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Evansia alaskensis
From Fensome et al., 2019:
Evansia alaskensis (Wiggins, 1975, p.104, pl.2, figs.7–8) Below, 1990, p.72. Holotype: Wiggins, 1975, pl.2, fig.7. Originally Pareodinia, subsequently Glomodinium (combination not validly published), thirdly (and now) Evansia. Taxonomic junior synonyms: Pareodinia minuta and Pareodinia robusta, both according to Below (1990, p.72) —however, Poulsen (1996, p.62) retained Pareodinia robusta. Below (1990, p.65) suggested that Pareodinia arctica may be a smooth variant of this species. Age: ?Callovian–middle Kimmeridgian.
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Original diagnosis: Wiggins, 1975, p. 104: Pareodinia alaskensis
Proximate fossil cysts, ambitus ovoidal. Epitract and hypotract approximately equal, divided by a faint to moderately distinct girdle. Cyst exhibits a distinct apical horn and a broadly rounded antapex. Reflected tabulation faint, but noted occasionally on the epitract and hypotract. Archeopyle intercalary, Type 3I, and operculum composed of 3 nearly equalsized plates. Cyst wall coarsely granulate to verrucose, and ornamentation equally distributed over entire wall surface. Apicular structure present in the form of a short, rod-like, finely granulose thickening.
Dimensions. Holotype, 45x78 µm, paratype 44x90 µm.
Affinities:
Wiggins, 1975, p. 104: Pareodinia alaskensis
This species resembles Pareodinia kondratjevi, but the cyst wall of P. alaskensis is noticeably thicker and its apical morphology is different.
Evansia alaskensis (Wiggins, 1975, p.104, pl.2, figs.7–8) Below, 1990, p.72. Holotype: Wiggins, 1975, pl.2, fig.7. Originally Pareodinia, subsequently Glomodinium (combination not validly published), thirdly (and now) Evansia. Taxonomic junior synonyms: Pareodinia minuta and Pareodinia robusta, both according to Below (1990, p.72) —however, Poulsen (1996, p.62) retained Pareodinia robusta. Below (1990, p.65) suggested that Pareodinia arctica may be a smooth variant of this species. Age: ?Callovian–middle Kimmeridgian.
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Original diagnosis: Wiggins, 1975, p. 104: Pareodinia alaskensis
Proximate fossil cysts, ambitus ovoidal. Epitract and hypotract approximately equal, divided by a faint to moderately distinct girdle. Cyst exhibits a distinct apical horn and a broadly rounded antapex. Reflected tabulation faint, but noted occasionally on the epitract and hypotract. Archeopyle intercalary, Type 3I, and operculum composed of 3 nearly equalsized plates. Cyst wall coarsely granulate to verrucose, and ornamentation equally distributed over entire wall surface. Apicular structure present in the form of a short, rod-like, finely granulose thickening.
Dimensions. Holotype, 45x78 µm, paratype 44x90 µm.
Affinities:
Wiggins, 1975, p. 104: Pareodinia alaskensis
This species resembles Pareodinia kondratjevi, but the cyst wall of P. alaskensis is noticeably thicker and its apical morphology is different.