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Evansia granulata
From Fensome et al., 2019:
Evansia granulata Pocock, 1972, p.95, pl.24, fig.7; text-fig.12. Holotype: Pocock, 1972, pl.24, fig.7; Jansonius, 1986, pl.5, figs.1–3; text-figs.10a–b. Originally (and now) Evansia, subsequently Glomodinium. Lentin and Williams (1993, p.215) retained this species in Evansia. Age: late Bajocian.
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Original description: Pocock, 1972, p.95
Vesicle dorso-ventrally flattened; outline oval with short projecting apical horn; archeopyle intercalary with simple free operculum; no plating visible; transverse and longitudinal furrows not detectable; theca two-layered comprising an inner smoothly rounded capsule about 0.5 µm thick overlain by a tightly enveloping outer granulose layer 1.0-1.5 µm thick; finely and closely granulose, giving the surface a spongy appearance; apical horn solid; about 10.0 µm Iong; antapically a small process about 2.0 µm long formed by thickening of the outer layer; colourless; theca 58.3x40.7 µm; capsule 44.0x37.4 µm.
Supplemental description: Jansonius, 1986, p.210
(Holotype) 58.5 x 42 µm overall, dorsal face up. Wall consisting of a proportionally thin hyaline inner layer (0.3-0.4 µm), overlain by a granulose-spongy outer layer, individual granules (in part extended into spinules, rods or clavae) up to 1.5 µm tall, but generally not much more (or less) than 1 µm. The granular layer is more or less reduced over the apical horn, which carries some thin cilia near its tip. Dorsal side showing a nearly square, weakly hexagonal 2a plate faintly delineated by a narrow groove cutting through the granular outer layer; its angled adcingular delineation passes over the lower part of a nucleus inside the grain (chromatophores?); the angled anterior margins of la and 3a are only barely differentiated. The cingulum is incompletely indicated by a small bulge and slightly reduced granular layer on the left margin, a tear on the right margin, and a vague groove connecting these two features. No other paratabulation can be discerned except for a rudimentary right antapical process, and a slightly thinned ventral sulcal area. Because of folding of an original near-spherical body with a thin wall, several large crescentic folds are produced; the largest of these lies under the intercalary plates, and suggests the presence of a spherical inner body. This is an illusion however; the central cavity is continuous into the apical horn.
Evansia granulata Pocock, 1972, p.95, pl.24, fig.7; text-fig.12. Holotype: Pocock, 1972, pl.24, fig.7; Jansonius, 1986, pl.5, figs.1–3; text-figs.10a–b. Originally (and now) Evansia, subsequently Glomodinium. Lentin and Williams (1993, p.215) retained this species in Evansia. Age: late Bajocian.
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Original description: Pocock, 1972, p.95
Vesicle dorso-ventrally flattened; outline oval with short projecting apical horn; archeopyle intercalary with simple free operculum; no plating visible; transverse and longitudinal furrows not detectable; theca two-layered comprising an inner smoothly rounded capsule about 0.5 µm thick overlain by a tightly enveloping outer granulose layer 1.0-1.5 µm thick; finely and closely granulose, giving the surface a spongy appearance; apical horn solid; about 10.0 µm Iong; antapically a small process about 2.0 µm long formed by thickening of the outer layer; colourless; theca 58.3x40.7 µm; capsule 44.0x37.4 µm.
Supplemental description: Jansonius, 1986, p.210
(Holotype) 58.5 x 42 µm overall, dorsal face up. Wall consisting of a proportionally thin hyaline inner layer (0.3-0.4 µm), overlain by a granulose-spongy outer layer, individual granules (in part extended into spinules, rods or clavae) up to 1.5 µm tall, but generally not much more (or less) than 1 µm. The granular layer is more or less reduced over the apical horn, which carries some thin cilia near its tip. Dorsal side showing a nearly square, weakly hexagonal 2a plate faintly delineated by a narrow groove cutting through the granular outer layer; its angled adcingular delineation passes over the lower part of a nucleus inside the grain (chromatophores?); the angled anterior margins of la and 3a are only barely differentiated. The cingulum is incompletely indicated by a small bulge and slightly reduced granular layer on the left margin, a tear on the right margin, and a vague groove connecting these two features. No other paratabulation can be discerned except for a rudimentary right antapical process, and a slightly thinned ventral sulcal area. Because of folding of an original near-spherical body with a thin wall, several large crescentic folds are produced; the largest of these lies under the intercalary plates, and suggests the presence of a spherical inner body. This is an illusion however; the central cavity is continuous into the apical horn.