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Tenua anaphrissa
From Fensome et al., 2019:
Tenua anaphrissa (Sarjeant, 1966c, p.206, pl.22, fig.8; pl.23, fig.6; text-fig.55) Benedek, 1972, p.9–10.
Emendation: Harding, 1990b, p.17–18, as Pseudoceratium anaphrissum.
Holotype: Sarjeant, 1966c, pl.22, fig.8; text-fig.55; Fensome et al., 2019a, fig.17M.
Originally Doidyx, subsequently (and now) Tenua Eisenack, thirdly Aptea, fourthly Pseudoceratium.
Fensome et al. (2019a, p.45) retained this species in Tenua Eisenack.
Taxonomic junior synonym: Cyclonephelium distinctum subsp. longispinatum (al. Cyclonephelium longispinatum), according to Fensome et al. (2019a, p.45–46).
Age: early Barremian.
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Original diagnosis: Sarjeant 1966, p. 206-207: Doidyx anaphrissa
A Doidyx having a asymmetrical biconical shell with short, blunt apical horn and with low bump on antapex. Spines simple, capitate or briefly bifurcate. Portion thrown off in archaeopyle formation exceeding one-third of shell length.
Dimensions: Holotype-overall length 105 µm, breadth 118 µm; shell length 110 µm, breadth 102 µm; spines c. 7 µm long. Range of dimensions: overall lengths c. 120-145 µm, breadths c. 105-130 µm.
Original description: Sarjeant 1966, p. 206-207: Doidyx anaphrissum
This species is moderately abundant, some 25 specimens having been encountered; complete shells were infrequent, detached apices and shells lacking an apex being commoner. The shell is approximately club-shaped: its asymmetry is so pronounced that a longitudinal division would leave some 60% on one side, some 40% on the other. The epitract slopes smoothly into the apical horn; the hypotract is surmounted by an antapical bulge of small height and larger amplitude. The surface is very minutely granular. There is a dense cover of short spines, most often capitate, less frequently evexate, oblate, bifid or bifurcate: these sometimes suggest arrangement into lines, but no coherent pattern was determined. An equatorial belt of moderate breadth, corresponding to the cingulum, lacks spines: a sulcus is not distinguishable. The holotype shows fission to form an archaeopyle, which has however, not become detached. Its margin is distinctly angular, suggesting a tabulation pattern not otherwise indicated.
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Comments Fensome et al., 2019a:
Sarjeant (1966, p. 207) erected Doidyx anaphrissa and noted that it has:
… a dense cover of short spines, most often capitate, less frequently evexate, oblate, bifid or bifurcate: these sometimes suggest arrangement into lines, but no coherent pattern was determined. An equatorial belt... corresponding to the cingulum, lacks spines.
The equatorial belt that, according to Sarjeant (1966), is devoid of spines is more apparent on his interpretative drawing than on his photographs, and we do not consider this constitutes a dorsoventral area devoid of ornament. We retain this species in Tenua as we consider Doidyx to be a taxonomic junior synonym of Tenua. This species accommodates forms of Tenua with slender, sometimes hair-like processes typically 4–10 μm long. Tenua hystrix has shorter, generally stubbier processes. The ambital outline of both species, as conceived herein, is variable.2593
In proposing Cyclonephelium distinctum subsp. longispinatum (subsequently Cyclonephelium longispinatum), Davey (1978, p. 894) noted that it was “… a subspecies … having a denser covering of long spines [presumably in comparison with the type subspecies?] which extend well on to the dorsal and ventral surfaces leaving only small areas devoid of processes”. Because of its lack of dorsoventral areas clearly devoid of ornament and its hair-like processes, we consider this taxon to be a taxonomic junior synonym of from Tenua anaphrissa.
Stratigraphical occurrence. Sarjeant (1966) described Doidyx anaphrissa from the lower Barremian of Yorkshire, England. Costa & Davey (1992) plotted the FAD of this species near the base of the early Barremian and its LAD within the earliest late Barremian. The type material of Cyclonephelium distinctum subsp. longispinatum is from the Turonian of offshore southwestern Africa.
Tenua anaphrissa (Sarjeant, 1966c, p.206, pl.22, fig.8; pl.23, fig.6; text-fig.55) Benedek, 1972, p.9–10.
Emendation: Harding, 1990b, p.17–18, as Pseudoceratium anaphrissum.
Holotype: Sarjeant, 1966c, pl.22, fig.8; text-fig.55; Fensome et al., 2019a, fig.17M.
Originally Doidyx, subsequently (and now) Tenua Eisenack, thirdly Aptea, fourthly Pseudoceratium.
Fensome et al. (2019a, p.45) retained this species in Tenua Eisenack.
Taxonomic junior synonym: Cyclonephelium distinctum subsp. longispinatum (al. Cyclonephelium longispinatum), according to Fensome et al. (2019a, p.45–46).
Age: early Barremian.
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Original diagnosis: Sarjeant 1966, p. 206-207: Doidyx anaphrissa
A Doidyx having a asymmetrical biconical shell with short, blunt apical horn and with low bump on antapex. Spines simple, capitate or briefly bifurcate. Portion thrown off in archaeopyle formation exceeding one-third of shell length.
Dimensions: Holotype-overall length 105 µm, breadth 118 µm; shell length 110 µm, breadth 102 µm; spines c. 7 µm long. Range of dimensions: overall lengths c. 120-145 µm, breadths c. 105-130 µm.
Original description: Sarjeant 1966, p. 206-207: Doidyx anaphrissum
This species is moderately abundant, some 25 specimens having been encountered; complete shells were infrequent, detached apices and shells lacking an apex being commoner. The shell is approximately club-shaped: its asymmetry is so pronounced that a longitudinal division would leave some 60% on one side, some 40% on the other. The epitract slopes smoothly into the apical horn; the hypotract is surmounted by an antapical bulge of small height and larger amplitude. The surface is very minutely granular. There is a dense cover of short spines, most often capitate, less frequently evexate, oblate, bifid or bifurcate: these sometimes suggest arrangement into lines, but no coherent pattern was determined. An equatorial belt of moderate breadth, corresponding to the cingulum, lacks spines: a sulcus is not distinguishable. The holotype shows fission to form an archaeopyle, which has however, not become detached. Its margin is distinctly angular, suggesting a tabulation pattern not otherwise indicated.
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Comments Fensome et al., 2019a:
Sarjeant (1966, p. 207) erected Doidyx anaphrissa and noted that it has:
… a dense cover of short spines, most often capitate, less frequently evexate, oblate, bifid or bifurcate: these sometimes suggest arrangement into lines, but no coherent pattern was determined. An equatorial belt... corresponding to the cingulum, lacks spines.
The equatorial belt that, according to Sarjeant (1966), is devoid of spines is more apparent on his interpretative drawing than on his photographs, and we do not consider this constitutes a dorsoventral area devoid of ornament. We retain this species in Tenua as we consider Doidyx to be a taxonomic junior synonym of Tenua. This species accommodates forms of Tenua with slender, sometimes hair-like processes typically 4–10 μm long. Tenua hystrix has shorter, generally stubbier processes. The ambital outline of both species, as conceived herein, is variable.2593
In proposing Cyclonephelium distinctum subsp. longispinatum (subsequently Cyclonephelium longispinatum), Davey (1978, p. 894) noted that it was “… a subspecies … having a denser covering of long spines [presumably in comparison with the type subspecies?] which extend well on to the dorsal and ventral surfaces leaving only small areas devoid of processes”. Because of its lack of dorsoventral areas clearly devoid of ornament and its hair-like processes, we consider this taxon to be a taxonomic junior synonym of from Tenua anaphrissa.
Stratigraphical occurrence. Sarjeant (1966) described Doidyx anaphrissa from the lower Barremian of Yorkshire, England. Costa & Davey (1992) plotted the FAD of this species near the base of the early Barremian and its LAD within the earliest late Barremian. The type material of Cyclonephelium distinctum subsp. longispinatum is from the Turonian of offshore southwestern Africa.