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Cribroperidinium ehrenbergii
Cribroperidinium ehrenbergii (Gitmez, 1970) Helenes, 1984
Originally Gonyaulacysta, subsequently Millioudodinium, thirdly (and now) Cribroperidinium.
Helenes, 1984, and Jan du Chene et al., 1986, regarded this as a problematical species of Cribroperidinium. Lentin and Williams, 1989, recommended that the name be restricted to the holotype.
Holotype: Gitmez, 1970, pl.2, fig.8-9, text-fig.8 (lost according to Jan du Chene et al., 1986)
Locus typicus: S side of Cap de La Creche, Boulonnais, France
Stratum typicum: Early Kimmeridgian
Original diagnosis: Gitmez, 1970, p.252-253: Gonyaulacysta ehrenbergii
Gonyaulacysta having an ovoidal theca of moderate wall thickness, with an apical horn. Tabulation: 4", 1a, 6"", 6c, 7""", 1p, 1pv, 1""""; sutures in form of moderately high, membraneous crests giving rise occasionally to short, blunt spines.
Cingulum narrow, helicoid, laevorotatory; sulcus of moderate breadth. Shell surface densely granular. Large precingular archaeopyle formed by loss of plate 3".
Dimensions: Holotype: overall length 70 Ám, breadth 50 Ám; horn length 8 Ám; breadth of the cingulum 5-8 Ám. Range (5 specimens measured): overall length 70-80 Ám, breadth 50-65 Ám; horn length 6-9 Ám.
Original description: Gitmez, 1970, p.253: Gonyaulacysta ehrenbergii
The shell is broadly ovoidal, giving rise to a strong apical horn; this is formed by three of the four apical plates (plates 1", 2" and 4"). Apical plates 1" and 4" are larger than the other two plates; 1" is elongate. The single anterior intercalary plate 1a is large and located between the apical plates 3", 4" and precingular plates 4", 5", 6". The precingular plates are generally large, plates 5" and 6"" being reduced to accommodate the intercalary plate 1a.
Seven postcingular plates are present: Plates 1""" and 2""" are reduced because of the large intercalary plate 1p; plates 6""" and 7""" are also reduced, since the large antapical plate 1"""" occupies a large area. The presence of posterior intercalary plate 1pv and the sulcal plates render the sulcus short and narrow.
Affinities:
Gitmez, 1970, p.253-254: Gonyaulacysta ehrenbergii
Five specimens of this infrequent species were observed; all of them are well preserved. All records were from French assemblages--from Normandy, and the Boulonnais. The generic allocation of Gonyaulacysta ehrenbergii is questionable, in view of its possession of a seventh postcingular plate. The similarity in general morphology to a number of species of Gonyaulacysta resulted in its allocation to that genus. Since it possesses seven postcingular plates, there is a similarity between this species and the species of Cryptarchaeodinium; but the Cryptarchaeodinium species so far observed have a slightly different tabulation, with plate 2p and without the sulcal plates. One species of that genus, described for the first time in this paper, bears a blunt apical horn; but the apical horn of G. ehrenbergii is longer than the horn observed in Cryptarchaeodinium. G. ehrenbergii is twice the size of any described species of Cryptarchaeodinium.
With seven post-cingular plates, this new species is similar to G. fetchamensis and G. palla; but it differs in details of tabulation, general aspect and size. The general structure and thick wall render this species similar to G. scotti, which was recorded from Lower Kimmeridgian of Australia by Cookson and Eisenack (1958); since Cookson and Eisenack were unable to determine the tabulation of G. scotti, of which they give a very incomplete description, and since the holotype was not available for study, the relationships between this latter species and G. ehrenbergii can not be commented on.
Poulsen, 1996, p. 72
Cribroperidinium ehrenbergii (Gitmez 1970) Helenes 1984.
Remarks. The holotype of the species was lost according to the British Museum (Natural History; see also Jan du Chene et al., 1986, p. 80). No other specimens were illustrated by Gitmez (1970). Helenes (1984, p. 124-125) included this species, together with Cribroperidinium caudum, Cribroperidinium globatum, and Cribroperidinium systremmatum, in the informal "Ehrenbergii Group", believing that they are probably conspecific forms. The characteristics of the "Ehrenbergii Group" were not described in detail by Helenes (1984, p. 124-125). The four species were regarded as closely related forms differentiated mainly on the basis of spinosity (Helenes, 1984). I concur with Helenes (1984) that these four species are taxonomic synonyms, but since the holotype of C. ehrenbergii is lost, I recommend that the name to be restricted to the holotype.
The illustration of C. ehrenbergii as shown in Gitmez (1970, text-fig. 8) looks typically cribroperidinioid, however, she obviously regarded some secondary sutures as primary sutures. The la paraplate is accordingly the upper part of the 5" paraplate. Paraplate 6"" is the other half of paraplate 5"". Paraplate 7"" is then paraplate 6"".
Originally Gonyaulacysta, subsequently Millioudodinium, thirdly (and now) Cribroperidinium.
Helenes, 1984, and Jan du Chene et al., 1986, regarded this as a problematical species of Cribroperidinium. Lentin and Williams, 1989, recommended that the name be restricted to the holotype.
Holotype: Gitmez, 1970, pl.2, fig.8-9, text-fig.8 (lost according to Jan du Chene et al., 1986)
Locus typicus: S side of Cap de La Creche, Boulonnais, France
Stratum typicum: Early Kimmeridgian
Original diagnosis: Gitmez, 1970, p.252-253: Gonyaulacysta ehrenbergii
Gonyaulacysta having an ovoidal theca of moderate wall thickness, with an apical horn. Tabulation: 4", 1a, 6"", 6c, 7""", 1p, 1pv, 1""""; sutures in form of moderately high, membraneous crests giving rise occasionally to short, blunt spines.
Cingulum narrow, helicoid, laevorotatory; sulcus of moderate breadth. Shell surface densely granular. Large precingular archaeopyle formed by loss of plate 3".
Dimensions: Holotype: overall length 70 Ám, breadth 50 Ám; horn length 8 Ám; breadth of the cingulum 5-8 Ám. Range (5 specimens measured): overall length 70-80 Ám, breadth 50-65 Ám; horn length 6-9 Ám.
Original description: Gitmez, 1970, p.253: Gonyaulacysta ehrenbergii
The shell is broadly ovoidal, giving rise to a strong apical horn; this is formed by three of the four apical plates (plates 1", 2" and 4"). Apical plates 1" and 4" are larger than the other two plates; 1" is elongate. The single anterior intercalary plate 1a is large and located between the apical plates 3", 4" and precingular plates 4", 5", 6". The precingular plates are generally large, plates 5" and 6"" being reduced to accommodate the intercalary plate 1a.
Seven postcingular plates are present: Plates 1""" and 2""" are reduced because of the large intercalary plate 1p; plates 6""" and 7""" are also reduced, since the large antapical plate 1"""" occupies a large area. The presence of posterior intercalary plate 1pv and the sulcal plates render the sulcus short and narrow.
Affinities:
Gitmez, 1970, p.253-254: Gonyaulacysta ehrenbergii
Five specimens of this infrequent species were observed; all of them are well preserved. All records were from French assemblages--from Normandy, and the Boulonnais. The generic allocation of Gonyaulacysta ehrenbergii is questionable, in view of its possession of a seventh postcingular plate. The similarity in general morphology to a number of species of Gonyaulacysta resulted in its allocation to that genus. Since it possesses seven postcingular plates, there is a similarity between this species and the species of Cryptarchaeodinium; but the Cryptarchaeodinium species so far observed have a slightly different tabulation, with plate 2p and without the sulcal plates. One species of that genus, described for the first time in this paper, bears a blunt apical horn; but the apical horn of G. ehrenbergii is longer than the horn observed in Cryptarchaeodinium. G. ehrenbergii is twice the size of any described species of Cryptarchaeodinium.
With seven post-cingular plates, this new species is similar to G. fetchamensis and G. palla; but it differs in details of tabulation, general aspect and size. The general structure and thick wall render this species similar to G. scotti, which was recorded from Lower Kimmeridgian of Australia by Cookson and Eisenack (1958); since Cookson and Eisenack were unable to determine the tabulation of G. scotti, of which they give a very incomplete description, and since the holotype was not available for study, the relationships between this latter species and G. ehrenbergii can not be commented on.
Poulsen, 1996, p. 72
Cribroperidinium ehrenbergii (Gitmez 1970) Helenes 1984.
Remarks. The holotype of the species was lost according to the British Museum (Natural History; see also Jan du Chene et al., 1986, p. 80). No other specimens were illustrated by Gitmez (1970). Helenes (1984, p. 124-125) included this species, together with Cribroperidinium caudum, Cribroperidinium globatum, and Cribroperidinium systremmatum, in the informal "Ehrenbergii Group", believing that they are probably conspecific forms. The characteristics of the "Ehrenbergii Group" were not described in detail by Helenes (1984, p. 124-125). The four species were regarded as closely related forms differentiated mainly on the basis of spinosity (Helenes, 1984). I concur with Helenes (1984) that these four species are taxonomic synonyms, but since the holotype of C. ehrenbergii is lost, I recommend that the name to be restricted to the holotype.
The illustration of C. ehrenbergii as shown in Gitmez (1970, text-fig. 8) looks typically cribroperidinioid, however, she obviously regarded some secondary sutures as primary sutures. The la paraplate is accordingly the upper part of the 5" paraplate. Paraplate 6"" is the other half of paraplate 5"". Paraplate 7"" is then paraplate 6"".