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Phthanoperidinium campoense
From Fensome et al., 2019:
Phthanoperidinium? campoense Caro, 1973, p.359–360, pl.4, fig.7. Holotype: Caro, 1973, pl.4, fig.7. Originally Phthanoperidinium, subsequently (and now) Phthanoperidinium?. Questionable assignment: Stover and Evitt (1978, p.119). Age: Early Eocene.
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Original description, Caro 1973, p. 359-360: Phthanoperidinium campoense, sp.nov. (Pl. 4, fig. 7)
Origin of the name: Campo (Prov. of Huesca, Spain), location of the section studied
Diagnosis: Theca with convex edges possessing a short apical horn and a single antapical horn. The suture lines are marked by an irregular membrane surmounted by short, irregularly distributed appendages. The tabulation would be 3' (or 4') 3a, 6'', 6c, 5''', 1p.i., 1''''. The archaeopyle would be intercalary, loss of the 3a plates.
Holotype: slide 642 (2), section from Campo
Holotype dimensions (only 1 individual present at Campo):
Height, 45 µm,
Width, 43 µm
Membrane, height, 3 µm
Appendages, length, 2 µm
Cingulum, average thickness: 5 µm
Archaeopyle, average width: 15 to 20 µm
Description: The apical horn is short, more or less hidden by the collar formed by the membrane on the sutures of the apical plates. The extensions of the laminae in short appendages are irregularly distributed and also irregular in height. The cingulum is helical, leaving on the ventral face a very wide and long sulcal surface, bordered by very small sulcal plates (2 or 3) on the hypotheses. A smaller plate also exists at the edge of the longitudinal groove, near the 1''' plate.
Note: Although the tabulation of the present space does not correspond exactly to the tabulation described by Drugg and Loeblich (1967) for the type species P. amaenum, i.e. 4’, 3a, 7’’, 5c, 5’’’, la-pl., 1d-pl., 1 S. pl., 1 p. pl/, 2’’’’, the tabulation we give for the present species does not deviate too much from it. It should be noted that we have observed only one individual, the only one present in the samples, and that the observation of the antapical plates is difficult. It is possible that the small plates observed in the epitheca (near the 1’’ plate) and in the hypotheca (sulcal plates) correspond to the “platelets” of Drugg and Loeblich 1a. pl., 1d-pl., 1 S. pl. The archaeopyle corresponds in the present space to plates 3a. Eaton (1969) mentions about P. tritonium that in one individual the 3 intercalary plates (3a) are absent. Hussain (1967) created a new genus Downiea, type species: Downiea diodontos whose generic characters, archaeopyle corresponding to the three intercalary plates 3 a, wide longitudinal groove, tabulation, are observable characters in the present species. The genus created by Hussain was described in an unpublished university thesis and is not valid. The present space cannot be included in the genus Spinidinium (Spinidinium styloniferum) Cookson and Eisenack 1962. The type species, although very close in appearance to P. campoense, does not have apparent tabulation.
Phthanoperidinium? campoense Caro, 1973, p.359–360, pl.4, fig.7. Holotype: Caro, 1973, pl.4, fig.7. Originally Phthanoperidinium, subsequently (and now) Phthanoperidinium?. Questionable assignment: Stover and Evitt (1978, p.119). Age: Early Eocene.
---------------------------------------------------------------------------------------------------
Original description, Caro 1973, p. 359-360: Phthanoperidinium campoense, sp.nov. (Pl. 4, fig. 7)
Origin of the name: Campo (Prov. of Huesca, Spain), location of the section studied
Diagnosis: Theca with convex edges possessing a short apical horn and a single antapical horn. The suture lines are marked by an irregular membrane surmounted by short, irregularly distributed appendages. The tabulation would be 3' (or 4') 3a, 6'', 6c, 5''', 1p.i., 1''''. The archaeopyle would be intercalary, loss of the 3a plates.
Holotype: slide 642 (2), section from Campo
Holotype dimensions (only 1 individual present at Campo):
Height, 45 µm,
Width, 43 µm
Membrane, height, 3 µm
Appendages, length, 2 µm
Cingulum, average thickness: 5 µm
Archaeopyle, average width: 15 to 20 µm
Description: The apical horn is short, more or less hidden by the collar formed by the membrane on the sutures of the apical plates. The extensions of the laminae in short appendages are irregularly distributed and also irregular in height. The cingulum is helical, leaving on the ventral face a very wide and long sulcal surface, bordered by very small sulcal plates (2 or 3) on the hypotheses. A smaller plate also exists at the edge of the longitudinal groove, near the 1''' plate.
Note: Although the tabulation of the present space does not correspond exactly to the tabulation described by Drugg and Loeblich (1967) for the type species P. amaenum, i.e. 4’, 3a, 7’’, 5c, 5’’’, la-pl., 1d-pl., 1 S. pl., 1 p. pl/, 2’’’’, the tabulation we give for the present species does not deviate too much from it. It should be noted that we have observed only one individual, the only one present in the samples, and that the observation of the antapical plates is difficult. It is possible that the small plates observed in the epitheca (near the 1’’ plate) and in the hypotheca (sulcal plates) correspond to the “platelets” of Drugg and Loeblich 1a. pl., 1d-pl., 1 S. pl. The archaeopyle corresponds in the present space to plates 3a. Eaton (1969) mentions about P. tritonium that in one individual the 3 intercalary plates (3a) are absent. Hussain (1967) created a new genus Downiea, type species: Downiea diodontos whose generic characters, archaeopyle corresponding to the three intercalary plates 3 a, wide longitudinal groove, tabulation, are observable characters in the present species. The genus created by Hussain was described in an unpublished university thesis and is not valid. The present space cannot be included in the genus Spinidinium (Spinidinium styloniferum) Cookson and Eisenack 1962. The type species, although very close in appearance to P. campoense, does not have apparent tabulation.