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Kisselevia
From Fensome et al., 2019:
"Kisselevia", Vozzhennikova, 1963, p.183 ex Vozzhennikova, 1967, p.103.
Emendations: Lentin and Williams, 1976, p.134–137 and Lentin and Vozzhennikova, 1989, p.221, both as Kisselovia.
Taxonomic senior synonym: Rhombodinium, according to Williams et al. (2015, p.309–310). This name, as Kisselovia, was not validly published
in Vozzhennikova (1963) since no validly published species names were assigned to it: Vozzhennikova (1963) indicated a "type species (Kisselevia ornata), but did not provide a description for it, and since she assigned two species to the genus, the generic description cannot be taken as the description of the "type species" also. Williams et al. (1998, p.350) indicated that the correct spelling of this generic name is Kisselevia, as this was the version used in the validating publication (Vozzhennikova, 1967).
Type: Vozzhennikova, 1967, pl.44, fig.6, as Kisselevia ornata (which see for lectotype).
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Original description: [Vozzhennikova, 1963]:
Description:
Shells have a regular pentagonal, slightly compressed form with very short apical and two antapical horns, sometimes of different length. Both
transverse and longitudinal furrows present, the latter not always discernible. Test smooth or has reticulate pattern with spinules in modal connections, or without them. Shell cavity occupied by internal body; in the absence of the latter, its outline is still visible.
Dimension:
Length of shell with protuberance 102-160µm, width 80-135µm. Two species.
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Emended description Kisselovia:
Lentin and Williams, 1976:
Description:
Theca regularly pentagonal, strongly compressed dorso-ventrally, with a short apical and two short antapical horns. The lateral walls of the theca (in places where the epitheca and hypotheca join) have blunt, angular projections. Transverse furrow equatorial, annulate. Longitudinal furrow present on hypotheca. Theca surface reticulate or reticulate-spinose. Thecal wall subdivided into plates (fields), whose number cannot be determined. Pylome is trapezoidal to quadrangular. Internal outline of theca is clearly visible.
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Lentin and Vozzhenikova, 1989:
Diagnosis:
Dorso-ventrally compressed peridinioid cysts, roundly pentagonal without well developed horns; circumcavate; endophragm very thin, unornamented, outline of the endophragm closely following that of the periphragm. Periphragm externally ornamented by a low reticulum which may be absent over the pandasutural areas. Low porelike hollow tubes or delicate spinules may be present at the junctions of the reticulum. Reduction of the reticulum over the pandasutural regions may outline the shape of the paraplates and thus, partly or completely, may indicate the paratabulation. Formula, peridiniacean, 4`, 3a, 7", 6c, 5```, 2````. Archeopyle type 1/1, quadra, free or attached. Paracingulum indicated by a reduction or change in the reticulate network on the periphragm and by lateral indentations. Parasulcal area often distinct due to small areas of reticulum.
Affinities:
Kisselovia differs from Charlesdowniea in lacking an ectophragm and processes (see Fig.3). It differs from all other members of the Wetzeliella group in the reticulate ornament on the periphragm.
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Modified description Kisselovia:
Stover and Evitt, 1978, p. 111:
Synopsis:
Cysts proximate to proximochorate, circumcavate, compressed peridinioid, typically with one apical, two lateral, and two antapical horns, of which some may be reduced or absent; periphragm has normally tubular, occasionally solid processes arranged in intratabular clusters or penitabular rows; some or all groups of processes connected distally or covered by pieces of ectophragm; paratabulation peridiniacean, quadra style, indicated by intratabular features; archeopyle intercalary, Type l/l; archeopyle index <0.5.
Description:
Shape: Compressed peridinioid, typically with apical horns and with or without lateral horns.
Wall Relationships: Cysts circumcavate; endocyst broadly elliptical in outline and widely to narrowly separated from pericyst; ectophragm incomplete, present over some or all intratabular areas, and consistently absent over pandasuturate areas.
Wall Features: No parasutural features. Processes smooth, tubular or solid, arranged in intratabular clusters; processes may be reduced in number or lacking on midventral and middorsal surfaces. Pandasuturate areas smooth to faintly ornamented; ectophragm smooth, faintly ornamented, or reticulate.
Paratabulation: Indicated partly to completely on periphragm by intratabular and pandasuturate features, on ectophragm by the isolated
ectophragmal pieces whose outlines tend to approximate the shapes of paraplates; peridiniacean, quadra style, formula: 4`, 3a, 7", Xc or 5c, 5```, 2````, 0s or 2-4s.
Archeopyle: Intercalary, Type l/l (2a only); archeopyle index <0.5; operculum normally free.
Paracingulum: Indicated by one or more of the following: (1) transverse alignment of processes on the dorsal and ventral surfaces, (2) five rectilinear, intratabular groups of processes, (3) interruption of lateral and nearly lateral features, and (4) development of lateral horns.
Parasulcus: Not indicated, or indicated by a shallow, poorly delimited depression on the hypocyst, or by two to four intratabular clusters of processes.
Size: Intermediate to large.
Affinities:
Kisselovia differs from Wetzeliella in having all or some of the intratabular groups of processes covered by pieces of ectophragm whose outlines approximate the shapes of paraplates. In Wetzeliella, the ends of the processes are not interconnected or covered.
"Kisselevia", Vozzhennikova, 1963, p.183 ex Vozzhennikova, 1967, p.103.
Emendations: Lentin and Williams, 1976, p.134–137 and Lentin and Vozzhennikova, 1989, p.221, both as Kisselovia.
Taxonomic senior synonym: Rhombodinium, according to Williams et al. (2015, p.309–310). This name, as Kisselovia, was not validly published
in Vozzhennikova (1963) since no validly published species names were assigned to it: Vozzhennikova (1963) indicated a "type species (Kisselevia ornata), but did not provide a description for it, and since she assigned two species to the genus, the generic description cannot be taken as the description of the "type species" also. Williams et al. (1998, p.350) indicated that the correct spelling of this generic name is Kisselevia, as this was the version used in the validating publication (Vozzhennikova, 1967).
Type: Vozzhennikova, 1967, pl.44, fig.6, as Kisselevia ornata (which see for lectotype).
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Original description: [Vozzhennikova, 1963]:
Description:
Shells have a regular pentagonal, slightly compressed form with very short apical and two antapical horns, sometimes of different length. Both
transverse and longitudinal furrows present, the latter not always discernible. Test smooth or has reticulate pattern with spinules in modal connections, or without them. Shell cavity occupied by internal body; in the absence of the latter, its outline is still visible.
Dimension:
Length of shell with protuberance 102-160µm, width 80-135µm. Two species.
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Emended description Kisselovia:
Lentin and Williams, 1976:
Description:
Theca regularly pentagonal, strongly compressed dorso-ventrally, with a short apical and two short antapical horns. The lateral walls of the theca (in places where the epitheca and hypotheca join) have blunt, angular projections. Transverse furrow equatorial, annulate. Longitudinal furrow present on hypotheca. Theca surface reticulate or reticulate-spinose. Thecal wall subdivided into plates (fields), whose number cannot be determined. Pylome is trapezoidal to quadrangular. Internal outline of theca is clearly visible.
------------------------------------------------
Lentin and Vozzhenikova, 1989:
Diagnosis:
Dorso-ventrally compressed peridinioid cysts, roundly pentagonal without well developed horns; circumcavate; endophragm very thin, unornamented, outline of the endophragm closely following that of the periphragm. Periphragm externally ornamented by a low reticulum which may be absent over the pandasutural areas. Low porelike hollow tubes or delicate spinules may be present at the junctions of the reticulum. Reduction of the reticulum over the pandasutural regions may outline the shape of the paraplates and thus, partly or completely, may indicate the paratabulation. Formula, peridiniacean, 4`, 3a, 7", 6c, 5```, 2````. Archeopyle type 1/1, quadra, free or attached. Paracingulum indicated by a reduction or change in the reticulate network on the periphragm and by lateral indentations. Parasulcal area often distinct due to small areas of reticulum.
Affinities:
Kisselovia differs from Charlesdowniea in lacking an ectophragm and processes (see Fig.3). It differs from all other members of the Wetzeliella group in the reticulate ornament on the periphragm.
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Modified description Kisselovia:
Stover and Evitt, 1978, p. 111:
Synopsis:
Cysts proximate to proximochorate, circumcavate, compressed peridinioid, typically with one apical, two lateral, and two antapical horns, of which some may be reduced or absent; periphragm has normally tubular, occasionally solid processes arranged in intratabular clusters or penitabular rows; some or all groups of processes connected distally or covered by pieces of ectophragm; paratabulation peridiniacean, quadra style, indicated by intratabular features; archeopyle intercalary, Type l/l; archeopyle index <0.5.
Description:
Shape: Compressed peridinioid, typically with apical horns and with or without lateral horns.
Wall Relationships: Cysts circumcavate; endocyst broadly elliptical in outline and widely to narrowly separated from pericyst; ectophragm incomplete, present over some or all intratabular areas, and consistently absent over pandasuturate areas.
Wall Features: No parasutural features. Processes smooth, tubular or solid, arranged in intratabular clusters; processes may be reduced in number or lacking on midventral and middorsal surfaces. Pandasuturate areas smooth to faintly ornamented; ectophragm smooth, faintly ornamented, or reticulate.
Paratabulation: Indicated partly to completely on periphragm by intratabular and pandasuturate features, on ectophragm by the isolated
ectophragmal pieces whose outlines tend to approximate the shapes of paraplates; peridiniacean, quadra style, formula: 4`, 3a, 7", Xc or 5c, 5```, 2````, 0s or 2-4s.
Archeopyle: Intercalary, Type l/l (2a only); archeopyle index <0.5; operculum normally free.
Paracingulum: Indicated by one or more of the following: (1) transverse alignment of processes on the dorsal and ventral surfaces, (2) five rectilinear, intratabular groups of processes, (3) interruption of lateral and nearly lateral features, and (4) development of lateral horns.
Parasulcus: Not indicated, or indicated by a shallow, poorly delimited depression on the hypocyst, or by two to four intratabular clusters of processes.
Size: Intermediate to large.
Affinities:
Kisselovia differs from Wetzeliella in having all or some of the intratabular groups of processes covered by pieces of ectophragm whose outlines approximate the shapes of paraplates. In Wetzeliella, the ends of the processes are not interconnected or covered.