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Doidyx anaphrissa
Doidyx anaphrissa Sarjeant, 1966; Emendation: Harding, 1990b, p.17-18, as Pseudoceratium anaphrissum.
Now Pseudoceratium. Originally Doidyx, subsequently Tenua Eisenack, 1958, thirdly Aptea, fourthly (and now) Pseudoceratium.
Holotype: Sarjeant, 1966, pl.22,fig.8, text-fig.55
Locus typicus: West Heslerton, Yorkshire, England
Stratum typicum: Early Barremian
Original diagnosis: Sarjeant 1966, p. 206-207
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 105m Á, breadth 118 Ám; shell length 110 Ám, breadth 102 Ám; spines c. 7 Ám long. Range of dimensions: overall lengths c. 120-145 Ám, breadths c. 105-130 Ám.
Original description: Sarjeant 1966, p. 206-207
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.
Now Pseudoceratium. Originally Doidyx, subsequently Tenua Eisenack, 1958, thirdly Aptea, fourthly (and now) Pseudoceratium.
Holotype: Sarjeant, 1966, pl.22,fig.8, text-fig.55
Locus typicus: West Heslerton, Yorkshire, England
Stratum typicum: Early Barremian
Original diagnosis: Sarjeant 1966, p. 206-207
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 105m Á, breadth 118 Ám; shell length 110 Ám, breadth 102 Ám; spines c. 7 Ám long. Range of dimensions: overall lengths c. 120-145 Ám, breadths c. 105-130 Ám.
Original description: Sarjeant 1966, p. 206-207
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.