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Wigginsiella canadensis
From Fensome et al., 2019:
Wigginsiella canadensis (Singh, 1983, p.141, pl.49, figs.1–3) Lucas-Clark, 1987, p.164. Emendation: Lucas-Clark, 1987, p.164, as Wigginsiella canadensis.
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: Upper Shaftesbury Formation of the Peace River area
Stratum typicum: Early Cenomanian
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Original description: Singh, 1983, p. 141: Spongodinium canadense
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 to 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 to 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 to 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.
Emended description Lucas- Clark, 1987, p.164:
Medium to large acavate biconical to sub-rhomboidal, gonyaulacoid cysts with thick, conical apical horn (6 to 12 µm long) capped by three or more short spines (2-5 µm long). Cingulum marked by two margins, the anterior-most a reduced ridge, without spines, showing protrusions that apparently represent junctions with parasutures between cingular paraplates; the posterior one a prominent lacy, perforate flange surmounted by a single tow of 25-35 capitate spines each about 5 µm long, more or less evenly distributed along the edge of the cingular flange. Spines on the cingular flange have anchor-shaped tips and do not seem to bear a relationship to paratabulation.
Antapex ornamented with perforate material and 10 to 15 spines along the perimeter of the antapical paraplate. The two gonal spines at the dorsal corners of the antapical paraplate sometimes more prominent than other antapical spines, but usually not more than 10 µm in length.
Outline in dorsal-ventral view more or less biconical with anterolateral angulations (shoulders) formed by the dorsal apical paraplates. Outline in lateral view biconical with concave dorsal hypocyst. Outline in apical view circular with sulcus indicated by a slight indentation or only by break in cingular flange.
Ridges of perforate, lacy ornament form parasutural markings that outline most paraplates. Low ridges, wall thickenings, or pits in the wall may partly outline some paraplates. Paraplates in the apical and antapical regions commonly covered with similar lacy ornament. Paratabulation as described for genus. Preapical paraplate P is represented by a short, solid, cylindrical "plug" at the tip of the horn between three prominent spines and occasional smaller spines. The three more prominent spines, by their relationship to parasutures, appear to be gonal spines at the junctions of 1u/A/P, A/B/P, and B/ 1 u/P. Spines present elsewhere on the cyst often seem to represent paraplate triple junctions except along the cingulum.
Remarks. The principal differences between this description and that of Singh, 1983 are (1) the recognition of paratabulation and (2) description of the ornament or wall structure as perforate and lacy, rather than "vesicular" with "alveoli."
Affinities:
Singh, 1983, p. 141: Spongodinium canadense
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.
Lucas- Clark, 1987, p165:
W. canadensis is distinguished from W. grandstandica by its thicker, shorter horn, smaller and more numerous spines, more obvious traces of paratabulation, more extensive lacy ornament, and more distinct anterior cingular margin.
Wigginsiella canadensis (Singh, 1983, p.141, pl.49, figs.1–3) Lucas-Clark, 1987, p.164. Emendation: Lucas-Clark, 1987, p.164, as Wigginsiella canadensis.
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: Upper Shaftesbury Formation of the Peace River area
Stratum typicum: Early Cenomanian
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Original description: Singh, 1983, p. 141: Spongodinium canadense
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 to 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 to 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 to 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.
Emended description Lucas- Clark, 1987, p.164:
Medium to large acavate biconical to sub-rhomboidal, gonyaulacoid cysts with thick, conical apical horn (6 to 12 µm long) capped by three or more short spines (2-5 µm long). Cingulum marked by two margins, the anterior-most a reduced ridge, without spines, showing protrusions that apparently represent junctions with parasutures between cingular paraplates; the posterior one a prominent lacy, perforate flange surmounted by a single tow of 25-35 capitate spines each about 5 µm long, more or less evenly distributed along the edge of the cingular flange. Spines on the cingular flange have anchor-shaped tips and do not seem to bear a relationship to paratabulation.
Antapex ornamented with perforate material and 10 to 15 spines along the perimeter of the antapical paraplate. The two gonal spines at the dorsal corners of the antapical paraplate sometimes more prominent than other antapical spines, but usually not more than 10 µm in length.
Outline in dorsal-ventral view more or less biconical with anterolateral angulations (shoulders) formed by the dorsal apical paraplates. Outline in lateral view biconical with concave dorsal hypocyst. Outline in apical view circular with sulcus indicated by a slight indentation or only by break in cingular flange.
Ridges of perforate, lacy ornament form parasutural markings that outline most paraplates. Low ridges, wall thickenings, or pits in the wall may partly outline some paraplates. Paraplates in the apical and antapical regions commonly covered with similar lacy ornament. Paratabulation as described for genus. Preapical paraplate P is represented by a short, solid, cylindrical "plug" at the tip of the horn between three prominent spines and occasional smaller spines. The three more prominent spines, by their relationship to parasutures, appear to be gonal spines at the junctions of 1u/A/P, A/B/P, and B/ 1 u/P. Spines present elsewhere on the cyst often seem to represent paraplate triple junctions except along the cingulum.
Remarks. The principal differences between this description and that of Singh, 1983 are (1) the recognition of paratabulation and (2) description of the ornament or wall structure as perforate and lacy, rather than "vesicular" with "alveoli."
Affinities:
Singh, 1983, p. 141: Spongodinium canadense
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.
Lucas- Clark, 1987, p165:
W. canadensis is distinguished from W. grandstandica by its thicker, shorter horn, smaller and more numerous spines, more obvious traces of paratabulation, more extensive lacy ornament, and more distinct anterior cingular margin.