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Fibrocysta deflandrei
Fibrocysta deflandrei (Lejeune-Carpentier, 1941) emend. Lejeune-Carpentier and Sarjeant, 1981
Originally Hystrichosphaeridium spinosum var. deflandrei, subsequently Baltisphaeridium spinosum var. deflandrei, thirdly Exochosphaeridium spinosum var. deflandrei, fourthly Exochosphaeridium spinosum ssp. deflandrei, fifthly Exochosphaeridium? spinosum ssp. deflandrei, sixthly (and now) Fibrocysta? deflandrei. See also Cordosphaeridium spinosum var. deflandrei (combination not validly published).
At the time of the transfer, Lejeune-Carpentier and Sarjeant, 1981, questionably included this species in Fibrocysta.
Holotype Lejeune-Carpentier, 1941, fig. 6; Lejeune-Carpentier and Sarjeant 1981, pl. 4: 5-6, text-fig. 8.
Locus typicus: Flint from Craie de Spiennes (= Formatie van Gulpen of Felder, 1975), quarry of Mortiau, Cuesmes, (Hainaut), Belgium.
Stratum typicum: Upper Cretaceous, (Senonian)
Age: Late Cretaceous
Emended Diagnosis: Lejeune-Carpentier and Sarjeant 1981, p. 14, 15: Fibrocysta? deflandrei
Cyst broadly ellipsoidal, with a short, strong apical horn and a much less prominent, rather flattened antapical mamelon. Surface of phragma irregularly areolate, the elongation of the areolations around some processes suggesting a root-like structure. Processes non-tabular (or apparently so) and thornlike, broad and flattened at the base but tapering to an acute point their length shows some variation, but is always between one-third and one-half the shortest cyst diameter. Archaeopyle single-plate precingular (type P).
Dimensions Holotype: overall length of cyst 48 Ám, length of apical horn 5 Ám, height of antapical mamelon c. 2 Ám, breadth of cyst 39 Ám, length of processes up to 19Ám. Range of Dimensions: Overall length of cyst 36-49Ám, length of processes 14-21Ám.
Description: Lejeune-Carpentier and Sarjeant 1981, p. 14, 15: Fibrocysta? deflandrei
Our restudy showed that, instead of exhibiting the convergent web of rootlike extensions from process bases that the original figures (Lejeune~arpentier, 1941) suggest, the surface of the phragma has an irregular overall areolation with meshes of very variable size and shape. In some instances, these are indeed elongate and seem to converge on particular processes, so that their boundaries simulate roots; but in other instances, the meshes surrounding a process show no such relation to it, their shape instead appearing random.
The flattened bases of the spines are noteworthy, suggesting possible alignment along a reflected suture; but no pattern of process distribution could be elucidated and they must for the moment be regarded as non-tabular. The spines arising on and about the apical horn give a bifid appearance to that structure in some specimens: but this varies according to position.
Rernarks: Lejeune-Carpentier and Sarjeant 1981, p. 14, 15
White's illustrations of Xanthidium (now Exochosphaeridium) spinosum (1842) depict a more rotund form, with processes of dissimilar morphology and without apical or antapical protuberances. Our restudy makes it evident that the Belgian forms are certainly not conspecific, and indeed not even congeneric, with White's specimens. Since a survey of the literature has brought to light no species that is exactly comparable, the former variety deflandrei is here elevated to specific status.
In its overall shape, polar protrusions and possession of hollow, non tabular processes, this species accords with the diagnosis of Fibrocysta and in particular resembles F. Iappacea (Drugg, 1970) Stover and Evitt, 1978. However, it lacks the fibrous processes, with expanded or branching tips, characteristic of that genus, instead having pointed processes that are not evidently fibrous. Moreover, though the overall shape is strikingly similar to that of F. Iappacea, the processes are much longer and slimmer and the single-plate precingular archaeopyle appears less broad (though this may be a result of orientation). The species deflandrei is thus placed only tentatively into Fibrocysta and may shortly merit transfer to another genus yet undescribed.
Originally Hystrichosphaeridium spinosum var. deflandrei, subsequently Baltisphaeridium spinosum var. deflandrei, thirdly Exochosphaeridium spinosum var. deflandrei, fourthly Exochosphaeridium spinosum ssp. deflandrei, fifthly Exochosphaeridium? spinosum ssp. deflandrei, sixthly (and now) Fibrocysta? deflandrei. See also Cordosphaeridium spinosum var. deflandrei (combination not validly published).
At the time of the transfer, Lejeune-Carpentier and Sarjeant, 1981, questionably included this species in Fibrocysta.
Holotype Lejeune-Carpentier, 1941, fig. 6; Lejeune-Carpentier and Sarjeant 1981, pl. 4: 5-6, text-fig. 8.
Locus typicus: Flint from Craie de Spiennes (= Formatie van Gulpen of Felder, 1975), quarry of Mortiau, Cuesmes, (Hainaut), Belgium.
Stratum typicum: Upper Cretaceous, (Senonian)
Age: Late Cretaceous
Emended Diagnosis: Lejeune-Carpentier and Sarjeant 1981, p. 14, 15: Fibrocysta? deflandrei
Cyst broadly ellipsoidal, with a short, strong apical horn and a much less prominent, rather flattened antapical mamelon. Surface of phragma irregularly areolate, the elongation of the areolations around some processes suggesting a root-like structure. Processes non-tabular (or apparently so) and thornlike, broad and flattened at the base but tapering to an acute point their length shows some variation, but is always between one-third and one-half the shortest cyst diameter. Archaeopyle single-plate precingular (type P).
Dimensions Holotype: overall length of cyst 48 Ám, length of apical horn 5 Ám, height of antapical mamelon c. 2 Ám, breadth of cyst 39 Ám, length of processes up to 19Ám. Range of Dimensions: Overall length of cyst 36-49Ám, length of processes 14-21Ám.
Description: Lejeune-Carpentier and Sarjeant 1981, p. 14, 15: Fibrocysta? deflandrei
Our restudy showed that, instead of exhibiting the convergent web of rootlike extensions from process bases that the original figures (Lejeune~arpentier, 1941) suggest, the surface of the phragma has an irregular overall areolation with meshes of very variable size and shape. In some instances, these are indeed elongate and seem to converge on particular processes, so that their boundaries simulate roots; but in other instances, the meshes surrounding a process show no such relation to it, their shape instead appearing random.
The flattened bases of the spines are noteworthy, suggesting possible alignment along a reflected suture; but no pattern of process distribution could be elucidated and they must for the moment be regarded as non-tabular. The spines arising on and about the apical horn give a bifid appearance to that structure in some specimens: but this varies according to position.
Rernarks: Lejeune-Carpentier and Sarjeant 1981, p. 14, 15
White's illustrations of Xanthidium (now Exochosphaeridium) spinosum (1842) depict a more rotund form, with processes of dissimilar morphology and without apical or antapical protuberances. Our restudy makes it evident that the Belgian forms are certainly not conspecific, and indeed not even congeneric, with White's specimens. Since a survey of the literature has brought to light no species that is exactly comparable, the former variety deflandrei is here elevated to specific status.
In its overall shape, polar protrusions and possession of hollow, non tabular processes, this species accords with the diagnosis of Fibrocysta and in particular resembles F. Iappacea (Drugg, 1970) Stover and Evitt, 1978. However, it lacks the fibrous processes, with expanded or branching tips, characteristic of that genus, instead having pointed processes that are not evidently fibrous. Moreover, though the overall shape is strikingly similar to that of F. Iappacea, the processes are much longer and slimmer and the single-plate precingular archaeopyle appears less broad (though this may be a result of orientation). The species deflandrei is thus placed only tentatively into Fibrocysta and may shortly merit transfer to another genus yet undescribed.