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Gonyaulacysta pennata
Gonyaulacysta pennata Riley in Fisher and Riley, 1980
Now Rhynchodiniopsis. Originally Gonyaulacysta, subsequently Hystrichogonyaulax, thirdly Millioudodinium, fourthly (and now) Rhynchodiniopsis.
This species name was a nomen nudum in Fisher and Riley, 1976, who did not provide a description or illustration.
Holotype: Fisher and Riley, 1980, pl.1, figs.10-11; Jan du Chêne et al., 1986, pl.98, fig.5
Locus typicus: Argiles de Wimereux, Boulonais, France
Stratum typicum: Late Kimmeridgian
Original diagnosis: Riley, 1980, p.321
A species of Gonyaulacysta with an elongate-ovoidal cyst. Apex tapering to form a strong, abruptly rounded apical horn of varying length bearing a feather-like expansion formed from periphragm only. Plate boundaries indicated by low ridge formed from the periphragm, from which arise spines, either simple and isolated or confluent, particularly in the antapical region, to form a loosely constructed sutural net-like structure up to 5 Ám heigth. Cingulum relatively narrow, dividing the cyst unequally, epitract larger than hypotract. Sulcus long and narrow, extending into both epitract and hypotract. Cyst wall thick, two-layered, densely, but finely granular and irregularly perforate.
Dimensions: Holotype - overall length 84 Ám, breadth 47 Ám, length of apical horn 5 Ám, length pf feather-like apical extension 12 Ám, heigth of sutural-crests, up to 5 Ám. Range: overall length 75-93 Ám, breadth 47-68 Ám.
Affinities:
Riley, 1980, p.321
G. pennata differs from all previously described species of Gonyaulacysta by the combination of its distinctive sutural ornamentation and apical structure.
Now Rhynchodiniopsis. Originally Gonyaulacysta, subsequently Hystrichogonyaulax, thirdly Millioudodinium, fourthly (and now) Rhynchodiniopsis.
This species name was a nomen nudum in Fisher and Riley, 1976, who did not provide a description or illustration.
Holotype: Fisher and Riley, 1980, pl.1, figs.10-11; Jan du Chêne et al., 1986, pl.98, fig.5
Locus typicus: Argiles de Wimereux, Boulonais, France
Stratum typicum: Late Kimmeridgian
Original diagnosis: Riley, 1980, p.321
A species of Gonyaulacysta with an elongate-ovoidal cyst. Apex tapering to form a strong, abruptly rounded apical horn of varying length bearing a feather-like expansion formed from periphragm only. Plate boundaries indicated by low ridge formed from the periphragm, from which arise spines, either simple and isolated or confluent, particularly in the antapical region, to form a loosely constructed sutural net-like structure up to 5 Ám heigth. Cingulum relatively narrow, dividing the cyst unequally, epitract larger than hypotract. Sulcus long and narrow, extending into both epitract and hypotract. Cyst wall thick, two-layered, densely, but finely granular and irregularly perforate.
Dimensions: Holotype - overall length 84 Ám, breadth 47 Ám, length of apical horn 5 Ám, length pf feather-like apical extension 12 Ám, heigth of sutural-crests, up to 5 Ám. Range: overall length 75-93 Ám, breadth 47-68 Ám.
Affinities:
Riley, 1980, p.321
G. pennata differs from all previously described species of Gonyaulacysta by the combination of its distinctive sutural ornamentation and apical structure.