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Areoligera microreticulata
From Fensome et al., 2019:
Areoligera microreticulata Slimani, 1994, p.93–94, pl.15, figs.13–15; pl.16, figs.9–12. Holotype: Slimani, 1994, pl.15,
figs.13–15; Fauconnier and Masure, 2004, pl.4, figs.1–3. Taxonomic junior synonym: Areoligera reticulata (name
not validly published), according to Slimani (2001a, p.192). Age: late Campanian.
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Original description: [Slimani, 1994] (translated from French):
Name Derivation:
Greek: micro, small; Latin: reticulatus, reticulate; referring to microreticulate processes.
Holotype:
Turnhout -933 m, preparation 3, E.F. coord. G49/1.
Type locality:
Turnhout -933 m.
Type horizon:
Upper Campanian
Synonymy:
?1974: Areoligera reticulata n. sp. in WLSON, pp. 303-304, pl. 35, fig. 4-6.
Diagnosis:
Areoligera cyst, lenticular to subspherical in shape. It is characterized by its periphragm and process complexes, which are typically microreticulate. The apex bears an apical protuberance. The antapex is often provided with two antapical protuberances, the left one being more or less pointed and more pronounced than the right one, which is weakly expressed or absent. The paratabulation is of the gonyaulacoid type, conforming to the formula: 4.6", 23c, 5"", 1 p, 1"*".
Dimensions:
Holotype: central body, length: 50 µm, width: 50 µm; entire cyst, length: 70 µm, width: 80 µm.
Variations: central body, length: 40-56, width: 47-60 µm; entire cyst, length: 44-70, width: 70-84 µm.
Number of specimens measured without operculum: 14.
Material:
> 14 specimens.
Description:
The endophragm is smooth to granulated. The periphragm is microreticulate, especially in the intratabular areas. The precingulate and postcingulate penitabular process complexes are arcuate or soleate. while the antapical complex is annular; these complexes begin proximally with microreticular or fenestrated membranous septa (perforations of 1-4 µm) that divide distally between half and three-quarters of their height, giving rise to simple or furcated processes with capitate, bifid, or acuminate distal ends. The lateral antapical processes are longer and more reticulate than the dorsal and paracingulate processes. The penitabular zones located between the process complexes are narrow. The archaeopyle is apical type (tA) with a zigzag margin and a free operculum.
Comparison:
The morphological characteristics of A. microreticulata sp. nov. correspond fairly well to the description of Areoligera reticulata in Wilson (1974: p. 303-304) from the Upper Campanian of the Maastricht region, but the images of the specimens shown by this author, in Plate 35, Figs. 4-6, are too obscure to verify a possible correspondence. A. volata Drugg (1967) is close to the studied species in its reticulate periphragm, but differs in its dorsal process complexes that are all annular, its lateral processes that are considerably longer and distally interconnected, and the absence of the antapical processes. While A. semicirculata (Morgenroth 1966b) and Stover and Evitt (1978) also has perforated process complexes but with a semicircular outline. Specimens of A. sp. Figured in Williams and Brideaux (1975) also show perforated process complexes but with indistinct outlines.
Stratigraphic distribution:
Halembaye: scales 25 to 33, Upper Campanian (B. minor Zone). Turnhout: -933 m, end of Upper Campanian.
Areoligera microreticulata Slimani, 1994, p.93–94, pl.15, figs.13–15; pl.16, figs.9–12. Holotype: Slimani, 1994, pl.15,
figs.13–15; Fauconnier and Masure, 2004, pl.4, figs.1–3. Taxonomic junior synonym: Areoligera reticulata (name
not validly published), according to Slimani (2001a, p.192). Age: late Campanian.
---------------------------------------------------------------------------------------------------
Original description: [Slimani, 1994] (translated from French):
Name Derivation:
Greek: micro, small; Latin: reticulatus, reticulate; referring to microreticulate processes.
Holotype:
Turnhout -933 m, preparation 3, E.F. coord. G49/1.
Type locality:
Turnhout -933 m.
Type horizon:
Upper Campanian
Synonymy:
?1974: Areoligera reticulata n. sp. in WLSON, pp. 303-304, pl. 35, fig. 4-6.
Diagnosis:
Areoligera cyst, lenticular to subspherical in shape. It is characterized by its periphragm and process complexes, which are typically microreticulate. The apex bears an apical protuberance. The antapex is often provided with two antapical protuberances, the left one being more or less pointed and more pronounced than the right one, which is weakly expressed or absent. The paratabulation is of the gonyaulacoid type, conforming to the formula: 4.6", 23c, 5"", 1 p, 1"*".
Dimensions:
Holotype: central body, length: 50 µm, width: 50 µm; entire cyst, length: 70 µm, width: 80 µm.
Variations: central body, length: 40-56, width: 47-60 µm; entire cyst, length: 44-70, width: 70-84 µm.
Number of specimens measured without operculum: 14.
Material:
> 14 specimens.
Description:
The endophragm is smooth to granulated. The periphragm is microreticulate, especially in the intratabular areas. The precingulate and postcingulate penitabular process complexes are arcuate or soleate. while the antapical complex is annular; these complexes begin proximally with microreticular or fenestrated membranous septa (perforations of 1-4 µm) that divide distally between half and three-quarters of their height, giving rise to simple or furcated processes with capitate, bifid, or acuminate distal ends. The lateral antapical processes are longer and more reticulate than the dorsal and paracingulate processes. The penitabular zones located between the process complexes are narrow. The archaeopyle is apical type (tA) with a zigzag margin and a free operculum.
Comparison:
The morphological characteristics of A. microreticulata sp. nov. correspond fairly well to the description of Areoligera reticulata in Wilson (1974: p. 303-304) from the Upper Campanian of the Maastricht region, but the images of the specimens shown by this author, in Plate 35, Figs. 4-6, are too obscure to verify a possible correspondence. A. volata Drugg (1967) is close to the studied species in its reticulate periphragm, but differs in its dorsal process complexes that are all annular, its lateral processes that are considerably longer and distally interconnected, and the absence of the antapical processes. While A. semicirculata (Morgenroth 1966b) and Stover and Evitt (1978) also has perforated process complexes but with a semicircular outline. Specimens of A. sp. Figured in Williams and Brideaux (1975) also show perforated process complexes but with indistinct outlines.
Stratigraphic distribution:
Halembaye: scales 25 to 33, Upper Campanian (B. minor Zone). Turnhout: -933 m, end of Upper Campanian.