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Gonyaulacysta granulata

Gonyaulacysta granulata "granulata" (Klement, 1960, p.39-41, pl.4, figs.10-13; text-figs.18-20) Sarjeant, 1969, p.9. Emendation: Sarjeant, 1984a, p.161-162, as Meristaulax granulata.

NOW Cribroperidinium. Originally Gonyaulax (motile stage), subsequently Gonyaulacysta, thirdly (and now) Cribroperidinium, fourthly Rhynchodiniopsis, fifthly Meristaulax Sarjeant, sixthly Acanthaulax. Poulsen (1996, p.73) retained this species in Cribroperidinium.
Taxonomic junior synonyms: Gonyaulax (as Cribroperidinium) venusta, according to Schrank (2005, p.56); Gonyaulax (now Cribroperidinium) granuligera, according to Fisher and Riley (1980, p.321) — however, Sarjeant (1984a, p.156–158) retained Gonyaulax (as Cryptarchaeodinium) granuligera; Gonyaulacysta (as Acanthaulax?, now Cribroperidinium) angulosa, according to Fisher and Riley (1980, p.321) — however, Sarjeant and Gocht in Sarjeant (1984a, p.160) retained Gonyaulacysta (as Meristaulax) angulosa. For further discussion, see Cribroperidinium granulatum.

Holotype: Klement, 1960, pl.4, figs.10–11; text-figs.18–20; Fensome et al., 1995, figs.1–2 — p.1525; disintegrated according to Sarjeant (1984a, p.162).
Lectotype (designated by Sarjeant, 1984a, p.162): Sarjeant, 1984a, pl.3, figs.3–4; text-fig.3; Jan du Chêne et al., 1986a, pl.27, figs.7–10; Brenner, 1988, pl.3, figs.2a–b; Fensome et al., 1995, figs.5–6 — p.1525 — however, Brenner (1988, p.35) argued that this specimen is not conspecific with the holotype.
Lectotype (designated by Brenner, 1988, p.35): Brenner, 1988, pl.1, figs.3a–c; Fensome et al., 1995, figs.7–9 — p.1525.
Age: Mid Oxfordian-Early Kimmeridgian.

Supplemental description: Gitmez, 1970, p.255-256
The broadly spherical shell is divided into two almost equal parts by the laevorotatory cingulum. A short apical horn is present. Tabulation: 4", 6", 6c, 6""", 1p and 1"""". Moderately low sutures rise up on the plate boundaries. Sulcus is short and broad. The precingular archaeopyle forms through loss of the plate 3". Surface of the shell finely granular.
Dimensions: Figured specimen: overall length 62 Ám, breadth 55 Ám; horn length 7 Ám. Other French specimens (15 specimens measured): overall length 62-80 Ám, breadth 55-65 Ám; horn length 6-7 Ám. Range of the English specimens (2 specimens measured) : overall length 68-73 Ám, breadth 70-72 Ám; horn length 6-8 Ám. (Dimensions of the type material: length 66 Ám, breadth 63 Ám; horn length 9 Ám.

Taxonomic note: Lentin and Williams, 1993, p. 250:
According to Brenner, 1988, the specimen designated as the lectotype by Sarjeant, 1984, cannot be a lectotype since it is not from the same sample as the holotype.
As defined in I.C.B.N. Article 7.5, a lectotype is selected from the original material. Whether this has to be the same sample is not made clear. Brenner, 1988, also reasoned that the morphology of the lectotype, as designated by Sarjeant, 1984, of Acanthaulax granulata differed sufficiently from the holotype to represent a new species. I.C.B.N. Article 8.1 states that the choice of a lectotype by an author may be superseded if it can be shown to be in serious conflict with the protologue. Brenner, 1988, designated as the lectotpye the specimen illustrated in Brenner, 1988, pl.1, figs.3a-c. Further, Brenner, 1988, give the citation Meristaulax granulata sensu Sarjeant, 1984 and listed the holotype as Sarjeant, 1984, pl.3, figs.3-4.
Now Acanthaulax. Originally Gonyaulax, subsequently Gonyaulacysta, thirdly Cribroperidinium, fourthly Rhynchodiniopsis, fifthly Meristaulax, sixthly (and now) Acanthaulax.
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