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Spongodinium canadense

Spongodinium canadense Singh, 1983, p.141, pl.49, figs.1–3. Emendation: Lucas-Clark, 1987, p.164, as Wigginsiella canadensis.

Now Wigginsiella. Originally Spongodinium, subsequently (and now) Wigginsiella.
Holotype: Singh, 1983, pl.49, fig.1; Jan du Chêne et al., 1986, pl.114, fig.3
Paratypes: Singh, 1983
Locus typicus: Peace River area, Canada
Stratum typicum: Early Cenomanian

Original description: Singh, 1983, p. 141
Proximochorate cysts; body subrhomboidal to subspheroidal in lateral view and circular in apicalantapical view; body prolonged into a medium-sized, blunt apical horn, length of the apical horn about 1/4 of the length of the body; antapex with two low prominences surmounted by short bifid processes; cyst wall composed of vesicular autophragm with 1-3 µm wide alveoli; vesicular structure distinctly thicker along the paracingulum, antapical area, and at the base of the apical horn; parasutures incompletely indicated by narrow bands of slightly thicker vesiculate structure; rows of 3-5 µm long bifid processes lining the paracingulum and partially indicating the parasutures; paratabulation not clearly discernible, probably gonyaulacacean; paracingulum about 15 µm wide, delineated by two 8-10 µm high, parallel, transverse, equatorial flanges composed of vesicular structure and surmounted by short bifid processes; parasulcus indicated by an interruption in the paracingulum and a marked reduction in the thickness of the vesiculate structure of the autophragm; archeopyle precingular, type P (3" only); operculum free, sometimes remaining in place.
Size range: Overall length of the cyst including the apical horn 100(104)108 µm. Holotype 108 µm. Length of the body 72(76)80 µm. Holotype 80 µm. Breadth of the body 82(86)90 µm. Holotype 90 µm.
Equatorial diameter of the body in apical view 76(80)84 µm. Paratype 84 µm. Length of the apical horn 16(18)20 µm. Holotype 20 µm.
Width of the sulcus in the paracingular area 13(15)16 µm. Paratype 15 µm. Width of the paracingular flanges 8(9)10 µm. Paratype 8 to 10 µm.
Specimens measured 4.

Affinities:
Singh, 1983, p. 141: Spongodinium canadense is distinct from Spongodinium delitiense (Ehrenberg) Deflandre, 1936, which lacks the distinctive rows of short bifid processes on the paracingulum and parasutures and has larger alveoli in the vesiculate autophragm. S. delitiense does not occur in strata older than Campanian in age.
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