian to Early Volgian of northern Europe. It has a spinose surface, with a varying degree of spinosity from specimen to specimen. It resembles Cribroperidinium granulatum and Cribroperidinium granuligerum, but C. globatum has a distinct short, truncate to trumpet-shaped horn. The horn of C. granulatum, although also short and truncate, is for most of its length composed of spines only, and it is more conical.
The type material has been re-studied and is re-illustrated herein. Gonyaulacysta globata: holotype Pl. 7. Figs. 1-3; paratype Pl. 7, Fig 4. Gonyaulacysta cauda: Holotype is lost according to British Museum (Natural History); paratype Pl. 7, Fig. 5. Gonyaulacysta systremmata: holotype Pl. 8. Fig. 1.
I consider C. globatum, C. cauda, and C. systremmatum to be taxonomic synonyms. The holotype of C. globatum is in a better state of preservation than the holotypes of C. cauda and C. systremmatum, however, so I propose retention of C. globatum and suppression of the names C. cauda and C. systremmatum. The paratabulation of C. globatum and its taxonomic synonyms, as illustrated by Gitmez (1970, text-figs. 14, 15) is cribroperidinioid. However, the paraplate designations need reinterpretation.
The paratabulation of the holotype (illustrated by Gitmez and Sarjeant, 1972, text-fig. 5A), is here redefined. The ridge originally interpreted as the parasuture 2'/3', represent a growth line in the middle of paraplate 2'. Consequently the two paraplates 2' and 3' in the Gitmez and Sarjeant illustration represent paraplate 2' only. The paraplates 4' and la in the Gitmez and Sarjeant illustration are 3' and 4' respectively. (See also Pl. 7, Figs. 1-3).
The paratype of C. caudum is obscured by amorphous material. The very long "parasutural spines" on the hypocyst illustrated in Gitmez (1970, text-fig. 14) consist mainly of amorphous material and are not part of the cyst (Pl. 7, Fig. 5). The paratabulation of the paratype (illustrated by Gitmez and Sarjeant, 1972, text-fig. 5B), is reinterpreted here. The paraplates 3' and 4' on their textfig. 5B represent only paraplate 3', and as for the holotype of C. globatum, paraplate la is 4'. The parasuture 4'/1a in Gitmez (1970, text-fig. 14) is a fold or secondary parasuture. In the hypocystal paratabulation Gitmez and Sarjeant regarded secondary parasutures as primary and labeled 1"' as s, 2"' as 1"', 3"' as 2"', 4"' as 3"', 5"' as 4"' plus 5"', and 6"' as 6"'. This specimen is now in poor condition and reinterpretation is only possible utilizing Gitmez and Sarjeant's illustrations.
The holotype of C. systremmatum is in very poor condition (Pl. 8, Fig. 1).
Dimensions. The length of the cyst, without the horn, is approximately 70 Ám. The length of the horn ranges between 7-22 Ám.
Holotype. BGS catalogue no.: PK 122; from Warlingham borehole at 2510 ft., Surrey, England, Volgian, (Wheatleyensis Zone).
Paratypes. BM(NH) V.53966( 1 ) (glycerol jelly has contracted, obscuring this specimen), V.56343(1), V.56345, and V.53965(2) (glycerol jelly has contracted, obscuring this specimen). (For sample details, see Gitmez, 1970; Gitmez and Sarjeant, 1972).
Recorded occurrences.
Denmark: Scriniodinium crystallinum Zone, Subzone b - Gochteodinia villosa Zone, Rotosphaeropsis thula Subzone.
Poland: Planula - Scythicus Zones.
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