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Senoniasphaera filoreticulata
From Fensome et al., 2019:
(Slimani, 1994, p.96–97, pl.15, figs.1–6) Fensome et al., 2019a, p.42. Holotype: Slimani, 1994, pl.15, figs.1–4; Fensome et al., 2019a, figs.16I–L. Originally Canningia, subsequently Cyclonephelium, thirdly (and now) Senoniasphaera. Age: early–late Campanian.
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Original description (Slimani, 1994) Translated PKB 2024:
Derivation of the name: Latin: filosa: fibrous; repressants: reticulated; reference to fibrous processes and septa and reticulated fectophragma.
Holotvpe: Beutenaken ech. 4, preparation 5, coordinate. E.F.X24.
Paratvpe: Halembaye ech. 4, preparation 3. coordination. E.F. U25/2.
Type locality: Beutenaken ex. 4.
Horizon type: Upper Campanian. (Member of Zeven Wegen).
Diagnosis: Canningia cyst, lenticular, with two antapical protrusions, the left one of which is often better expressed. It is characterized by a reticulate ectophragm supported by fibroreticulate processes and septa, fairly spaced and reaching a height of approximately 1/5 of the total diameter. With the exception of the archaeopyle, paratabulation is apparently absent.
Dimensions: Holotype: ectocyst, length: 80, width: 100 µm; endocyst, length: 58, width: 60 µm. Variations: ectocyst, length: 60 - 90, width: 60 -100 µm; endocyst, length: 48 - 70, width: 40 - 64 µm. Height of septa and processes: 8 - 20 µm. Process width 1.5-10 µm. Length of the left antapical horn: approximately 10 µm. Measurements were made on 18 specimens without operculum. Material: 40 copies.
Description: In this species the lateral edges are slightly rounded in the equatorial region. The autophragm is smooth to weakly granulated and has a thickness which varies around 1 µm. The processes and septa are 1 to 4 µm thick. fibrous to reticulate and strongly flared distally. The septa and processes are widely spaced 10 to 40 µm apart and connected proximally by low ridges that give the cyst surface a largely sinuous and irregular appearance. The central part of the ventral surface is often devoid of processes and septa. The ectophragm is more or less continuous and generally has the same shape as the central body from which it is uniformly separated.
The reticle meshes are circular, oval, or polygonal with a diameter that varies between 0.5 and 8 µm; the widest ones are aligned forming more or less fragile zones partially interrupting the ectophragm. These zones may correspond to parasutural zones which are not clearly expressed. The archaeopyle is apical (tA) type with a zigzag margin showing a small sulcal-notch and the anterior edge of six precingulate paraplates: the operculum is free.
Comparison: Canningia filoreticuiata sp. nov. is characterized by the sinuous appearance of the surface of the cyst and by its reticulated ectophragm which recalls Eatonicysta ursulae (Morgenroth, 1966a) Stover and Evitt (1978). Especially by its lenticular shape, by the presence of antapical protrusions and by the type of structures supporting the ectophragm, the present species is distinguished from E. ursulae. Its structure also recalls Pterocystidiopsis ornata Deflandre (1937b) and also the specimen called Membranilarnacia cf. ursulae by Foucher (197 lb: p. 102; pl. 8; fig. 6,7), from the Coniacian (Pas-de-Calais, France), two forms but known. The species studied bears little resemblance to the Belgian Paleocene specimens determined as Eatonicysta ursulae by Schumacker - Lambry and Chateneuf (1976: pl.3; fig. 6, 7), the same specimens were later attributed to Cyclonephelium conopium Denison uned. by Schumacker-Lambry (1978: p39; pl. 3; fig. 9, 10). Canningia spongucnculata Prössl (1990) has the same appearance as Canningia filoreticuiata sp. nov. but differs by the presence of a clear paratabulation and by its smooth or porous ectophragm supported only by septa. The endophragm and ectophragm in Canningia transitoria Stover and Helby (1987d) are also quite separate, but they are more spaced apart at the level of lateral and antapical protrusions, paratabulation in this species is clear. Canningia grandis Helby (1987) presents a greater number of structures supporting the ectophragm. Canningia recticulata Cookson and Eisenack (1960b) has an ectophragm and endophraome that are much less spaced apart and connected by a much greater number of fine structures.
Stratigraphic distribution:
Beutenaken: ex. 1 to 10, Halembaye: ex. 4 to 25; Lower Campanian - Upper Campanian. (Zone with G. quadrata – Zone with B. mucronata. Turnhout: -987 to -966.50 m, Lower Campanian - Upper Campanian.
(Slimani, 1994, p.96–97, pl.15, figs.1–6) Fensome et al., 2019a, p.42. Holotype: Slimani, 1994, pl.15, figs.1–4; Fensome et al., 2019a, figs.16I–L. Originally Canningia, subsequently Cyclonephelium, thirdly (and now) Senoniasphaera. Age: early–late Campanian.
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Original description (Slimani, 1994) Translated PKB 2024:
Derivation of the name: Latin: filosa: fibrous; repressants: reticulated; reference to fibrous processes and septa and reticulated fectophragma.
Holotvpe: Beutenaken ech. 4, preparation 5, coordinate. E.F.X24.
Paratvpe: Halembaye ech. 4, preparation 3. coordination. E.F. U25/2.
Type locality: Beutenaken ex. 4.
Horizon type: Upper Campanian. (Member of Zeven Wegen).
Diagnosis: Canningia cyst, lenticular, with two antapical protrusions, the left one of which is often better expressed. It is characterized by a reticulate ectophragm supported by fibroreticulate processes and septa, fairly spaced and reaching a height of approximately 1/5 of the total diameter. With the exception of the archaeopyle, paratabulation is apparently absent.
Dimensions: Holotype: ectocyst, length: 80, width: 100 µm; endocyst, length: 58, width: 60 µm. Variations: ectocyst, length: 60 - 90, width: 60 -100 µm; endocyst, length: 48 - 70, width: 40 - 64 µm. Height of septa and processes: 8 - 20 µm. Process width 1.5-10 µm. Length of the left antapical horn: approximately 10 µm. Measurements were made on 18 specimens without operculum. Material: 40 copies.
Description: In this species the lateral edges are slightly rounded in the equatorial region. The autophragm is smooth to weakly granulated and has a thickness which varies around 1 µm. The processes and septa are 1 to 4 µm thick. fibrous to reticulate and strongly flared distally. The septa and processes are widely spaced 10 to 40 µm apart and connected proximally by low ridges that give the cyst surface a largely sinuous and irregular appearance. The central part of the ventral surface is often devoid of processes and septa. The ectophragm is more or less continuous and generally has the same shape as the central body from which it is uniformly separated.
The reticle meshes are circular, oval, or polygonal with a diameter that varies between 0.5 and 8 µm; the widest ones are aligned forming more or less fragile zones partially interrupting the ectophragm. These zones may correspond to parasutural zones which are not clearly expressed. The archaeopyle is apical (tA) type with a zigzag margin showing a small sulcal-notch and the anterior edge of six precingulate paraplates: the operculum is free.
Comparison: Canningia filoreticuiata sp. nov. is characterized by the sinuous appearance of the surface of the cyst and by its reticulated ectophragm which recalls Eatonicysta ursulae (Morgenroth, 1966a) Stover and Evitt (1978). Especially by its lenticular shape, by the presence of antapical protrusions and by the type of structures supporting the ectophragm, the present species is distinguished from E. ursulae. Its structure also recalls Pterocystidiopsis ornata Deflandre (1937b) and also the specimen called Membranilarnacia cf. ursulae by Foucher (197 lb: p. 102; pl. 8; fig. 6,7), from the Coniacian (Pas-de-Calais, France), two forms but known. The species studied bears little resemblance to the Belgian Paleocene specimens determined as Eatonicysta ursulae by Schumacker - Lambry and Chateneuf (1976: pl.3; fig. 6, 7), the same specimens were later attributed to Cyclonephelium conopium Denison uned. by Schumacker-Lambry (1978: p39; pl. 3; fig. 9, 10). Canningia spongucnculata Prössl (1990) has the same appearance as Canningia filoreticuiata sp. nov. but differs by the presence of a clear paratabulation and by its smooth or porous ectophragm supported only by septa. The endophragm and ectophragm in Canningia transitoria Stover and Helby (1987d) are also quite separate, but they are more spaced apart at the level of lateral and antapical protrusions, paratabulation in this species is clear. Canningia grandis Helby (1987) presents a greater number of structures supporting the ectophragm. Canningia recticulata Cookson and Eisenack (1960b) has an ectophragm and endophraome that are much less spaced apart and connected by a much greater number of fine structures.
Stratigraphic distribution:
Beutenaken: ex. 1 to 10, Halembaye: ex. 4 to 25; Lower Campanian - Upper Campanian. (Zone with G. quadrata – Zone with B. mucronata. Turnhout: -987 to -966.50 m, Lower Campanian - Upper Campanian.