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Glaphyrocysta pastielsii
Glaphyrocysta pastielsii (Deflandre and Cookson, 1955, p.285 ex de Coninck, 1965, p.44) Stover and Evitt, 1978, p.50. Emendation: Sarjeant, 1986, p.27-29, as Glaphyrocysta pastielsii.
Originally Cyclonephelium, subsequently (and now) Glaphyrocysta.
The name Cyclonephelium pastielsii was not validly published in Deflandre and Cookson (1955, p.285) since these authors did not provide a description or a direct reference to one (as required after 1952 by ICBN Article 32.3).
Holotype: Pastiels, 1948, pl.5, fig.15, as Membranilarnax cf. liradiscoidea; Fauconnier and Masure, 2004, pl.33, fig.9.
Age: Early Eocene.
Translation Pastiels, 1948, p. 47: LPP
Description: Pastiels, 1948, p. 47: Membranilarnax cf. liradiscoides O. Wetzel
Central capsule lenticular, ornamented in the equatorial region with radiating appendices, simple or bifurcate, joined distally by a network of tubular ramifications forming largely areolate meshes. The reproduction of the plate description of M. cf. liradiscoides, given by O. Wetzel, 1933, pl.6, fig. 3-4, is too incomplete to attribute this specimen to that species.
Diameter of the capsule 50 µm, total diameter approximately 80 µm.
Eaton, 1976, p. 259: Cyclonephelium pastielsii
Dimensions: Holotype: cyst body (without operculum) 53 x 57 Ám; length of processes up to 30 Ám.
Remarks: As in the case of Cyclonephelium exuberans, Deflandre & Cookson (1955: 285) also failed to designate a holotype for Cyclonephelium pastielsi, their new species name for forms described from the Lower Eocene of Belgium by Pastiels (1948) as Membranilarnax cf. Iiradiscoides 0. Wetzel 1933. However, since he only provided one illustration of M. cf. Iiradiscoides (Pastiels 1948: pl. 5, fig. 15, a probable camera lucida drawing) this must be the holotype, and it is here designated as such. Pastiels" original description of this form (1948: 47) indicates that it consists of a central body with processes restricted to the peripheral zone. The processes are simple or bifurcate, distally ramified and interconnected, and the illustrated specimen is devoid of them on reflected precingular plates 3"" and 6"".
In overall form the specimen illustrated by Pastiels is more closely comparable to Cyclonephelium retiintextum Cookson 1965 (De Coninck 1968: 41) than C. exuberans (Williams & Downie 1966: 225, 227). On this basis, C. pastielsi can only be considered to have been recorded from the Lower Eocene of Belgium (Pastiels 1948, as M. cf. Iiradiscoides; De Coninck 1965, 1968, Gruas-Cavagnetto 1968) and of northern France (Gruas-Cavagnetto 1968, 1970(b)). There are also several listed records without illustration or description which cannot be commented on: Lower Eocene of Belgium (De Coninck 1967), of northern France (Chateauneuf & Gruas-Cavagnetto 1968) and of the Hampshire Basin in southern England (Gruas-Cavagnetto 1970(a)); Middle Eocene of northern France (Gruas-Cavagnetto 1971).
Emended diagnosis: Sarjeant, 1986, p. 27-29: Glaphyrocysta pastielsii
Cyst lenticular, marginate and trabeculate. Ambitus broadly ovoidal, but with an asymmetrically situated antapical outbulge or broad, low horn (situated always to the left of the antapical pole in ventral view). Low surficial lines in the circumferential area may mark the positions of parasutures or may be lacking; normally the cingulum can be seen clearly only in the lateral regions. The mid-ventral and mid-dorsal regions lack ornament. Processes arise primarily or entirely from paraplate boundaries both in gonal and sutural positions. Their spacing is irregular, two to four parallel processes often arising close to a paraplate junction while the central sutural area lacks processes. They are short (in length, less than 1/3 the equatorial diameter of the cyst), very slender and apparently solid. The processes are linked distally by major trabeculae developed parallel to the paraplate boundaries. In addition meshworks of minor trabeculae may develop from the processes extending outward to join the major trabeculae and forming arch-like traceries beneath them. These meshworks are produced by the bifurcation or ramification the processes at about one-third height, the resultant branches being complexly interconnected. Archaeopyle apical, type (tA); sulcal notch and accessory sutures well marked. Operculum free.
Dimensions: Holotype: overall length 181 µm, length of central body (apex lacking) 48 µm, overall breadth 93 µm, breadth of central body 57 µm.
Discussion: A re-examination of the specimen figured by Pastiels (1948, pl. 5, fig. 15) shows his interpretative drawing to be, though correct enough in its major features, somewhat misleading in detail, the shape of the central body being less broad proportionately and the antapical prominence less evident than in reality. Moreover, the processes and the trabeculae are drawn too thick and their pattern of interconnexions is much simplified. The specimen illustrated as C. pastielsii by Williams and Downie (1966, pl. 25, fig. 2) does not appear to belong to this species. Although the photograph presented by Gocht (1969, pl. 8, fig. 15) provides a better basis for the interpretation of the morphology of this species, it is questionable whether, with these very different illustrations to serve as bases, subsequent identifications of this species have been correct.
Unfortunately, this is difficult to check since, in the majority of instances, no photographs are furnished in these later publications.
On the basis of these published records, Claphyrocysta pastielsii appears to have a stratigraphic range from Late Palaeocene (Thanetian) to Late Eocene (Bartonian); the few later records all appear doubtful. It has been reported from Belgium, the Netherlands, England, France, Germany, Italy, and from submarine cores from the Grand Banks and Scotian Shelf, offshore eastern Canada. The specimen from Spain illustratcd by Caro (1973) seems likely to prove attributable to a different species; and the systematic attribution of the specimens illustrated by De Coninck (1975) and Weiler (1980)) was properly regarded as questionable from the outset.
In their diagnosis of Glaphyrocysta, Stover and Evitt (1978, p. 69) noted that it has "No parasutural features." In the type species, G. retiinteeta (Cookson, 1965) Stover and Evitt, 1978, this may well be the case. However, the processes of G. pastielsii furnish a direct expression of the paratabulation, for they arise from parasutures (feebly marked or not at all) whose position is paralleled by the major trabeculae. In combination, these features permit the determination of a ceratioid paratabulation comparable (for instance) with that illustrated for Endoceratium ludbrookiae by Wall and Evitt (1975, text-fig. 9 D-E). The clear delimitation of the antapical paraplate (1"""") may be seen (pl. II, figs. 1, 3) and the enlarged illustrations here provided show how the boundaries of paraplates 4""" (Pl. II, fig. 5) and paraplate 2"" (Pl. II, fig. 4) can be distinguished without great difficulty. The displacement to the right of the bare midventral area (seen by transparency in pl. II, fig. 3) should also be noted. All in all, though the interpretation of the paratabulation in this species is difficult, it is by no means impossible. Since C. pastielsii thus has interconnected sutural processes rather than penitabular process complexes, its placement into the genus Glaphyrocysta, as presently defined, is clearly inappropriate. However, it is felt that a re-examination of the whole content of that genus is desirable before any proposals for taxonomic revisions are formulated.
Originally Cyclonephelium, subsequently (and now) Glaphyrocysta.
The name Cyclonephelium pastielsii was not validly published in Deflandre and Cookson (1955, p.285) since these authors did not provide a description or a direct reference to one (as required after 1952 by ICBN Article 32.3).
Holotype: Pastiels, 1948, pl.5, fig.15, as Membranilarnax cf. liradiscoidea; Fauconnier and Masure, 2004, pl.33, fig.9.
Age: Early Eocene.
Translation Pastiels, 1948, p. 47: LPP
Description: Pastiels, 1948, p. 47: Membranilarnax cf. liradiscoides O. Wetzel
Central capsule lenticular, ornamented in the equatorial region with radiating appendices, simple or bifurcate, joined distally by a network of tubular ramifications forming largely areolate meshes. The reproduction of the plate description of M. cf. liradiscoides, given by O. Wetzel, 1933, pl.6, fig. 3-4, is too incomplete to attribute this specimen to that species.
Diameter of the capsule 50 µm, total diameter approximately 80 µm.
Eaton, 1976, p. 259: Cyclonephelium pastielsii
Dimensions: Holotype: cyst body (without operculum) 53 x 57 Ám; length of processes up to 30 Ám.
Remarks: As in the case of Cyclonephelium exuberans, Deflandre & Cookson (1955: 285) also failed to designate a holotype for Cyclonephelium pastielsi, their new species name for forms described from the Lower Eocene of Belgium by Pastiels (1948) as Membranilarnax cf. Iiradiscoides 0. Wetzel 1933. However, since he only provided one illustration of M. cf. Iiradiscoides (Pastiels 1948: pl. 5, fig. 15, a probable camera lucida drawing) this must be the holotype, and it is here designated as such. Pastiels" original description of this form (1948: 47) indicates that it consists of a central body with processes restricted to the peripheral zone. The processes are simple or bifurcate, distally ramified and interconnected, and the illustrated specimen is devoid of them on reflected precingular plates 3"" and 6"".
In overall form the specimen illustrated by Pastiels is more closely comparable to Cyclonephelium retiintextum Cookson 1965 (De Coninck 1968: 41) than C. exuberans (Williams & Downie 1966: 225, 227). On this basis, C. pastielsi can only be considered to have been recorded from the Lower Eocene of Belgium (Pastiels 1948, as M. cf. Iiradiscoides; De Coninck 1965, 1968, Gruas-Cavagnetto 1968) and of northern France (Gruas-Cavagnetto 1968, 1970(b)). There are also several listed records without illustration or description which cannot be commented on: Lower Eocene of Belgium (De Coninck 1967), of northern France (Chateauneuf & Gruas-Cavagnetto 1968) and of the Hampshire Basin in southern England (Gruas-Cavagnetto 1970(a)); Middle Eocene of northern France (Gruas-Cavagnetto 1971).
Emended diagnosis: Sarjeant, 1986, p. 27-29: Glaphyrocysta pastielsii
Cyst lenticular, marginate and trabeculate. Ambitus broadly ovoidal, but with an asymmetrically situated antapical outbulge or broad, low horn (situated always to the left of the antapical pole in ventral view). Low surficial lines in the circumferential area may mark the positions of parasutures or may be lacking; normally the cingulum can be seen clearly only in the lateral regions. The mid-ventral and mid-dorsal regions lack ornament. Processes arise primarily or entirely from paraplate boundaries both in gonal and sutural positions. Their spacing is irregular, two to four parallel processes often arising close to a paraplate junction while the central sutural area lacks processes. They are short (in length, less than 1/3 the equatorial diameter of the cyst), very slender and apparently solid. The processes are linked distally by major trabeculae developed parallel to the paraplate boundaries. In addition meshworks of minor trabeculae may develop from the processes extending outward to join the major trabeculae and forming arch-like traceries beneath them. These meshworks are produced by the bifurcation or ramification the processes at about one-third height, the resultant branches being complexly interconnected. Archaeopyle apical, type (tA); sulcal notch and accessory sutures well marked. Operculum free.
Dimensions: Holotype: overall length 181 µm, length of central body (apex lacking) 48 µm, overall breadth 93 µm, breadth of central body 57 µm.
Discussion: A re-examination of the specimen figured by Pastiels (1948, pl. 5, fig. 15) shows his interpretative drawing to be, though correct enough in its major features, somewhat misleading in detail, the shape of the central body being less broad proportionately and the antapical prominence less evident than in reality. Moreover, the processes and the trabeculae are drawn too thick and their pattern of interconnexions is much simplified. The specimen illustrated as C. pastielsii by Williams and Downie (1966, pl. 25, fig. 2) does not appear to belong to this species. Although the photograph presented by Gocht (1969, pl. 8, fig. 15) provides a better basis for the interpretation of the morphology of this species, it is questionable whether, with these very different illustrations to serve as bases, subsequent identifications of this species have been correct.
Unfortunately, this is difficult to check since, in the majority of instances, no photographs are furnished in these later publications.
On the basis of these published records, Claphyrocysta pastielsii appears to have a stratigraphic range from Late Palaeocene (Thanetian) to Late Eocene (Bartonian); the few later records all appear doubtful. It has been reported from Belgium, the Netherlands, England, France, Germany, Italy, and from submarine cores from the Grand Banks and Scotian Shelf, offshore eastern Canada. The specimen from Spain illustratcd by Caro (1973) seems likely to prove attributable to a different species; and the systematic attribution of the specimens illustrated by De Coninck (1975) and Weiler (1980)) was properly regarded as questionable from the outset.
In their diagnosis of Glaphyrocysta, Stover and Evitt (1978, p. 69) noted that it has "No parasutural features." In the type species, G. retiinteeta (Cookson, 1965) Stover and Evitt, 1978, this may well be the case. However, the processes of G. pastielsii furnish a direct expression of the paratabulation, for they arise from parasutures (feebly marked or not at all) whose position is paralleled by the major trabeculae. In combination, these features permit the determination of a ceratioid paratabulation comparable (for instance) with that illustrated for Endoceratium ludbrookiae by Wall and Evitt (1975, text-fig. 9 D-E). The clear delimitation of the antapical paraplate (1"""") may be seen (pl. II, figs. 1, 3) and the enlarged illustrations here provided show how the boundaries of paraplates 4""" (Pl. II, fig. 5) and paraplate 2"" (Pl. II, fig. 4) can be distinguished without great difficulty. The displacement to the right of the bare midventral area (seen by transparency in pl. II, fig. 3) should also be noted. All in all, though the interpretation of the paratabulation in this species is difficult, it is by no means impossible. Since C. pastielsii thus has interconnected sutural processes rather than penitabular process complexes, its placement into the genus Glaphyrocysta, as presently defined, is clearly inappropriate. However, it is felt that a re-examination of the whole content of that genus is desirable before any proposals for taxonomic revisions are formulated.